When an app has some regular pages allocated (e.g. see below) and tries
to mmap() a huge page at a hint address covered by the same PMD entry,
the kernel accepts the hint allthough the 8xx cannot handle different
page sizes in the same PMD entry.
10000000-10001000 r-xp 00000000 00:0f 2597 /root/malloc
10010000-10011000 rwxp 00000000 00:0f 2597 /root/malloc
mmap(0x10080000, 524288, PROT_READ|PROT_WRITE,
MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0) = 0x10080000
This results in the following warning, and the app remains forever in
do_page_fault()/hugetlb_fault()
[162980.035629] WARNING: CPU: 0 PID: 2777 at arch/powerpc/mm/hugetlbpage.c:354 hugetlb_free_pgd_range+0xc8/0x1e4
[162980.035699] CPU: 0 PID: 2777 Comm: malloc Tainted: G W 4.14.6 #85
[162980.035744] task: c67e2c00 task.stack: c668e000
[162980.035783] NIP: c000fe18 LR: c00e1eec CTR: c00f90c0
[162980.035830] REGS: c668fc20 TRAP: 0700 Tainted: G W (4.14.6)
[162980.035854] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 24044224 XER: 20000000
[162980.036003]
[162980.036003] GPR00: c00e1eec c668fcd0 c67e2c00 00000010 c6869410 10080000 00000000 77fb4000
[162980.036003] GPR08: ffff0001 0683c001 00000000 ffffff80 44028228 10018a34 00004008 418004fc
[162980.036003] GPR16: c668e000 00040100 c668e000 c06c0000 c668fe78 c668e000 c6835ba0 c668fd48
[162980.036003] GPR24: 00000000 73ffffff 74000000 00000001 77fb4000 100fffff 10100000 10100000
[162980.036743] NIP [c000fe18] hugetlb_free_pgd_range+0xc8/0x1e4
[162980.036839] LR [c00e1eec] free_pgtables+0x12c/0x150
[162980.036861] Call Trace:
[162980.036939] [c668fcd0] [c00f0774] unlink_anon_vmas+0x1c4/0x214 (unreliable)
[162980.037040] [c668fd10] [c00e1eec] free_pgtables+0x12c/0x150
[162980.037118] [c668fd40] [c00eabac] exit_mmap+0xe8/0x1b4
[162980.037210] [c668fda0] [c0019710] mmput.part.9+0x20/0xd8
[162980.037301] [c668fdb0] [c001ecb0] do_exit+0x1f0/0x93c
[162980.037386] [c668fe00] [c001f478] do_group_exit+0x40/0xcc
[162980.037479] [c668fe10] [c002a76c] get_signal+0x47c/0x614
[162980.037570] [c668fe70] [c0007840] do_signal+0x54/0x244
[162980.037654] [c668ff30] [c0007ae8] do_notify_resume+0x34/0x88
[162980.037744] [c668ff40] [c000dae8] do_user_signal+0x74/0xc4
[162980.037781] Instruction dump:
[162980.037821] 7fdff378 81370000 54a3463a 80890020 7d24182e 7c841a14 712a0004 4082ff94
[162980.038014] 2f890000 419e0010 712a0ff0 408200e0 <0fe00000> 54a9000a 7f984840 419d0094
[162980.038216] ---[ end trace c0ceeca8e7a5800a ]---
[162980.038754] BUG: non-zero nr_ptes on freeing mm: 1
[162985.363322] BUG: non-zero nr_ptes on freeing mm: -1
In order to fix this, the address space "slices" implemented
for BOOK3S/64 is reused.
This patch:
1/ Modifies the "slices" implementation to support 32 bits CPUs,
based on using only the low slices.
2/ Moves "slices" functions prototypes from page64.h to page.h
3/ Modifies the context.id on the 8xx to be in the range [1:16]
instead of [0:15] in order to identify context.id == 0 as
not initialised contexts
4/ Activates CONFIG_PPC_MM_SLICES when CONFIG_HUGETLB_PAGE is
selected for the 8xx
Alltough we could in theory have as many slices as PMD entries, the current
slices implementation limits the number of low slices to 16.
Fixes: 4b91428699477 ("powerpc/8xx: Implement support of hugepages")
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/mmu-8xx.h | 6 ++++
arch/powerpc/include/asm/page.h | 14 ++++++++
arch/powerpc/include/asm/page_32.h | 19 +++++++++++
arch/powerpc/include/asm/page_64.h | 21 ++----------
arch/powerpc/kernel/setup-common.c | 2 +-
arch/powerpc/mm/8xx_mmu.c | 2 +-
arch/powerpc/mm/hash_utils_64.c | 2 +-
arch/powerpc/mm/hugetlbpage.c | 2 ++
arch/powerpc/mm/mmu_context_nohash.c | 11 +++++--
arch/powerpc/mm/slice.c | 58 +++++++++++++++++++++++-----------
arch/powerpc/platforms/Kconfig.cputype | 1 +
11 files changed, 95 insertions(+), 43 deletions(-)
diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
index 5bb3dbede41a..5f89b6010453 100644
--- a/arch/powerpc/include/asm/mmu-8xx.h
+++ b/arch/powerpc/include/asm/mmu-8xx.h
@@ -169,6 +169,12 @@ typedef struct {
unsigned int id;
unsigned int active;
unsigned long vdso_base;
+#ifdef CONFIG_PPC_MM_SLICES
+ u16 user_psize; /* page size index */
+ u64 low_slices_psize; /* page size encodings */
+ unsigned char high_slices_psize[0];
+ unsigned long slb_addr_limit;
+#endif
} mm_context_t;
#define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
index 8da5d4c1cab2..d0384f9db9eb 100644
--- a/arch/powerpc/include/asm/page.h
+++ b/arch/powerpc/include/asm/page.h
@@ -342,6 +342,20 @@ typedef struct page *pgtable_t;
#endif
#endif
+#ifdef CONFIG_PPC_MM_SLICES
+struct mm_struct;
+
+unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
+ unsigned long flags, unsigned int psize,
+ int topdown);
+
+unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr);
+
+void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
+void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
+ unsigned long len, unsigned int psize);
+#endif
+
#include <asm-generic/memory_model.h>
#endif /* __ASSEMBLY__ */
diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
index 5c378e9b78c8..f7d1bd1183c8 100644
--- a/arch/powerpc/include/asm/page_32.h
+++ b/arch/powerpc/include/asm/page_32.h
@@ -60,4 +60,23 @@ extern void copy_page(void *to, void *from);
#endif /* __ASSEMBLY__ */
+#ifdef CONFIG_PPC_MM_SLICES
+
+#define SLICE_LOW_SHIFT 28
+#define SLICE_HIGH_SHIFT 0
+
+#define SLICE_LOW_TOP (0xfffffffful)
+#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
+#define SLICE_NUM_HIGH 0ul
+
+#define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
+#define GET_HIGH_SLICE_INDEX(addr) (addr & 0)
+
+#ifdef CONFIG_HUGETLB_PAGE
+#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+#endif
+#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+
+#endif
#endif /* _ASM_POWERPC_PAGE_32_H */
diff --git a/arch/powerpc/include/asm/page_64.h b/arch/powerpc/include/asm/page_64.h
index 56234c6fcd61..a7baef5bbe5f 100644
--- a/arch/powerpc/include/asm/page_64.h
+++ b/arch/powerpc/include/asm/page_64.h
@@ -91,30 +91,13 @@ extern u64 ppc64_pft_size;
#define SLICE_LOW_SHIFT 28
#define SLICE_HIGH_SHIFT 40
-#define SLICE_LOW_TOP (0x100000000ul)
-#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
+#define SLICE_LOW_TOP (0xfffffffful)
+#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
#define SLICE_NUM_HIGH (H_PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
#define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
#define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
-#ifndef __ASSEMBLY__
-struct mm_struct;
-
-extern unsigned long slice_get_unmapped_area(unsigned long addr,
- unsigned long len,
- unsigned long flags,
- unsigned int psize,
- int topdown);
-
-extern unsigned int get_slice_psize(struct mm_struct *mm,
- unsigned long addr);
-
-extern void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
-extern void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
- unsigned long len, unsigned int psize);
-
-#endif /* __ASSEMBLY__ */
#else
#define slice_init()
#ifdef CONFIG_PPC_BOOK3S_64
diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 9d213542a48b..a285e1067713 100644
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -928,7 +928,7 @@ void __init setup_arch(char **cmdline_p)
if (!radix_enabled())
init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
#else
-#error "context.addr_limit not initialized."
+ init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
#endif
#endif
diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
index f29212e40f40..0be77709446c 100644
--- a/arch/powerpc/mm/8xx_mmu.c
+++ b/arch/powerpc/mm/8xx_mmu.c
@@ -192,7 +192,7 @@ void set_context(unsigned long id, pgd_t *pgd)
mtspr(SPRN_M_TW, __pa(pgd) - offset);
/* Update context */
- mtspr(SPRN_M_CASID, id);
+ mtspr(SPRN_M_CASID, id - 1);
/* sync */
mb();
}
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 655a5a9a183d..3266b3326088 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1101,7 +1101,7 @@ static unsigned int get_paca_psize(unsigned long addr)
unsigned char *hpsizes;
unsigned long index, mask_index;
- if (addr < SLICE_LOW_TOP) {
+ if (addr <= SLICE_LOW_TOP) {
lpsizes = get_paca()->mm_ctx_low_slices_psize;
index = GET_LOW_SLICE_INDEX(addr);
return (lpsizes >> (index * 4)) & 0xF;
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index a9b9083c5e49..79e1378ee303 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -553,9 +553,11 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
struct hstate *hstate = hstate_file(file);
int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
+#ifdef CONFIG_PPC_RADIX_MMU
if (radix_enabled())
return radix__hugetlb_get_unmapped_area(file, addr, len,
pgoff, flags);
+#endif
return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1);
}
#endif
diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
index 4554d6527682..c1e1bf186871 100644
--- a/arch/powerpc/mm/mmu_context_nohash.c
+++ b/arch/powerpc/mm/mmu_context_nohash.c
@@ -331,6 +331,13 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm)
{
pr_hard("initing context for mm @%p\n", mm);
+#ifdef CONFIG_PPC_MM_SLICES
+ if (!mm->context.slb_addr_limit)
+ mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
+ if (!mm->context.id)
+ slice_set_user_psize(mm, mmu_virtual_psize);
+#endif
+
mm->context.id = MMU_NO_CONTEXT;
mm->context.active = 0;
return 0;
@@ -428,8 +435,8 @@ void __init mmu_context_init(void)
* -- BenH
*/
if (mmu_has_feature(MMU_FTR_TYPE_8xx)) {
- first_context = 0;
- last_context = 15;
+ first_context = 1;
+ last_context = 16;
no_selective_tlbil = true;
} else if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
first_context = 1;
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 23ec2c5e3b78..1a66fafc3e45 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -73,10 +73,11 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
unsigned long end = start + len - 1;
ret->low_slices = 0;
- bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
- if (start < SLICE_LOW_TOP) {
- unsigned long mend = min(end, (SLICE_LOW_TOP - 1));
+ if (start <= SLICE_LOW_TOP) {
+ unsigned long mend = min(end, SLICE_LOW_TOP);
ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
- (1u << GET_LOW_SLICE_INDEX(start));
@@ -117,7 +118,7 @@ static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
* of the high or low area bitmaps, the first high area starts
* at 4GB, not 0 */
if (start == 0)
- start = SLICE_LOW_TOP;
+ start = SLICE_LOW_TOP + 1;
return !slice_area_is_free(mm, start, end - start);
}
@@ -128,7 +129,8 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
unsigned long i;
ret->low_slices = 0;
- bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
for (i = 0; i < SLICE_NUM_LOW; i++)
if (!slice_low_has_vma(mm, i))
@@ -151,7 +153,8 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
u64 lpsizes;
ret->low_slices = 0;
- bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
lpsizes = mm->context.low_slices_psize;
for (i = 0; i < SLICE_NUM_LOW; i++)
@@ -180,15 +183,18 @@ static int slice_check_fit(struct mm_struct *mm,
*/
unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
- bitmap_and(result, mask.high_slices,
- available.high_slices, slice_count);
+ if (SLICE_NUM_HIGH)
+ bitmap_and(result, mask.high_slices,
+ available.high_slices, slice_count);
return (mask.low_slices & available.low_slices) == mask.low_slices &&
- bitmap_equal(result, mask.high_slices, slice_count);
+ (!slice_count ||
+ bitmap_equal(result, mask.high_slices, slice_count));
}
static void slice_flush_segments(void *parm)
{
+#ifdef CONFIG_PPC_BOOK3S_64
struct mm_struct *mm = parm;
unsigned long flags;
@@ -200,6 +206,7 @@ static void slice_flush_segments(void *parm)
local_irq_save(flags);
slb_flush_and_rebolt();
local_irq_restore(flags);
+#endif
}
static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
@@ -259,7 +266,7 @@ static bool slice_scan_available(unsigned long addr,
unsigned long *boundary_addr)
{
unsigned long slice;
- if (addr < SLICE_LOW_TOP) {
+ if (addr <= SLICE_LOW_TOP) {
slice = GET_LOW_SLICE_INDEX(addr);
*boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
return !!(available.low_slices & (1u << slice));
@@ -391,8 +398,11 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
DECLARE_BITMAP(result, SLICE_NUM_HIGH);
dst->low_slices |= src->low_slices;
- bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
- bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH) {
+ bitmap_or(result, dst->high_slices, src->high_slices,
+ SLICE_NUM_HIGH);
+ bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+ }
}
static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *src)
@@ -401,12 +411,17 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
dst->low_slices &= ~src->low_slices;
- bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
- bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH) {
+ bitmap_andnot(result, dst->high_slices, src->high_slices,
+ SLICE_NUM_HIGH);
+ bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
+ }
}
#ifdef CONFIG_PPC_64K_PAGES
#define MMU_PAGE_BASE MMU_PAGE_64K
+#elif defined(CONFIG_PPC_16K_PAGES)
+#define MMU_PAGE_BASE MMU_PAGE_16K
#else
#define MMU_PAGE_BASE MMU_PAGE_4K
#endif
@@ -450,14 +465,17 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
* init different masks
*/
mask.low_slices = 0;
- bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
/* silence stupid warning */;
potential_mask.low_slices = 0;
- bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
compat_mask.low_slices = 0;
- bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
+ if (SLICE_NUM_HIGH)
+ bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
/* Sanity checks */
BUG_ON(mm->task_size == 0);
@@ -595,7 +613,9 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
convert:
slice_andnot_mask(&mask, &good_mask);
slice_andnot_mask(&mask, &compat_mask);
- if (mask.low_slices || !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) {
+ if (mask.low_slices ||
+ (SLICE_NUM_HIGH &&
+ !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
slice_convert(mm, mask, psize);
if (psize > MMU_PAGE_BASE)
on_each_cpu(slice_flush_segments, mm, 1);
@@ -640,7 +660,7 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
return MMU_PAGE_4K;
#endif
}
- if (addr < SLICE_LOW_TOP) {
+ if (addr <= SLICE_LOW_TOP) {
u64 lpsizes;
lpsizes = mm->context.low_slices_psize;
index = GET_LOW_SLICE_INDEX(addr);
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index ae07470fde3c..73a7ea333e9e 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -334,6 +334,7 @@ config PPC_BOOK3E_MMU
config PPC_MM_SLICES
bool
default y if PPC_BOOK3S_64
+ default y if PPC_8xx && HUGETLB_PAGE
default n
config PPC_HAVE_PMU_SUPPORT
--
2.13.3
On the 8xx, we can have as many slices as PMD entries.
This means we could have 1024 slices in 4k size pages mode
and 64 slices in 16k size pages.
However, due to a stack overflow in slice_get_unmapped_area(),
we limit to 512 slices.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/mmu-8xx.h | 6 +++++-
arch/powerpc/include/asm/page_32.h | 3 ++-
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
index d669d0062da4..40aa7b0cd0dc 100644
--- a/arch/powerpc/include/asm/mmu-8xx.h
+++ b/arch/powerpc/include/asm/mmu-8xx.h
@@ -171,7 +171,11 @@ typedef struct {
unsigned long vdso_base;
#ifdef CONFIG_PPC_MM_SLICES
u16 user_psize; /* page size index */
- unsigned char low_slices_psize[8]; /* 16 slices */
+#if defined(CONFIG_PPC_16K_PAGES)
+ unsigned char low_slices_psize[32]; /* 64 slices */
+#else
+ unsigned char low_slices_psize[256]; /* 512 slices */
+#endif
unsigned char high_slices_psize[0];
unsigned long slb_addr_limit;
#endif
diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
index f7d1bd1183c8..43695ce7ee07 100644
--- a/arch/powerpc/include/asm/page_32.h
+++ b/arch/powerpc/include/asm/page_32.h
@@ -62,7 +62,8 @@ extern void copy_page(void *to, void *from);
#ifdef CONFIG_PPC_MM_SLICES
-#define SLICE_LOW_SHIFT 28
+/* SLICE_LOW_SHIFT >= 23 to avoid stack overflow in slice_get_unmapped_area() */
+#define SLICE_LOW_SHIFT (PMD_SHIFT > 23 ? PMD_SHIFT : 23)
#define SLICE_HIGH_SHIFT 0
#define SLICE_LOW_TOP (0xfffffffful)
--
2.13.3
While the implementation of the "slices" address space allows
a significant amount of high slices, it limits the number of
low slices to 16 due to the use of a single u64 low_slices element
in struct slice_mask.
In order to override this limitation, this patch switches the
handling of low_slices to BITMAPs as done already for high_slices.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/book3s/64/mmu.h | 2 +-
arch/powerpc/include/asm/mmu-8xx.h | 2 +-
arch/powerpc/include/asm/paca.h | 2 +-
arch/powerpc/kernel/paca.c | 3 +-
arch/powerpc/mm/hash_utils_64.c | 13 ++--
arch/powerpc/mm/slb_low.S | 8 ++-
arch/powerpc/mm/slice.c | 102 +++++++++++++++++--------------
7 files changed, 73 insertions(+), 59 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
index c9448e19847a..27e7e9732ea1 100644
--- a/arch/powerpc/include/asm/book3s/64/mmu.h
+++ b/arch/powerpc/include/asm/book3s/64/mmu.h
@@ -91,7 +91,7 @@ typedef struct {
struct npu_context *npu_context;
#ifdef CONFIG_PPC_MM_SLICES
- u64 low_slices_psize; /* SLB page size encodings */
+ unsigned char low_slices_psize[8]; /* SLB page size encodings */
unsigned char high_slices_psize[SLICE_ARRAY_SIZE];
unsigned long slb_addr_limit;
#else
diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
index 5f89b6010453..d669d0062da4 100644
--- a/arch/powerpc/include/asm/mmu-8xx.h
+++ b/arch/powerpc/include/asm/mmu-8xx.h
@@ -171,7 +171,7 @@ typedef struct {
unsigned long vdso_base;
#ifdef CONFIG_PPC_MM_SLICES
u16 user_psize; /* page size index */
- u64 low_slices_psize; /* page size encodings */
+ unsigned char low_slices_psize[8]; /* 16 slices */
unsigned char high_slices_psize[0];
unsigned long slb_addr_limit;
#endif
diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
index 3892db93b837..612017054825 100644
--- a/arch/powerpc/include/asm/paca.h
+++ b/arch/powerpc/include/asm/paca.h
@@ -141,7 +141,7 @@ struct paca_struct {
#ifdef CONFIG_PPC_BOOK3S
mm_context_id_t mm_ctx_id;
#ifdef CONFIG_PPC_MM_SLICES
- u64 mm_ctx_low_slices_psize;
+ unsigned char mm_ctx_low_slices_psize[8];
unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
unsigned long mm_ctx_slb_addr_limit;
#else
diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index d6597038931d..8e1566bf82b8 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -264,7 +264,8 @@ void copy_mm_to_paca(struct mm_struct *mm)
#ifdef CONFIG_PPC_MM_SLICES
VM_BUG_ON(!mm->context.slb_addr_limit);
get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
- get_paca()->mm_ctx_low_slices_psize = context->low_slices_psize;
+ memcpy(&get_paca()->mm_ctx_low_slices_psize,
+ &context->low_slices_psize, sizeof(context->low_slices_psize));
memcpy(&get_paca()->mm_ctx_high_slices_psize,
&context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
#else /* CONFIG_PPC_MM_SLICES */
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index 3266b3326088..2f0c6b527a83 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1097,19 +1097,18 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
#ifdef CONFIG_PPC_MM_SLICES
static unsigned int get_paca_psize(unsigned long addr)
{
- u64 lpsizes;
- unsigned char *hpsizes;
+ unsigned char *psizes;
unsigned long index, mask_index;
if (addr <= SLICE_LOW_TOP) {
- lpsizes = get_paca()->mm_ctx_low_slices_psize;
+ psizes = get_paca()->mm_ctx_low_slices_psize;
index = GET_LOW_SLICE_INDEX(addr);
- return (lpsizes >> (index * 4)) & 0xF;
+ } else {
+ psizes = get_paca()->mm_ctx_high_slices_psize;
+ index = GET_HIGH_SLICE_INDEX(addr);
}
- hpsizes = get_paca()->mm_ctx_high_slices_psize;
- index = GET_HIGH_SLICE_INDEX(addr);
mask_index = index & 0x1;
- return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xF;
+ return (psizes[index >> 1] >> (mask_index * 4)) & 0xF;
}
#else
diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
index 2cf5ef3fc50d..2c7c717fd2ea 100644
--- a/arch/powerpc/mm/slb_low.S
+++ b/arch/powerpc/mm/slb_low.S
@@ -200,10 +200,12 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT)
5:
/*
* Handle lpsizes
- * r9 is get_paca()->context.low_slices_psize, r11 is index
+ * r9 is get_paca()->context.low_slices_psize[index], r11 is mask_index
*/
- ld r9,PACALOWSLICESPSIZE(r13)
- mr r11,r10
+ srdi r11,r10,1 /* index */
+ addi r9,r11,PACALOWSLICESPSIZE
+ lbzx r9,r13,r9 /* r9 is lpsizes[r11] */
+ rldicl r11,r10,0,63 /* r11 = r10 & 0x1 */
6:
sldi r11,r11,2 /* index * 4 */
/* Extract the psize and multiply to get an array offset */
diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
index 1a66fafc3e45..e01ea72f21c6 100644
--- a/arch/powerpc/mm/slice.c
+++ b/arch/powerpc/mm/slice.c
@@ -43,7 +43,7 @@ static DEFINE_SPINLOCK(slice_convert_lock);
* in 1TB size.
*/
struct slice_mask {
- u64 low_slices;
+ DECLARE_BITMAP(low_slices, SLICE_NUM_LOW);
DECLARE_BITMAP(high_slices, SLICE_NUM_HIGH);
};
@@ -54,7 +54,8 @@ static void slice_print_mask(const char *label, struct slice_mask mask)
{
if (!_slice_debug)
return;
- pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW, &mask.low_slices);
+ pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW,
+ mask.low_slices);
pr_devel("%s high_slice: %*pbl\n", label, (int)SLICE_NUM_HIGH, mask.high_slices);
}
@@ -72,15 +73,18 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
{
unsigned long end = start + len - 1;
- ret->low_slices = 0;
+ bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
if (start <= SLICE_LOW_TOP) {
unsigned long mend = min(end, SLICE_LOW_TOP);
+ unsigned long start_index = GET_LOW_SLICE_INDEX(start);
+ unsigned long align_end = ALIGN(mend, (1UL << SLICE_LOW_SHIFT));
+ unsigned long count = GET_LOW_SLICE_INDEX(align_end) -
+ start_index;
- ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
- - (1u << GET_LOW_SLICE_INDEX(start));
+ bitmap_set(ret->low_slices, start_index, count);
}
if ((start + len) > SLICE_LOW_TOP) {
@@ -128,13 +132,13 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
{
unsigned long i;
- ret->low_slices = 0;
+ bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
for (i = 0; i < SLICE_NUM_LOW; i++)
if (!slice_low_has_vma(mm, i))
- ret->low_slices |= 1u << i;
+ __set_bit(i, ret->low_slices);
if (high_limit <= SLICE_LOW_TOP)
return;
@@ -147,19 +151,21 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret,
unsigned long high_limit)
{
- unsigned char *hpsizes;
+ unsigned char *hpsizes, *lpsizes;
int index, mask_index;
unsigned long i;
- u64 lpsizes;
- ret->low_slices = 0;
+ bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
lpsizes = mm->context.low_slices_psize;
- for (i = 0; i < SLICE_NUM_LOW; i++)
- if (((lpsizes >> (i * 4)) & 0xf) == psize)
- ret->low_slices |= 1u << i;
+ for (i = 0; i < SLICE_NUM_LOW; i++) {
+ mask_index = i & 0x1;
+ index = i >> 1;
+ if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
+ __set_bit(i, ret->low_slices);
+ }
if (high_limit <= SLICE_LOW_TOP)
return;
@@ -176,6 +182,7 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
static int slice_check_fit(struct mm_struct *mm,
struct slice_mask mask, struct slice_mask available)
{
+ DECLARE_BITMAP(result_low, SLICE_NUM_LOW);
DECLARE_BITMAP(result, SLICE_NUM_HIGH);
/*
* Make sure we just do bit compare only to the max
@@ -183,11 +190,13 @@ static int slice_check_fit(struct mm_struct *mm,
*/
unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
+ bitmap_and(result_low, mask.low_slices,
+ available.low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_and(result, mask.high_slices,
available.high_slices, slice_count);
- return (mask.low_slices & available.low_slices) == mask.low_slices &&
+ return bitmap_equal(result_low, mask.low_slices, SLICE_NUM_LOW) &&
(!slice_count ||
bitmap_equal(result, mask.high_slices, slice_count));
}
@@ -213,8 +222,7 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
{
int index, mask_index;
/* Write the new slice psize bits */
- unsigned char *hpsizes;
- u64 lpsizes;
+ unsigned char *hpsizes, *lpsizes;
unsigned long i, flags;
slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
@@ -226,13 +234,14 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
spin_lock_irqsave(&slice_convert_lock, flags);
lpsizes = mm->context.low_slices_psize;
- for (i = 0; i < SLICE_NUM_LOW; i++)
- if (mask.low_slices & (1u << i))
- lpsizes = (lpsizes & ~(0xful << (i * 4))) |
- (((unsigned long)psize) << (i * 4));
-
- /* Assign the value back */
- mm->context.low_slices_psize = lpsizes;
+ for (i = 0; i < SLICE_NUM_LOW; i++) {
+ mask_index = i & 0x1;
+ index = i >> 1;
+ if (test_bit(i, mask.low_slices))
+ lpsizes[index] = (lpsizes[index] &
+ ~(0xf << (mask_index * 4))) |
+ (((unsigned long)psize) << (mask_index * 4));
+ }
hpsizes = mm->context.high_slices_psize;
for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
@@ -269,7 +278,7 @@ static bool slice_scan_available(unsigned long addr,
if (addr <= SLICE_LOW_TOP) {
slice = GET_LOW_SLICE_INDEX(addr);
*boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
- return !!(available.low_slices & (1u << slice));
+ return !!test_bit(slice, available.low_slices);
} else {
slice = GET_HIGH_SLICE_INDEX(addr);
*boundary_addr = (slice + end) ?
@@ -397,7 +406,8 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
{
DECLARE_BITMAP(result, SLICE_NUM_HIGH);
- dst->low_slices |= src->low_slices;
+ bitmap_or(dst->low_slices, dst->low_slices, src->low_slices,
+ SLICE_NUM_LOW);
if (SLICE_NUM_HIGH) {
bitmap_or(result, dst->high_slices, src->high_slices,
SLICE_NUM_HIGH);
@@ -409,7 +419,8 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
{
DECLARE_BITMAP(result, SLICE_NUM_HIGH);
- dst->low_slices &= ~src->low_slices;
+ bitmap_andnot(dst->low_slices, dst->low_slices, src->low_slices,
+ SLICE_NUM_LOW);
if (SLICE_NUM_HIGH) {
bitmap_andnot(result, dst->high_slices, src->high_slices,
@@ -464,16 +475,16 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
/*
* init different masks
*/
- mask.low_slices = 0;
+ bitmap_zero(mask.low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
/* silence stupid warning */;
- potential_mask.low_slices = 0;
+ bitmap_zero(potential_mask.low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
- compat_mask.low_slices = 0;
+ bitmap_zero(compat_mask.low_slices, SLICE_NUM_LOW);
if (SLICE_NUM_HIGH)
bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
@@ -613,7 +624,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
convert:
slice_andnot_mask(&mask, &good_mask);
slice_andnot_mask(&mask, &compat_mask);
- if (mask.low_slices ||
+ if (!bitmap_empty(mask.low_slices, SLICE_NUM_LOW) ||
(SLICE_NUM_HIGH &&
!bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
slice_convert(mm, mask, psize);
@@ -647,7 +658,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
{
- unsigned char *hpsizes;
+ unsigned char *psizes;
int index, mask_index;
/*
@@ -661,15 +672,14 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
#endif
}
if (addr <= SLICE_LOW_TOP) {
- u64 lpsizes;
- lpsizes = mm->context.low_slices_psize;
+ psizes = mm->context.low_slices_psize;
index = GET_LOW_SLICE_INDEX(addr);
- return (lpsizes >> (index * 4)) & 0xf;
+ } else {
+ psizes = mm->context.high_slices_psize;
+ index = GET_HIGH_SLICE_INDEX(addr);
}
- hpsizes = mm->context.high_slices_psize;
- index = GET_HIGH_SLICE_INDEX(addr);
mask_index = index & 0x1;
- return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xf;
+ return (psizes[index >> 1] >> (mask_index * 4)) & 0xf;
}
EXPORT_SYMBOL_GPL(get_slice_psize);
@@ -690,8 +700,8 @@ EXPORT_SYMBOL_GPL(get_slice_psize);
void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
{
int index, mask_index;
- unsigned char *hpsizes;
- unsigned long flags, lpsizes;
+ unsigned char *hpsizes, *lpsizes;
+ unsigned long flags;
unsigned int old_psize;
int i;
@@ -709,12 +719,14 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
wmb();
lpsizes = mm->context.low_slices_psize;
- for (i = 0; i < SLICE_NUM_LOW; i++)
- if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
- lpsizes = (lpsizes & ~(0xful << (i * 4))) |
- (((unsigned long)psize) << (i * 4));
- /* Assign the value back */
- mm->context.low_slices_psize = lpsizes;
+ for (i = 0; i < SLICE_NUM_LOW; i++) {
+ mask_index = i & 0x1;
+ index = i >> 1;
+ if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize)
+ lpsizes[index] = (lpsizes[index] &
+ ~(0xf << (mask_index * 4))) |
+ (((unsigned long)psize) << (mask_index * 4));
+ }
hpsizes = mm->context.high_slices_psize;
for (i = 0; i < SLICE_NUM_HIGH; i++) {
--
2.13.3
Christophe Leroy <[email protected]> writes:
> On the 8xx, we can have as many slices as PMD entries.
> This means we could have 1024 slices in 4k size pages mode
> and 64 slices in 16k size pages.
>
> However, due to a stack overflow in slice_get_unmapped_area(),
> we limit to 512 slices.
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/include/asm/mmu-8xx.h | 6 +++++-
> arch/powerpc/include/asm/page_32.h | 3 ++-
> 2 files changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
> index d669d0062da4..40aa7b0cd0dc 100644
> --- a/arch/powerpc/include/asm/mmu-8xx.h
> +++ b/arch/powerpc/include/asm/mmu-8xx.h
> @@ -171,7 +171,11 @@ typedef struct {
> unsigned long vdso_base;
> #ifdef CONFIG_PPC_MM_SLICES
> u16 user_psize; /* page size index */
> - unsigned char low_slices_psize[8]; /* 16 slices */
> +#if defined(CONFIG_PPC_16K_PAGES)
> + unsigned char low_slices_psize[32]; /* 64 slices */
> +#else
> + unsigned char low_slices_psize[256]; /* 512 slices */
> +#endif
These #ifdef should be 8xx and then 16K.
> unsigned char high_slices_psize[0];
> unsigned long slb_addr_limit;
> #endif
> diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
> index f7d1bd1183c8..43695ce7ee07 100644
> --- a/arch/powerpc/include/asm/page_32.h
> +++ b/arch/powerpc/include/asm/page_32.h
> @@ -62,7 +62,8 @@ extern void copy_page(void *to, void *from);
>
> #ifdef CONFIG_PPC_MM_SLICES
>
> -#define SLICE_LOW_SHIFT 28
> +/* SLICE_LOW_SHIFT >= 23 to avoid stack overflow in slice_get_unmapped_area() */
> +#define SLICE_LOW_SHIFT (PMD_SHIFT > 23 ? PMD_SHIFT : 23)
> #define SLICE_HIGH_SHIFT 0
>
> #define SLICE_LOW_TOP (0xfffffffful)
> --
> 2.13.3
Christophe Leroy <[email protected]> writes:
> While the implementation of the "slices" address space allows
> a significant amount of high slices, it limits the number of
> low slices to 16 due to the use of a single u64 low_slices element
> in struct slice_mask.
It is not really slice_mask. it is mm_context_t.low_slice_psize which is
of type 64 and we need 4 bits per each slice to store the segment base
page size details. What is that you want to achieve here. For book3s,
we have 256MB segments upto 1TB and beyound that we use 1TB segments.
But for 256MB segments in the range from 4G - 1TB they all use the same
base page size because that is tracked by one slice in high slice.
Can you state the 8xx requirement here?
>
> In order to override this limitation, this patch switches the
> handling of low_slices to BITMAPs as done already for high_slices.
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/include/asm/book3s/64/mmu.h | 2 +-
> arch/powerpc/include/asm/mmu-8xx.h | 2 +-
> arch/powerpc/include/asm/paca.h | 2 +-
> arch/powerpc/kernel/paca.c | 3 +-
> arch/powerpc/mm/hash_utils_64.c | 13 ++--
> arch/powerpc/mm/slb_low.S | 8 ++-
> arch/powerpc/mm/slice.c | 102 +++++++++++++++++--------------
> 7 files changed, 73 insertions(+), 59 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
> index c9448e19847a..27e7e9732ea1 100644
> --- a/arch/powerpc/include/asm/book3s/64/mmu.h
> +++ b/arch/powerpc/include/asm/book3s/64/mmu.h
> @@ -91,7 +91,7 @@ typedef struct {
> struct npu_context *npu_context;
>
> #ifdef CONFIG_PPC_MM_SLICES
> - u64 low_slices_psize; /* SLB page size encodings */
> + unsigned char low_slices_psize[8]; /* SLB page size encodings */
> unsigned char high_slices_psize[SLICE_ARRAY_SIZE];
> unsigned long slb_addr_limit;
> #else
> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
> index 5f89b6010453..d669d0062da4 100644
> --- a/arch/powerpc/include/asm/mmu-8xx.h
> +++ b/arch/powerpc/include/asm/mmu-8xx.h
> @@ -171,7 +171,7 @@ typedef struct {
> unsigned long vdso_base;
> #ifdef CONFIG_PPC_MM_SLICES
> u16 user_psize; /* page size index */
> - u64 low_slices_psize; /* page size encodings */
> + unsigned char low_slices_psize[8]; /* 16 slices */
> unsigned char high_slices_psize[0];
> unsigned long slb_addr_limit;
> #endif
> diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
> index 3892db93b837..612017054825 100644
> --- a/arch/powerpc/include/asm/paca.h
> +++ b/arch/powerpc/include/asm/paca.h
> @@ -141,7 +141,7 @@ struct paca_struct {
> #ifdef CONFIG_PPC_BOOK3S
> mm_context_id_t mm_ctx_id;
> #ifdef CONFIG_PPC_MM_SLICES
> - u64 mm_ctx_low_slices_psize;
> + unsigned char mm_ctx_low_slices_psize[8];
> unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
> unsigned long mm_ctx_slb_addr_limit;
> #else
> diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
> index d6597038931d..8e1566bf82b8 100644
> --- a/arch/powerpc/kernel/paca.c
> +++ b/arch/powerpc/kernel/paca.c
> @@ -264,7 +264,8 @@ void copy_mm_to_paca(struct mm_struct *mm)
> #ifdef CONFIG_PPC_MM_SLICES
> VM_BUG_ON(!mm->context.slb_addr_limit);
> get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
> - get_paca()->mm_ctx_low_slices_psize = context->low_slices_psize;
> + memcpy(&get_paca()->mm_ctx_low_slices_psize,
> + &context->low_slices_psize, sizeof(context->low_slices_psize));
> memcpy(&get_paca()->mm_ctx_high_slices_psize,
> &context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
> #else /* CONFIG_PPC_MM_SLICES */
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index 3266b3326088..2f0c6b527a83 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -1097,19 +1097,18 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
> #ifdef CONFIG_PPC_MM_SLICES
> static unsigned int get_paca_psize(unsigned long addr)
> {
> - u64 lpsizes;
> - unsigned char *hpsizes;
> + unsigned char *psizes;
> unsigned long index, mask_index;
>
> if (addr <= SLICE_LOW_TOP) {
> - lpsizes = get_paca()->mm_ctx_low_slices_psize;
> + psizes = get_paca()->mm_ctx_low_slices_psize;
> index = GET_LOW_SLICE_INDEX(addr);
> - return (lpsizes >> (index * 4)) & 0xF;
> + } else {
> + psizes = get_paca()->mm_ctx_high_slices_psize;
> + index = GET_HIGH_SLICE_INDEX(addr);
> }
> - hpsizes = get_paca()->mm_ctx_high_slices_psize;
> - index = GET_HIGH_SLICE_INDEX(addr);
> mask_index = index & 0x1;
> - return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xF;
> + return (psizes[index >> 1] >> (mask_index * 4)) & 0xF;
> }
>
> #else
> diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
> index 2cf5ef3fc50d..2c7c717fd2ea 100644
> --- a/arch/powerpc/mm/slb_low.S
> +++ b/arch/powerpc/mm/slb_low.S
> @@ -200,10 +200,12 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT)
> 5:
> /*
> * Handle lpsizes
> - * r9 is get_paca()->context.low_slices_psize, r11 is index
> + * r9 is get_paca()->context.low_slices_psize[index], r11 is mask_index
> */
> - ld r9,PACALOWSLICESPSIZE(r13)
> - mr r11,r10
> + srdi r11,r10,1 /* index */
> + addi r9,r11,PACALOWSLICESPSIZE
> + lbzx r9,r13,r9 /* r9 is lpsizes[r11] */
> + rldicl r11,r10,0,63 /* r11 = r10 & 0x1 */
> 6:
> sldi r11,r11,2 /* index * 4 */
> /* Extract the psize and multiply to get an array offset */
> diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
> index 1a66fafc3e45..e01ea72f21c6 100644
> --- a/arch/powerpc/mm/slice.c
> +++ b/arch/powerpc/mm/slice.c
> @@ -43,7 +43,7 @@ static DEFINE_SPINLOCK(slice_convert_lock);
> * in 1TB size.
> */
> struct slice_mask {
> - u64 low_slices;
> + DECLARE_BITMAP(low_slices, SLICE_NUM_LOW);
> DECLARE_BITMAP(high_slices, SLICE_NUM_HIGH);
> };
>
> @@ -54,7 +54,8 @@ static void slice_print_mask(const char *label, struct slice_mask mask)
> {
> if (!_slice_debug)
> return;
> - pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW, &mask.low_slices);
> + pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW,
> + mask.low_slices);
> pr_devel("%s high_slice: %*pbl\n", label, (int)SLICE_NUM_HIGH, mask.high_slices);
> }
>
> @@ -72,15 +73,18 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
> {
> unsigned long end = start + len - 1;
>
> - ret->low_slices = 0;
> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> if (start <= SLICE_LOW_TOP) {
> unsigned long mend = min(end, SLICE_LOW_TOP);
> + unsigned long start_index = GET_LOW_SLICE_INDEX(start);
> + unsigned long align_end = ALIGN(mend, (1UL << SLICE_LOW_SHIFT));
> + unsigned long count = GET_LOW_SLICE_INDEX(align_end) -
> + start_index;
>
> - ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
> - - (1u << GET_LOW_SLICE_INDEX(start));
> + bitmap_set(ret->low_slices, start_index, count);
> }
>
> if ((start + len) > SLICE_LOW_TOP) {
> @@ -128,13 +132,13 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
> {
> unsigned long i;
>
> - ret->low_slices = 0;
> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> for (i = 0; i < SLICE_NUM_LOW; i++)
> if (!slice_low_has_vma(mm, i))
> - ret->low_slices |= 1u << i;
> + __set_bit(i, ret->low_slices);
>
> if (high_limit <= SLICE_LOW_TOP)
> return;
> @@ -147,19 +151,21 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
> static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret,
> unsigned long high_limit)
> {
> - unsigned char *hpsizes;
> + unsigned char *hpsizes, *lpsizes;
> int index, mask_index;
> unsigned long i;
> - u64 lpsizes;
>
> - ret->low_slices = 0;
> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> lpsizes = mm->context.low_slices_psize;
> - for (i = 0; i < SLICE_NUM_LOW; i++)
> - if (((lpsizes >> (i * 4)) & 0xf) == psize)
> - ret->low_slices |= 1u << i;
> + for (i = 0; i < SLICE_NUM_LOW; i++) {
> + mask_index = i & 0x1;
> + index = i >> 1;
> + if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
> + __set_bit(i, ret->low_slices);
> + }
>
> if (high_limit <= SLICE_LOW_TOP)
> return;
> @@ -176,6 +182,7 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
> static int slice_check_fit(struct mm_struct *mm,
> struct slice_mask mask, struct slice_mask available)
> {
> + DECLARE_BITMAP(result_low, SLICE_NUM_LOW);
> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
> /*
> * Make sure we just do bit compare only to the max
> @@ -183,11 +190,13 @@ static int slice_check_fit(struct mm_struct *mm,
> */
> unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
>
> + bitmap_and(result_low, mask.low_slices,
> + available.low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_and(result, mask.high_slices,
> available.high_slices, slice_count);
>
> - return (mask.low_slices & available.low_slices) == mask.low_slices &&
> + return bitmap_equal(result_low, mask.low_slices, SLICE_NUM_LOW) &&
> (!slice_count ||
> bitmap_equal(result, mask.high_slices, slice_count));
> }
> @@ -213,8 +222,7 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
> {
> int index, mask_index;
> /* Write the new slice psize bits */
> - unsigned char *hpsizes;
> - u64 lpsizes;
> + unsigned char *hpsizes, *lpsizes;
> unsigned long i, flags;
>
> slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
> @@ -226,13 +234,14 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
> spin_lock_irqsave(&slice_convert_lock, flags);
>
> lpsizes = mm->context.low_slices_psize;
> - for (i = 0; i < SLICE_NUM_LOW; i++)
> - if (mask.low_slices & (1u << i))
> - lpsizes = (lpsizes & ~(0xful << (i * 4))) |
> - (((unsigned long)psize) << (i * 4));
> -
> - /* Assign the value back */
> - mm->context.low_slices_psize = lpsizes;
> + for (i = 0; i < SLICE_NUM_LOW; i++) {
> + mask_index = i & 0x1;
> + index = i >> 1;
> + if (test_bit(i, mask.low_slices))
> + lpsizes[index] = (lpsizes[index] &
> + ~(0xf << (mask_index * 4))) |
> + (((unsigned long)psize) << (mask_index * 4));
> + }
>
> hpsizes = mm->context.high_slices_psize;
> for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
> @@ -269,7 +278,7 @@ static bool slice_scan_available(unsigned long addr,
> if (addr <= SLICE_LOW_TOP) {
> slice = GET_LOW_SLICE_INDEX(addr);
> *boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
> - return !!(available.low_slices & (1u << slice));
> + return !!test_bit(slice, available.low_slices);
> } else {
> slice = GET_HIGH_SLICE_INDEX(addr);
> *boundary_addr = (slice + end) ?
> @@ -397,7 +406,8 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
> {
> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>
> - dst->low_slices |= src->low_slices;
> + bitmap_or(dst->low_slices, dst->low_slices, src->low_slices,
> + SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH) {
> bitmap_or(result, dst->high_slices, src->high_slices,
> SLICE_NUM_HIGH);
> @@ -409,7 +419,8 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
> {
> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>
> - dst->low_slices &= ~src->low_slices;
> + bitmap_andnot(dst->low_slices, dst->low_slices, src->low_slices,
> + SLICE_NUM_LOW);
>
> if (SLICE_NUM_HIGH) {
> bitmap_andnot(result, dst->high_slices, src->high_slices,
> @@ -464,16 +475,16 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
> /*
> * init different masks
> */
> - mask.low_slices = 0;
> + bitmap_zero(mask.low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
>
> /* silence stupid warning */;
> - potential_mask.low_slices = 0;
> + bitmap_zero(potential_mask.low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
>
> - compat_mask.low_slices = 0;
> + bitmap_zero(compat_mask.low_slices, SLICE_NUM_LOW);
> if (SLICE_NUM_HIGH)
> bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
>
> @@ -613,7 +624,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
> convert:
> slice_andnot_mask(&mask, &good_mask);
> slice_andnot_mask(&mask, &compat_mask);
> - if (mask.low_slices ||
> + if (!bitmap_empty(mask.low_slices, SLICE_NUM_LOW) ||
> (SLICE_NUM_HIGH &&
> !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
> slice_convert(mm, mask, psize);
> @@ -647,7 +658,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
>
> unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
> {
> - unsigned char *hpsizes;
> + unsigned char *psizes;
> int index, mask_index;
>
> /*
> @@ -661,15 +672,14 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
> #endif
> }
> if (addr <= SLICE_LOW_TOP) {
> - u64 lpsizes;
> - lpsizes = mm->context.low_slices_psize;
> + psizes = mm->context.low_slices_psize;
> index = GET_LOW_SLICE_INDEX(addr);
> - return (lpsizes >> (index * 4)) & 0xf;
> + } else {
> + psizes = mm->context.high_slices_psize;
> + index = GET_HIGH_SLICE_INDEX(addr);
> }
> - hpsizes = mm->context.high_slices_psize;
> - index = GET_HIGH_SLICE_INDEX(addr);
> mask_index = index & 0x1;
> - return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xf;
> + return (psizes[index >> 1] >> (mask_index * 4)) & 0xf;
> }
> EXPORT_SYMBOL_GPL(get_slice_psize);
>
> @@ -690,8 +700,8 @@ EXPORT_SYMBOL_GPL(get_slice_psize);
> void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
> {
> int index, mask_index;
> - unsigned char *hpsizes;
> - unsigned long flags, lpsizes;
> + unsigned char *hpsizes, *lpsizes;
> + unsigned long flags;
> unsigned int old_psize;
> int i;
>
> @@ -709,12 +719,14 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
> wmb();
>
> lpsizes = mm->context.low_slices_psize;
> - for (i = 0; i < SLICE_NUM_LOW; i++)
> - if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
> - lpsizes = (lpsizes & ~(0xful << (i * 4))) |
> - (((unsigned long)psize) << (i * 4));
> - /* Assign the value back */
> - mm->context.low_slices_psize = lpsizes;
> + for (i = 0; i < SLICE_NUM_LOW; i++) {
> + mask_index = i & 0x1;
> + index = i >> 1;
> + if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize)
> + lpsizes[index] = (lpsizes[index] &
> + ~(0xf << (mask_index * 4))) |
> + (((unsigned long)psize) << (mask_index * 4));
> + }
>
> hpsizes = mm->context.high_slices_psize;
> for (i = 0; i < SLICE_NUM_HIGH; i++) {
> --
> 2.13.3
Christophe Leroy <[email protected]> writes:
> When an app has some regular pages allocated (e.g. see below) and tries
> to mmap() a huge page at a hint address covered by the same PMD entry,
> the kernel accepts the hint allthough the 8xx cannot handle different
> page sizes in the same PMD entry.
So that is a bug in get_unmapped_area function that you are using and
you want to fix that by using the slice code. Can you describe here what
the allocation restrictions are w.r.t 8xx? Do they have segments and
base page size like hash64?
>
> 10000000-10001000 r-xp 00000000 00:0f 2597 /root/malloc
> 10010000-10011000 rwxp 00000000 00:0f 2597 /root/malloc
>
> mmap(0x10080000, 524288, PROT_READ|PROT_WRITE,
> MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0) = 0x10080000
>
> This results in the following warning, and the app remains forever in
> do_page_fault()/hugetlb_fault()
>
> [162980.035629] WARNING: CPU: 0 PID: 2777 at arch/powerpc/mm/hugetlbpage.c:354 hugetlb_free_pgd_range+0xc8/0x1e4
> [162980.035699] CPU: 0 PID: 2777 Comm: malloc Tainted: G W 4.14.6 #85
> [162980.035744] task: c67e2c00 task.stack: c668e000
> [162980.035783] NIP: c000fe18 LR: c00e1eec CTR: c00f90c0
> [162980.035830] REGS: c668fc20 TRAP: 0700 Tainted: G W (4.14.6)
> [162980.035854] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 24044224 XER: 20000000
> [162980.036003]
> [162980.036003] GPR00: c00e1eec c668fcd0 c67e2c00 00000010 c6869410 10080000 00000000 77fb4000
> [162980.036003] GPR08: ffff0001 0683c001 00000000 ffffff80 44028228 10018a34 00004008 418004fc
> [162980.036003] GPR16: c668e000 00040100 c668e000 c06c0000 c668fe78 c668e000 c6835ba0 c668fd48
> [162980.036003] GPR24: 00000000 73ffffff 74000000 00000001 77fb4000 100fffff 10100000 10100000
> [162980.036743] NIP [c000fe18] hugetlb_free_pgd_range+0xc8/0x1e4
> [162980.036839] LR [c00e1eec] free_pgtables+0x12c/0x150
> [162980.036861] Call Trace:
> [162980.036939] [c668fcd0] [c00f0774] unlink_anon_vmas+0x1c4/0x214 (unreliable)
> [162980.037040] [c668fd10] [c00e1eec] free_pgtables+0x12c/0x150
> [162980.037118] [c668fd40] [c00eabac] exit_mmap+0xe8/0x1b4
> [162980.037210] [c668fda0] [c0019710] mmput.part.9+0x20/0xd8
> [162980.037301] [c668fdb0] [c001ecb0] do_exit+0x1f0/0x93c
> [162980.037386] [c668fe00] [c001f478] do_group_exit+0x40/0xcc
> [162980.037479] [c668fe10] [c002a76c] get_signal+0x47c/0x614
> [162980.037570] [c668fe70] [c0007840] do_signal+0x54/0x244
> [162980.037654] [c668ff30] [c0007ae8] do_notify_resume+0x34/0x88
> [162980.037744] [c668ff40] [c000dae8] do_user_signal+0x74/0xc4
> [162980.037781] Instruction dump:
> [162980.037821] 7fdff378 81370000 54a3463a 80890020 7d24182e 7c841a14 712a0004 4082ff94
> [162980.038014] 2f890000 419e0010 712a0ff0 408200e0 <0fe00000> 54a9000a 7f984840 419d0094
> [162980.038216] ---[ end trace c0ceeca8e7a5800a ]---
> [162980.038754] BUG: non-zero nr_ptes on freeing mm: 1
> [162985.363322] BUG: non-zero nr_ptes on freeing mm: -1
>
> In order to fix this, the address space "slices" implemented
> for BOOK3S/64 is reused.
>
> This patch:
> 1/ Modifies the "slices" implementation to support 32 bits CPUs,
> based on using only the low slices.
> 2/ Moves "slices" functions prototypes from page64.h to page.h
> 3/ Modifies the context.id on the 8xx to be in the range [1:16]
> instead of [0:15] in order to identify context.id == 0 as
> not initialised contexts
> 4/ Activates CONFIG_PPC_MM_SLICES when CONFIG_HUGETLB_PAGE is
> selected for the 8xx
>
> Alltough we could in theory have as many slices as PMD entries, the current
> slices implementation limits the number of low slices to 16.
Can you explain this more?
>
> Fixes: 4b91428699477 ("powerpc/8xx: Implement support of hugepages")
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/include/asm/mmu-8xx.h | 6 ++++
> arch/powerpc/include/asm/page.h | 14 ++++++++
> arch/powerpc/include/asm/page_32.h | 19 +++++++++++
> arch/powerpc/include/asm/page_64.h | 21 ++----------
> arch/powerpc/kernel/setup-common.c | 2 +-
> arch/powerpc/mm/8xx_mmu.c | 2 +-
> arch/powerpc/mm/hash_utils_64.c | 2 +-
> arch/powerpc/mm/hugetlbpage.c | 2 ++
> arch/powerpc/mm/mmu_context_nohash.c | 11 +++++--
> arch/powerpc/mm/slice.c | 58 +++++++++++++++++++++++-----------
> arch/powerpc/platforms/Kconfig.cputype | 1 +
> 11 files changed, 95 insertions(+), 43 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
> index 5bb3dbede41a..5f89b6010453 100644
> --- a/arch/powerpc/include/asm/mmu-8xx.h
> +++ b/arch/powerpc/include/asm/mmu-8xx.h
> @@ -169,6 +169,12 @@ typedef struct {
> unsigned int id;
> unsigned int active;
> unsigned long vdso_base;
> +#ifdef CONFIG_PPC_MM_SLICES
> + u16 user_psize; /* page size index */
> + u64 low_slices_psize; /* page size encodings */
> + unsigned char high_slices_psize[0];
> + unsigned long slb_addr_limit;
> +#endif
> } mm_context_t;
>
> #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
> index 8da5d4c1cab2..d0384f9db9eb 100644
> --- a/arch/powerpc/include/asm/page.h
> +++ b/arch/powerpc/include/asm/page.h
> @@ -342,6 +342,20 @@ typedef struct page *pgtable_t;
> #endif
> #endif
>
> +#ifdef CONFIG_PPC_MM_SLICES
> +struct mm_struct;
> +
> +unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
> + unsigned long flags, unsigned int psize,
> + int topdown);
> +
> +unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr);
> +
> +void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
> +void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
> + unsigned long len, unsigned int psize);
> +#endif
> +
> #include <asm-generic/memory_model.h>
> #endif /* __ASSEMBLY__ */
>
> diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
> index 5c378e9b78c8..f7d1bd1183c8 100644
> --- a/arch/powerpc/include/asm/page_32.h
> +++ b/arch/powerpc/include/asm/page_32.h
> @@ -60,4 +60,23 @@ extern void copy_page(void *to, void *from);
>
> #endif /* __ASSEMBLY__ */
>
> +#ifdef CONFIG_PPC_MM_SLICES
> +
> +#define SLICE_LOW_SHIFT 28
> +#define SLICE_HIGH_SHIFT 0
> +
> +#define SLICE_LOW_TOP (0xfffffffful)
> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
> +#define SLICE_NUM_HIGH 0ul
> +
> +#define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
> +#define GET_HIGH_SLICE_INDEX(addr) (addr & 0)
> +
> +#ifdef CONFIG_HUGETLB_PAGE
> +#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
> +#endif
> +#define HAVE_ARCH_UNMAPPED_AREA
> +#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
> +
> +#endif
> #endif /* _ASM_POWERPC_PAGE_32_H */
> diff --git a/arch/powerpc/include/asm/page_64.h b/arch/powerpc/include/asm/page_64.h
> index 56234c6fcd61..a7baef5bbe5f 100644
> --- a/arch/powerpc/include/asm/page_64.h
> +++ b/arch/powerpc/include/asm/page_64.h
> @@ -91,30 +91,13 @@ extern u64 ppc64_pft_size;
> #define SLICE_LOW_SHIFT 28
> #define SLICE_HIGH_SHIFT 40
>
> -#define SLICE_LOW_TOP (0x100000000ul)
> -#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
> +#define SLICE_LOW_TOP (0xfffffffful)
> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
> #define SLICE_NUM_HIGH (H_PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
Why are you changing this? is this a bug fix?
>
> #define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
> #define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
>
> -#ifndef __ASSEMBLY__
> -struct mm_struct;
> -
> -extern unsigned long slice_get_unmapped_area(unsigned long addr,
> - unsigned long len,
> - unsigned long flags,
> - unsigned int psize,
> - int topdown);
> -
> -extern unsigned int get_slice_psize(struct mm_struct *mm,
> - unsigned long addr);
> -
> -extern void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
> -extern void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
> - unsigned long len, unsigned int psize);
> -
> -#endif /* __ASSEMBLY__ */
> #else
> #define slice_init()
> #ifdef CONFIG_PPC_BOOK3S_64
> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
> index 9d213542a48b..a285e1067713 100644
> --- a/arch/powerpc/kernel/setup-common.c
> +++ b/arch/powerpc/kernel/setup-common.c
> @@ -928,7 +928,7 @@ void __init setup_arch(char **cmdline_p)
> if (!radix_enabled())
> init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
> #else
> -#error "context.addr_limit not initialized."
> + init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
> #endif
May be put this within #ifdef 8XX and retain the error?
> #endif
>
> diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
> index f29212e40f40..0be77709446c 100644
> --- a/arch/powerpc/mm/8xx_mmu.c
> +++ b/arch/powerpc/mm/8xx_mmu.c
> @@ -192,7 +192,7 @@ void set_context(unsigned long id, pgd_t *pgd)
> mtspr(SPRN_M_TW, __pa(pgd) - offset);
>
> /* Update context */
> - mtspr(SPRN_M_CASID, id);
> + mtspr(SPRN_M_CASID, id - 1);
> /* sync */
> mb();
> }
> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
> index 655a5a9a183d..3266b3326088 100644
> --- a/arch/powerpc/mm/hash_utils_64.c
> +++ b/arch/powerpc/mm/hash_utils_64.c
> @@ -1101,7 +1101,7 @@ static unsigned int get_paca_psize(unsigned long addr)
> unsigned char *hpsizes;
> unsigned long index, mask_index;
>
> - if (addr < SLICE_LOW_TOP) {
> + if (addr <= SLICE_LOW_TOP) {
If this is part of bug fix, please do it as part of seperate patch with details
> lpsizes = get_paca()->mm_ctx_low_slices_psize;
> index = GET_LOW_SLICE_INDEX(addr);
> return (lpsizes >> (index * 4)) & 0xF;
> diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
> index a9b9083c5e49..79e1378ee303 100644
> --- a/arch/powerpc/mm/hugetlbpage.c
> +++ b/arch/powerpc/mm/hugetlbpage.c
> @@ -553,9 +553,11 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
> struct hstate *hstate = hstate_file(file);
> int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
>
> +#ifdef CONFIG_PPC_RADIX_MMU
> if (radix_enabled())
> return radix__hugetlb_get_unmapped_area(file, addr, len,
> pgoff, flags);
> +#endif
> return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1);
> }
> #endif
> diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
> index 4554d6527682..c1e1bf186871 100644
> --- a/arch/powerpc/mm/mmu_context_nohash.c
> +++ b/arch/powerpc/mm/mmu_context_nohash.c
> @@ -331,6 +331,13 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm)
> {
> pr_hard("initing context for mm @%p\n", mm);
>
> +#ifdef CONFIG_PPC_MM_SLICES
> + if (!mm->context.slb_addr_limit)
> + mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
> + if (!mm->context.id)
> + slice_set_user_psize(mm, mmu_virtual_psize);
> +#endif
> +
> mm->context.id = MMU_NO_CONTEXT;
> mm->context.active = 0;
> return 0;
> @@ -428,8 +435,8 @@ void __init mmu_context_init(void)
> * -- BenH
> */
> if (mmu_has_feature(MMU_FTR_TYPE_8xx)) {
> - first_context = 0;
> - last_context = 15;
> + first_context = 1;
> + last_context = 16;
> no_selective_tlbil = true;
> } else if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
> first_context = 1;
> diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
> index 23ec2c5e3b78..1a66fafc3e45 100644
> --- a/arch/powerpc/mm/slice.c
> +++ b/arch/powerpc/mm/slice.c
> @@ -73,10 +73,11 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
> unsigned long end = start + len - 1;
>
> ret->low_slices = 0;
> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
So you don't want to use high slices but just low slice? If so can you
add that as a different patch which implements just that.
>
> - if (start < SLICE_LOW_TOP) {
> - unsigned long mend = min(end, (SLICE_LOW_TOP - 1));
> + if (start <= SLICE_LOW_TOP) {
> + unsigned long mend = min(end, SLICE_LOW_TOP);
>
> ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
> - (1u << GET_LOW_SLICE_INDEX(start));
> @@ -117,7 +118,7 @@ static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
> * of the high or low area bitmaps, the first high area starts
> * at 4GB, not 0 */
> if (start == 0)
> - start = SLICE_LOW_TOP;
> + start = SLICE_LOW_TOP + 1;
>
> return !slice_area_is_free(mm, start, end - start);
> }
> @@ -128,7 +129,8 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
> unsigned long i;
>
> ret->low_slices = 0;
> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> for (i = 0; i < SLICE_NUM_LOW; i++)
> if (!slice_low_has_vma(mm, i))
> @@ -151,7 +153,8 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
> u64 lpsizes;
>
> ret->low_slices = 0;
> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> lpsizes = mm->context.low_slices_psize;
> for (i = 0; i < SLICE_NUM_LOW; i++)
> @@ -180,15 +183,18 @@ static int slice_check_fit(struct mm_struct *mm,
> */
> unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
>
> - bitmap_and(result, mask.high_slices,
> - available.high_slices, slice_count);
> + if (SLICE_NUM_HIGH)
> + bitmap_and(result, mask.high_slices,
> + available.high_slices, slice_count);
>
> return (mask.low_slices & available.low_slices) == mask.low_slices &&
> - bitmap_equal(result, mask.high_slices, slice_count);
> + (!slice_count ||
> + bitmap_equal(result, mask.high_slices, slice_count));
> }
>
> static void slice_flush_segments(void *parm)
> {
> +#ifdef CONFIG_PPC_BOOK3S_64
> struct mm_struct *mm = parm;
> unsigned long flags;
>
> @@ -200,6 +206,7 @@ static void slice_flush_segments(void *parm)
> local_irq_save(flags);
> slb_flush_and_rebolt();
> local_irq_restore(flags);
> +#endif
> }
>
> static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
> @@ -259,7 +266,7 @@ static bool slice_scan_available(unsigned long addr,
> unsigned long *boundary_addr)
> {
> unsigned long slice;
> - if (addr < SLICE_LOW_TOP) {
> + if (addr <= SLICE_LOW_TOP) {
> slice = GET_LOW_SLICE_INDEX(addr);
> *boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
> return !!(available.low_slices & (1u << slice));
> @@ -391,8 +398,11 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>
> dst->low_slices |= src->low_slices;
> - bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
> - bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH) {
> + bitmap_or(result, dst->high_slices, src->high_slices,
> + SLICE_NUM_HIGH);
> + bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
> + }
> }
>
> static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *src)
> @@ -401,12 +411,17 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
>
> dst->low_slices &= ~src->low_slices;
>
> - bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
> - bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH) {
> + bitmap_andnot(result, dst->high_slices, src->high_slices,
> + SLICE_NUM_HIGH);
> + bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
> + }
> }
>
> #ifdef CONFIG_PPC_64K_PAGES
> #define MMU_PAGE_BASE MMU_PAGE_64K
> +#elif defined(CONFIG_PPC_16K_PAGES)
> +#define MMU_PAGE_BASE MMU_PAGE_16K
> #else
> #define MMU_PAGE_BASE MMU_PAGE_4K
> #endif
I am not sure we want them based on page size. The rule is we flush
segments on book3s63 if the page size is different from MMU_PAGE_BASE
> @@ -450,14 +465,17 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
> * init different masks
> */
> mask.low_slices = 0;
> - bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
>
> /* silence stupid warning */;
> potential_mask.low_slices = 0;
> - bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
>
> compat_mask.low_slices = 0;
> - bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
> + if (SLICE_NUM_HIGH)
> + bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
>
> /* Sanity checks */
> BUG_ON(mm->task_size == 0);
> @@ -595,7 +613,9 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
> convert:
> slice_andnot_mask(&mask, &good_mask);
> slice_andnot_mask(&mask, &compat_mask);
> - if (mask.low_slices || !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) {
> + if (mask.low_slices ||
> + (SLICE_NUM_HIGH &&
> + !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
> slice_convert(mm, mask, psize);
> if (psize > MMU_PAGE_BASE)
> on_each_cpu(slice_flush_segments, mm, 1);
> @@ -640,7 +660,7 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
> return MMU_PAGE_4K;
> #endif
> }
> - if (addr < SLICE_LOW_TOP) {
> + if (addr <= SLICE_LOW_TOP) {
> u64 lpsizes;
> lpsizes = mm->context.low_slices_psize;
> index = GET_LOW_SLICE_INDEX(addr);
> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
> index ae07470fde3c..73a7ea333e9e 100644
> --- a/arch/powerpc/platforms/Kconfig.cputype
> +++ b/arch/powerpc/platforms/Kconfig.cputype
> @@ -334,6 +334,7 @@ config PPC_BOOK3E_MMU
> config PPC_MM_SLICES
> bool
> default y if PPC_BOOK3S_64
> + default y if PPC_8xx && HUGETLB_PAGE
> default n
>
> config PPC_HAVE_PMU_SUPPORT
> --
> 2.13.3
Le 16/01/2018 à 16:53, Aneesh Kumar K.V a écrit :
> Christophe Leroy <[email protected]> writes:
>
>> On the 8xx, we can have as many slices as PMD entries.
>> This means we could have 1024 slices in 4k size pages mode
>> and 64 slices in 16k size pages.
>>
>> However, due to a stack overflow in slice_get_unmapped_area(),
>> we limit to 512 slices.
>>
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> arch/powerpc/include/asm/mmu-8xx.h | 6 +++++-
>> arch/powerpc/include/asm/page_32.h | 3 ++-
>> 2 files changed, 7 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
>> index d669d0062da4..40aa7b0cd0dc 100644
>> --- a/arch/powerpc/include/asm/mmu-8xx.h
>> +++ b/arch/powerpc/include/asm/mmu-8xx.h
>> @@ -171,7 +171,11 @@ typedef struct {
>> unsigned long vdso_base;
>> #ifdef CONFIG_PPC_MM_SLICES
>> u16 user_psize; /* page size index */
>> - unsigned char low_slices_psize[8]; /* 16 slices */
>> +#if defined(CONFIG_PPC_16K_PAGES)
>> + unsigned char low_slices_psize[32]; /* 64 slices */
>> +#else
>> + unsigned char low_slices_psize[256]; /* 512 slices */
>> +#endif
>
> These #ifdef should be 8xx and then 16K.
We are in file asm/mmu-8xx.h so it obviously only applies to 8xx
Christophe
>
>
>> unsigned char high_slices_psize[0];
>> unsigned long slb_addr_limit;
>> #endif
>> diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
>> index f7d1bd1183c8..43695ce7ee07 100644
>> --- a/arch/powerpc/include/asm/page_32.h
>> +++ b/arch/powerpc/include/asm/page_32.h
>> @@ -62,7 +62,8 @@ extern void copy_page(void *to, void *from);
>>
>> #ifdef CONFIG_PPC_MM_SLICES
>>
>> -#define SLICE_LOW_SHIFT 28
>> +/* SLICE_LOW_SHIFT >= 23 to avoid stack overflow in slice_get_unmapped_area() */
>> +#define SLICE_LOW_SHIFT (PMD_SHIFT > 23 ? PMD_SHIFT : 23)
>> #define SLICE_HIGH_SHIFT 0
>>
>> #define SLICE_LOW_TOP (0xfffffffful)
>> --
>> 2.13.3
Le 16/01/2018 à 16:49, Aneesh Kumar K.V a écrit :
> Christophe Leroy <[email protected]> writes:
>
>> When an app has some regular pages allocated (e.g. see below) and tries
>> to mmap() a huge page at a hint address covered by the same PMD entry,
>> the kernel accepts the hint allthough the 8xx cannot handle different
>> page sizes in the same PMD entry.
>
>
> So that is a bug in get_unmapped_area function that you are using and
> you want to fix that by using the slice code. Can you describe here what
> the allocation restrictions are w.r.t 8xx? Do they have segments and
> base page size like hash64?
I don't think it is a bug in get_unmapped_area() that is used by
default. It is that some HW do support mixing any page size in the same
page table (eg BOOK3E ?), but the 8xx doesn't.
In the 8xx, the page size is defined in the PGD entry, then all pages
defined in a given page table pointed by a PGD entry have the same size.
So it is similar to segments if you consider each PGD entry as a kind of
segment
>
>>
>> 10000000-10001000 r-xp 00000000 00:0f 2597 /root/malloc
>> 10010000-10011000 rwxp 00000000 00:0f 2597 /root/malloc
>>
>> mmap(0x10080000, 524288, PROT_READ|PROT_WRITE,
>> MAP_PRIVATE|MAP_ANONYMOUS|0x40000, -1, 0) = 0x10080000
>>
>> This results in the following warning, and the app remains forever in
>> do_page_fault()/hugetlb_fault()
>>
>> [162980.035629] WARNING: CPU: 0 PID: 2777 at arch/powerpc/mm/hugetlbpage.c:354 hugetlb_free_pgd_range+0xc8/0x1e4
>> [162980.035699] CPU: 0 PID: 2777 Comm: malloc Tainted: G W 4.14.6 #85
>> [162980.035744] task: c67e2c00 task.stack: c668e000
>> [162980.035783] NIP: c000fe18 LR: c00e1eec CTR: c00f90c0
>> [162980.035830] REGS: c668fc20 TRAP: 0700 Tainted: G W (4.14.6)
>> [162980.035854] MSR: 00029032 <EE,ME,IR,DR,RI> CR: 24044224 XER: 20000000
>> [162980.036003]
>> [162980.036003] GPR00: c00e1eec c668fcd0 c67e2c00 00000010 c6869410 10080000 00000000 77fb4000
>> [162980.036003] GPR08: ffff0001 0683c001 00000000 ffffff80 44028228 10018a34 00004008 418004fc
>> [162980.036003] GPR16: c668e000 00040100 c668e000 c06c0000 c668fe78 c668e000 c6835ba0 c668fd48
>> [162980.036003] GPR24: 00000000 73ffffff 74000000 00000001 77fb4000 100fffff 10100000 10100000
>> [162980.036743] NIP [c000fe18] hugetlb_free_pgd_range+0xc8/0x1e4
>> [162980.036839] LR [c00e1eec] free_pgtables+0x12c/0x150
>> [162980.036861] Call Trace:
>> [162980.036939] [c668fcd0] [c00f0774] unlink_anon_vmas+0x1c4/0x214 (unreliable)
>> [162980.037040] [c668fd10] [c00e1eec] free_pgtables+0x12c/0x150
>> [162980.037118] [c668fd40] [c00eabac] exit_mmap+0xe8/0x1b4
>> [162980.037210] [c668fda0] [c0019710] mmput.part.9+0x20/0xd8
>> [162980.037301] [c668fdb0] [c001ecb0] do_exit+0x1f0/0x93c
>> [162980.037386] [c668fe00] [c001f478] do_group_exit+0x40/0xcc
>> [162980.037479] [c668fe10] [c002a76c] get_signal+0x47c/0x614
>> [162980.037570] [c668fe70] [c0007840] do_signal+0x54/0x244
>> [162980.037654] [c668ff30] [c0007ae8] do_notify_resume+0x34/0x88
>> [162980.037744] [c668ff40] [c000dae8] do_user_signal+0x74/0xc4
>> [162980.037781] Instruction dump:
>> [162980.037821] 7fdff378 81370000 54a3463a 80890020 7d24182e 7c841a14 712a0004 4082ff94
>> [162980.038014] 2f890000 419e0010 712a0ff0 408200e0 <0fe00000> 54a9000a 7f984840 419d0094
>> [162980.038216] ---[ end trace c0ceeca8e7a5800a ]---
>> [162980.038754] BUG: non-zero nr_ptes on freeing mm: 1
>> [162985.363322] BUG: non-zero nr_ptes on freeing mm: -1
>>
>> In order to fix this, the address space "slices" implemented
>> for BOOK3S/64 is reused.
>>
>> This patch:
>> 1/ Modifies the "slices" implementation to support 32 bits CPUs,
>> based on using only the low slices.
>> 2/ Moves "slices" functions prototypes from page64.h to page.h
>> 3/ Modifies the context.id on the 8xx to be in the range [1:16]
>> instead of [0:15] in order to identify context.id == 0 as
>> not initialised contexts
>> 4/ Activates CONFIG_PPC_MM_SLICES when CONFIG_HUGETLB_PAGE is
>> selected for the 8xx
>>
>> Alltough we could in theory have as many slices as PMD entries, the current
>> slices implementation limits the number of low slices to 16.
>
> Can you explain this more?
As you commented in your other mail, mm_context_t.low_slice_psize which
is of type 64 and need 4 bits per each slice to store the segment base
page size details, so the maximum number of low slices is 64/4=16
>
>
>>
>> Fixes: 4b91428699477 ("powerpc/8xx: Implement support of hugepages")
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> arch/powerpc/include/asm/mmu-8xx.h | 6 ++++
>> arch/powerpc/include/asm/page.h | 14 ++++++++
>> arch/powerpc/include/asm/page_32.h | 19 +++++++++++
>> arch/powerpc/include/asm/page_64.h | 21 ++----------
>> arch/powerpc/kernel/setup-common.c | 2 +-
>> arch/powerpc/mm/8xx_mmu.c | 2 +-
>> arch/powerpc/mm/hash_utils_64.c | 2 +-
>> arch/powerpc/mm/hugetlbpage.c | 2 ++
>> arch/powerpc/mm/mmu_context_nohash.c | 11 +++++--
>> arch/powerpc/mm/slice.c | 58 +++++++++++++++++++++++-----------
>> arch/powerpc/platforms/Kconfig.cputype | 1 +
>> 11 files changed, 95 insertions(+), 43 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
>> index 5bb3dbede41a..5f89b6010453 100644
>> --- a/arch/powerpc/include/asm/mmu-8xx.h
>> +++ b/arch/powerpc/include/asm/mmu-8xx.h
>> @@ -169,6 +169,12 @@ typedef struct {
>> unsigned int id;
>> unsigned int active;
>> unsigned long vdso_base;
>> +#ifdef CONFIG_PPC_MM_SLICES
>> + u16 user_psize; /* page size index */
>> + u64 low_slices_psize; /* page size encodings */
>> + unsigned char high_slices_psize[0];
>> + unsigned long slb_addr_limit;
>> +#endif
>> } mm_context_t;
>>
>> #define PHYS_IMMR_BASE (mfspr(SPRN_IMMR) & 0xfff80000)
>> diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h
>> index 8da5d4c1cab2..d0384f9db9eb 100644
>> --- a/arch/powerpc/include/asm/page.h
>> +++ b/arch/powerpc/include/asm/page.h
>> @@ -342,6 +342,20 @@ typedef struct page *pgtable_t;
>> #endif
>> #endif
>>
>> +#ifdef CONFIG_PPC_MM_SLICES
>> +struct mm_struct;
>> +
>> +unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
>> + unsigned long flags, unsigned int psize,
>> + int topdown);
>> +
>> +unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr);
>> +
>> +void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
>> +void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
>> + unsigned long len, unsigned int psize);
>> +#endif
>> +
>> #include <asm-generic/memory_model.h>
>> #endif /* __ASSEMBLY__ */
>>
>> diff --git a/arch/powerpc/include/asm/page_32.h b/arch/powerpc/include/asm/page_32.h
>> index 5c378e9b78c8..f7d1bd1183c8 100644
>> --- a/arch/powerpc/include/asm/page_32.h
>> +++ b/arch/powerpc/include/asm/page_32.h
>> @@ -60,4 +60,23 @@ extern void copy_page(void *to, void *from);
>>
>> #endif /* __ASSEMBLY__ */
>>
>> +#ifdef CONFIG_PPC_MM_SLICES
>> +
>> +#define SLICE_LOW_SHIFT 28
>> +#define SLICE_HIGH_SHIFT 0
>> +
>> +#define SLICE_LOW_TOP (0xfffffffful)
>> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
>> +#define SLICE_NUM_HIGH 0ul
>> +
>> +#define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
>> +#define GET_HIGH_SLICE_INDEX(addr) (addr & 0)
>> +
>> +#ifdef CONFIG_HUGETLB_PAGE
>> +#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
>> +#endif
>> +#define HAVE_ARCH_UNMAPPED_AREA
>> +#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
>> +
>> +#endif
>> #endif /* _ASM_POWERPC_PAGE_32_H */
>> diff --git a/arch/powerpc/include/asm/page_64.h b/arch/powerpc/include/asm/page_64.h
>> index 56234c6fcd61..a7baef5bbe5f 100644
>> --- a/arch/powerpc/include/asm/page_64.h
>> +++ b/arch/powerpc/include/asm/page_64.h
>> @@ -91,30 +91,13 @@ extern u64 ppc64_pft_size;
>> #define SLICE_LOW_SHIFT 28
>> #define SLICE_HIGH_SHIFT 40
>>
>> -#define SLICE_LOW_TOP (0x100000000ul)
>> -#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
>> +#define SLICE_LOW_TOP (0xfffffffful)
>> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
>> #define SLICE_NUM_HIGH (H_PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
>
>
> Why are you changing this? is this a bug fix?
That's because 0x100000000ul is out of range of unsigned long on PPC32.
>
>>
>> #define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
>> #define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
>>
>> -#ifndef __ASSEMBLY__
>> -struct mm_struct;
>> -
>> -extern unsigned long slice_get_unmapped_area(unsigned long addr,
>> - unsigned long len,
>> - unsigned long flags,
>> - unsigned int psize,
>> - int topdown);
>> -
>> -extern unsigned int get_slice_psize(struct mm_struct *mm,
>> - unsigned long addr);
>> -
>> -extern void slice_set_user_psize(struct mm_struct *mm, unsigned int psize);
>> -extern void slice_set_range_psize(struct mm_struct *mm, unsigned long start,
>> - unsigned long len, unsigned int psize);
>> -
>> -#endif /* __ASSEMBLY__ */
>> #else
>> #define slice_init()
>> #ifdef CONFIG_PPC_BOOK3S_64
>> diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
>> index 9d213542a48b..a285e1067713 100644
>> --- a/arch/powerpc/kernel/setup-common.c
>> +++ b/arch/powerpc/kernel/setup-common.c
>> @@ -928,7 +928,7 @@ void __init setup_arch(char **cmdline_p)
>> if (!radix_enabled())
>> init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
>> #else
>> -#error "context.addr_limit not initialized."
>> + init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
>> #endif
>
>
> May be put this within #ifdef 8XX and retain the error?
Is this error really worth it ?
I wanted to avoid spreading too many #ifdef PPC_8xx, but ok I can do that.
>
>> #endif
>>
>> diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
>> index f29212e40f40..0be77709446c 100644
>> --- a/arch/powerpc/mm/8xx_mmu.c
>> +++ b/arch/powerpc/mm/8xx_mmu.c
>> @@ -192,7 +192,7 @@ void set_context(unsigned long id, pgd_t *pgd)
>> mtspr(SPRN_M_TW, __pa(pgd) - offset);
>>
>> /* Update context */
>> - mtspr(SPRN_M_CASID, id);
>> + mtspr(SPRN_M_CASID, id - 1);
>> /* sync */
>> mb();
>> }
>> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
>> index 655a5a9a183d..3266b3326088 100644
>> --- a/arch/powerpc/mm/hash_utils_64.c
>> +++ b/arch/powerpc/mm/hash_utils_64.c
>> @@ -1101,7 +1101,7 @@ static unsigned int get_paca_psize(unsigned long addr)
>> unsigned char *hpsizes;
>> unsigned long index, mask_index;
>>
>> - if (addr < SLICE_LOW_TOP) {
>> + if (addr <= SLICE_LOW_TOP) {
>
> If this is part of bug fix, please do it as part of seperate patch with details
As explained above, in order to allow comparison to work on PPC32,
SLICE_LOW_TOP has to be 0xffffffff instead of 0x100000000
How should I split in separate patches ? Something like ?
1/ Slice support for PPC32
2/ Activate slice for 8xx
>
>
>> lpsizes = get_paca()->mm_ctx_low_slices_psize;
>> index = GET_LOW_SLICE_INDEX(addr);
>> return (lpsizes >> (index * 4)) & 0xF;
>> diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
>> index a9b9083c5e49..79e1378ee303 100644
>> --- a/arch/powerpc/mm/hugetlbpage.c
>> +++ b/arch/powerpc/mm/hugetlbpage.c
>> @@ -553,9 +553,11 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
>> struct hstate *hstate = hstate_file(file);
>> int mmu_psize = shift_to_mmu_psize(huge_page_shift(hstate));
>>
>> +#ifdef CONFIG_PPC_RADIX_MMU
>> if (radix_enabled())
>> return radix__hugetlb_get_unmapped_area(file, addr, len,
>> pgoff, flags);
>> +#endif
>> return slice_get_unmapped_area(addr, len, flags, mmu_psize, 1);
>> }
>> #endif
>> diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c
>> index 4554d6527682..c1e1bf186871 100644
>> --- a/arch/powerpc/mm/mmu_context_nohash.c
>> +++ b/arch/powerpc/mm/mmu_context_nohash.c
>> @@ -331,6 +331,13 @@ int init_new_context(struct task_struct *t, struct mm_struct *mm)
>> {
>> pr_hard("initing context for mm @%p\n", mm);
>>
>> +#ifdef CONFIG_PPC_MM_SLICES
>> + if (!mm->context.slb_addr_limit)
>> + mm->context.slb_addr_limit = DEFAULT_MAP_WINDOW;
>> + if (!mm->context.id)
>> + slice_set_user_psize(mm, mmu_virtual_psize);
>> +#endif
>> +
>> mm->context.id = MMU_NO_CONTEXT;
>> mm->context.active = 0;
>> return 0;
>> @@ -428,8 +435,8 @@ void __init mmu_context_init(void)
>> * -- BenH
>> */
>> if (mmu_has_feature(MMU_FTR_TYPE_8xx)) {
>> - first_context = 0;
>> - last_context = 15;
>> + first_context = 1;
>> + last_context = 16;
>> no_selective_tlbil = true;
>> } else if (mmu_has_feature(MMU_FTR_TYPE_47x)) {
>> first_context = 1;
>> diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
>> index 23ec2c5e3b78..1a66fafc3e45 100644
>> --- a/arch/powerpc/mm/slice.c
>> +++ b/arch/powerpc/mm/slice.c
>> @@ -73,10 +73,11 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
>> unsigned long end = start + len - 1;
>>
>> ret->low_slices = 0;
>> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>
> So you don't want to use high slices but just low slice? If so can you
> add that as a different patch which implements just that.
high slices are over 0xffffffff, so pointless on PPC32.
>
>
>>
>> - if (start < SLICE_LOW_TOP) {
>> - unsigned long mend = min(end, (SLICE_LOW_TOP - 1));
>> + if (start <= SLICE_LOW_TOP) {
>> + unsigned long mend = min(end, SLICE_LOW_TOP);
>>
>> ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
>> - (1u << GET_LOW_SLICE_INDEX(start));
>> @@ -117,7 +118,7 @@ static int slice_high_has_vma(struct mm_struct *mm, unsigned long slice)
>> * of the high or low area bitmaps, the first high area starts
>> * at 4GB, not 0 */
>> if (start == 0)
>> - start = SLICE_LOW_TOP;
>> + start = SLICE_LOW_TOP + 1;
>>
>> return !slice_area_is_free(mm, start, end - start);
>> }
>> @@ -128,7 +129,8 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
>> unsigned long i;
>>
>> ret->low_slices = 0;
>> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>>
>> for (i = 0; i < SLICE_NUM_LOW; i++)
>> if (!slice_low_has_vma(mm, i))
>> @@ -151,7 +153,8 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
>> u64 lpsizes;
>>
>> ret->low_slices = 0;
>> - bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>>
>> lpsizes = mm->context.low_slices_psize;
>> for (i = 0; i < SLICE_NUM_LOW; i++)
>> @@ -180,15 +183,18 @@ static int slice_check_fit(struct mm_struct *mm,
>> */
>> unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
>>
>> - bitmap_and(result, mask.high_slices,
>> - available.high_slices, slice_count);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_and(result, mask.high_slices,
>> + available.high_slices, slice_count);
>>
>> return (mask.low_slices & available.low_slices) == mask.low_slices &&
>> - bitmap_equal(result, mask.high_slices, slice_count);
>> + (!slice_count ||
>> + bitmap_equal(result, mask.high_slices, slice_count));
>> }
>>
>> static void slice_flush_segments(void *parm)
>> {
>> +#ifdef CONFIG_PPC_BOOK3S_64
>> struct mm_struct *mm = parm;
>> unsigned long flags;
>>
>> @@ -200,6 +206,7 @@ static void slice_flush_segments(void *parm)
>> local_irq_save(flags);
>> slb_flush_and_rebolt();
>> local_irq_restore(flags);
>> +#endif
>> }
>>
>> static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psize)
>> @@ -259,7 +266,7 @@ static bool slice_scan_available(unsigned long addr,
>> unsigned long *boundary_addr)
>> {
>> unsigned long slice;
>> - if (addr < SLICE_LOW_TOP) {
>> + if (addr <= SLICE_LOW_TOP) {
>> slice = GET_LOW_SLICE_INDEX(addr);
>> *boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
>> return !!(available.low_slices & (1u << slice));
>> @@ -391,8 +398,11 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
>> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>>
>> dst->low_slices |= src->low_slices;
>> - bitmap_or(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
>> - bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH) {
>> + bitmap_or(result, dst->high_slices, src->high_slices,
>> + SLICE_NUM_HIGH);
>> + bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
>> + }
>> }
>>
>> static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *src)
>> @@ -401,12 +411,17 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
>>
>> dst->low_slices &= ~src->low_slices;
>>
>> - bitmap_andnot(result, dst->high_slices, src->high_slices, SLICE_NUM_HIGH);
>> - bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH) {
>> + bitmap_andnot(result, dst->high_slices, src->high_slices,
>> + SLICE_NUM_HIGH);
>> + bitmap_copy(dst->high_slices, result, SLICE_NUM_HIGH);
>> + }
>> }
>>
>> #ifdef CONFIG_PPC_64K_PAGES
>> #define MMU_PAGE_BASE MMU_PAGE_64K
>> +#elif defined(CONFIG_PPC_16K_PAGES)
>> +#define MMU_PAGE_BASE MMU_PAGE_16K
>> #else
>> #define MMU_PAGE_BASE MMU_PAGE_4K
>> #endif
>
> I am not sure we want them based on page size. The rule is we flush
> segments on book3s63 if the page size is different from MMU_PAGE_BASE
Do you mean this definition is just useless for the 8xx as it doesn't
have real segments ?
>
>
>> @@ -450,14 +465,17 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
>> * init different masks
>> */
>> mask.low_slices = 0;
>> - bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
>>
>> /* silence stupid warning */;
>> potential_mask.low_slices = 0;
>> - bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
>>
>> compat_mask.low_slices = 0;
>> - bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
>> + if (SLICE_NUM_HIGH)
>> + bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
>>
>> /* Sanity checks */
>> BUG_ON(mm->task_size == 0);
>> @@ -595,7 +613,9 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
>> convert:
>> slice_andnot_mask(&mask, &good_mask);
>> slice_andnot_mask(&mask, &compat_mask);
>> - if (mask.low_slices || !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH)) {
>> + if (mask.low_slices ||
>> + (SLICE_NUM_HIGH &&
>> + !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
>> slice_convert(mm, mask, psize);
>> if (psize > MMU_PAGE_BASE)
>> on_each_cpu(slice_flush_segments, mm, 1);
>> @@ -640,7 +660,7 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
>> return MMU_PAGE_4K;
>> #endif
>> }
>> - if (addr < SLICE_LOW_TOP) {
>> + if (addr <= SLICE_LOW_TOP) {
>> u64 lpsizes;
>> lpsizes = mm->context.low_slices_psize;
>> index = GET_LOW_SLICE_INDEX(addr);
>> diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
>> index ae07470fde3c..73a7ea333e9e 100644
>> --- a/arch/powerpc/platforms/Kconfig.cputype
>> +++ b/arch/powerpc/platforms/Kconfig.cputype
>> @@ -334,6 +334,7 @@ config PPC_BOOK3E_MMU
>> config PPC_MM_SLICES
>> bool
>> default y if PPC_BOOK3S_64
>> + default y if PPC_8xx && HUGETLB_PAGE
>> default n
>>
>> config PPC_HAVE_PMU_SUPPORT
>> --
>> 2.13.3
Le 16/01/2018 à 16:52, Aneesh Kumar K.V a écrit :
> Christophe Leroy <[email protected]> writes:
>
>> While the implementation of the "slices" address space allows
>> a significant amount of high slices, it limits the number of
>> low slices to 16 due to the use of a single u64 low_slices element
>> in struct slice_mask.
>
> It is not really slice_mask. it is mm_context_t.low_slice_psize which is
> of type 64 and we need 4 bits per each slice to store the segment base
> page size details. What is that you want to achieve here. For book3s,
> we have 256MB segments upto 1TB and beyound that we use 1TB segments.
> But for 256MB segments in the range from 4G - 1TB they all use the same
> base page size because that is tracked by one slice in high slice.
>
> Can you state the 8xx requirement here?
On the 8xx, we need each slice to be one or a multiple of PGD entries.
In 4k page size mode, each PGD entry covers 4M. So it may be interesting
to have slices of size 4M.
In 16k page size mode, each PGD entry covers 64M, So it may be
interesting to have slices of size 64M.
>
>
>>
>> In order to override this limitation, this patch switches the
>> handling of low_slices to BITMAPs as done already for high_slices.
>>
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> arch/powerpc/include/asm/book3s/64/mmu.h | 2 +-
>> arch/powerpc/include/asm/mmu-8xx.h | 2 +-
>> arch/powerpc/include/asm/paca.h | 2 +-
>> arch/powerpc/kernel/paca.c | 3 +-
>> arch/powerpc/mm/hash_utils_64.c | 13 ++--
>> arch/powerpc/mm/slb_low.S | 8 ++-
>> arch/powerpc/mm/slice.c | 102 +++++++++++++++++--------------
>> 7 files changed, 73 insertions(+), 59 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h
>> index c9448e19847a..27e7e9732ea1 100644
>> --- a/arch/powerpc/include/asm/book3s/64/mmu.h
>> +++ b/arch/powerpc/include/asm/book3s/64/mmu.h
>> @@ -91,7 +91,7 @@ typedef struct {
>> struct npu_context *npu_context;
>>
>> #ifdef CONFIG_PPC_MM_SLICES
>> - u64 low_slices_psize; /* SLB page size encodings */
>> + unsigned char low_slices_psize[8]; /* SLB page size encodings */
>> unsigned char high_slices_psize[SLICE_ARRAY_SIZE];
>> unsigned long slb_addr_limit;
>> #else
>> diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
>> index 5f89b6010453..d669d0062da4 100644
>> --- a/arch/powerpc/include/asm/mmu-8xx.h
>> +++ b/arch/powerpc/include/asm/mmu-8xx.h
>> @@ -171,7 +171,7 @@ typedef struct {
>> unsigned long vdso_base;
>> #ifdef CONFIG_PPC_MM_SLICES
>> u16 user_psize; /* page size index */
>> - u64 low_slices_psize; /* page size encodings */
>> + unsigned char low_slices_psize[8]; /* 16 slices */
>> unsigned char high_slices_psize[0];
>> unsigned long slb_addr_limit;
>> #endif
>> diff --git a/arch/powerpc/include/asm/paca.h b/arch/powerpc/include/asm/paca.h
>> index 3892db93b837..612017054825 100644
>> --- a/arch/powerpc/include/asm/paca.h
>> +++ b/arch/powerpc/include/asm/paca.h
>> @@ -141,7 +141,7 @@ struct paca_struct {
>> #ifdef CONFIG_PPC_BOOK3S
>> mm_context_id_t mm_ctx_id;
>> #ifdef CONFIG_PPC_MM_SLICES
>> - u64 mm_ctx_low_slices_psize;
>> + unsigned char mm_ctx_low_slices_psize[8];
>> unsigned char mm_ctx_high_slices_psize[SLICE_ARRAY_SIZE];
>> unsigned long mm_ctx_slb_addr_limit;
>> #else
>> diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
>> index d6597038931d..8e1566bf82b8 100644
>> --- a/arch/powerpc/kernel/paca.c
>> +++ b/arch/powerpc/kernel/paca.c
>> @@ -264,7 +264,8 @@ void copy_mm_to_paca(struct mm_struct *mm)
>> #ifdef CONFIG_PPC_MM_SLICES
>> VM_BUG_ON(!mm->context.slb_addr_limit);
>> get_paca()->mm_ctx_slb_addr_limit = mm->context.slb_addr_limit;
>> - get_paca()->mm_ctx_low_slices_psize = context->low_slices_psize;
>> + memcpy(&get_paca()->mm_ctx_low_slices_psize,
>> + &context->low_slices_psize, sizeof(context->low_slices_psize));
>> memcpy(&get_paca()->mm_ctx_high_slices_psize,
>> &context->high_slices_psize, TASK_SLICE_ARRAY_SZ(mm));
>> #else /* CONFIG_PPC_MM_SLICES */
>> diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
>> index 3266b3326088..2f0c6b527a83 100644
>> --- a/arch/powerpc/mm/hash_utils_64.c
>> +++ b/arch/powerpc/mm/hash_utils_64.c
>> @@ -1097,19 +1097,18 @@ unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap)
>> #ifdef CONFIG_PPC_MM_SLICES
>> static unsigned int get_paca_psize(unsigned long addr)
>> {
>> - u64 lpsizes;
>> - unsigned char *hpsizes;
>> + unsigned char *psizes;
>> unsigned long index, mask_index;
>>
>> if (addr <= SLICE_LOW_TOP) {
>> - lpsizes = get_paca()->mm_ctx_low_slices_psize;
>> + psizes = get_paca()->mm_ctx_low_slices_psize;
>> index = GET_LOW_SLICE_INDEX(addr);
>> - return (lpsizes >> (index * 4)) & 0xF;
>> + } else {
>> + psizes = get_paca()->mm_ctx_high_slices_psize;
>> + index = GET_HIGH_SLICE_INDEX(addr);
>> }
>> - hpsizes = get_paca()->mm_ctx_high_slices_psize;
>> - index = GET_HIGH_SLICE_INDEX(addr);
>> mask_index = index & 0x1;
>> - return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xF;
>> + return (psizes[index >> 1] >> (mask_index * 4)) & 0xF;
>> }
>>
>> #else
>> diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
>> index 2cf5ef3fc50d..2c7c717fd2ea 100644
>> --- a/arch/powerpc/mm/slb_low.S
>> +++ b/arch/powerpc/mm/slb_low.S
>> @@ -200,10 +200,12 @@ END_MMU_FTR_SECTION_IFCLR(MMU_FTR_1T_SEGMENT)
>> 5:
>> /*
>> * Handle lpsizes
>> - * r9 is get_paca()->context.low_slices_psize, r11 is index
>> + * r9 is get_paca()->context.low_slices_psize[index], r11 is mask_index
>> */
>> - ld r9,PACALOWSLICESPSIZE(r13)
>> - mr r11,r10
>> + srdi r11,r10,1 /* index */
>> + addi r9,r11,PACALOWSLICESPSIZE
>> + lbzx r9,r13,r9 /* r9 is lpsizes[r11] */
>> + rldicl r11,r10,0,63 /* r11 = r10 & 0x1 */
>> 6:
>> sldi r11,r11,2 /* index * 4 */
>> /* Extract the psize and multiply to get an array offset */
>> diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c
>> index 1a66fafc3e45..e01ea72f21c6 100644
>> --- a/arch/powerpc/mm/slice.c
>> +++ b/arch/powerpc/mm/slice.c
>> @@ -43,7 +43,7 @@ static DEFINE_SPINLOCK(slice_convert_lock);
>> * in 1TB size.
>> */
>> struct slice_mask {
>> - u64 low_slices;
>> + DECLARE_BITMAP(low_slices, SLICE_NUM_LOW);
>> DECLARE_BITMAP(high_slices, SLICE_NUM_HIGH);
>> };
>>
>> @@ -54,7 +54,8 @@ static void slice_print_mask(const char *label, struct slice_mask mask)
>> {
>> if (!_slice_debug)
>> return;
>> - pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW, &mask.low_slices);
>> + pr_devel("%s low_slice: %*pbl\n", label, (int)SLICE_NUM_LOW,
>> + mask.low_slices);
>> pr_devel("%s high_slice: %*pbl\n", label, (int)SLICE_NUM_HIGH, mask.high_slices);
>> }
>>
>> @@ -72,15 +73,18 @@ static void slice_range_to_mask(unsigned long start, unsigned long len,
>> {
>> unsigned long end = start + len - 1;
>>
>> - ret->low_slices = 0;
>> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>>
>> if (start <= SLICE_LOW_TOP) {
>> unsigned long mend = min(end, SLICE_LOW_TOP);
>> + unsigned long start_index = GET_LOW_SLICE_INDEX(start);
>> + unsigned long align_end = ALIGN(mend, (1UL << SLICE_LOW_SHIFT));
>> + unsigned long count = GET_LOW_SLICE_INDEX(align_end) -
>> + start_index;
>>
>> - ret->low_slices = (1u << (GET_LOW_SLICE_INDEX(mend) + 1))
>> - - (1u << GET_LOW_SLICE_INDEX(start));
>> + bitmap_set(ret->low_slices, start_index, count);
>> }
>>
>> if ((start + len) > SLICE_LOW_TOP) {
>> @@ -128,13 +132,13 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
>> {
>> unsigned long i;
>>
>> - ret->low_slices = 0;
>> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>>
>> for (i = 0; i < SLICE_NUM_LOW; i++)
>> if (!slice_low_has_vma(mm, i))
>> - ret->low_slices |= 1u << i;
>> + __set_bit(i, ret->low_slices);
>>
>> if (high_limit <= SLICE_LOW_TOP)
>> return;
>> @@ -147,19 +151,21 @@ static void slice_mask_for_free(struct mm_struct *mm, struct slice_mask *ret,
>> static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_mask *ret,
>> unsigned long high_limit)
>> {
>> - unsigned char *hpsizes;
>> + unsigned char *hpsizes, *lpsizes;
>> int index, mask_index;
>> unsigned long i;
>> - u64 lpsizes;
>>
>> - ret->low_slices = 0;
>> + bitmap_zero(ret->low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(ret->high_slices, SLICE_NUM_HIGH);
>>
>> lpsizes = mm->context.low_slices_psize;
>> - for (i = 0; i < SLICE_NUM_LOW; i++)
>> - if (((lpsizes >> (i * 4)) & 0xf) == psize)
>> - ret->low_slices |= 1u << i;
>> + for (i = 0; i < SLICE_NUM_LOW; i++) {
>> + mask_index = i & 0x1;
>> + index = i >> 1;
>> + if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == psize)
>> + __set_bit(i, ret->low_slices);
>> + }
>>
>> if (high_limit <= SLICE_LOW_TOP)
>> return;
>> @@ -176,6 +182,7 @@ static void slice_mask_for_size(struct mm_struct *mm, int psize, struct slice_ma
>> static int slice_check_fit(struct mm_struct *mm,
>> struct slice_mask mask, struct slice_mask available)
>> {
>> + DECLARE_BITMAP(result_low, SLICE_NUM_LOW);
>> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>> /*
>> * Make sure we just do bit compare only to the max
>> @@ -183,11 +190,13 @@ static int slice_check_fit(struct mm_struct *mm,
>> */
>> unsigned long slice_count = GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit);
>>
>> + bitmap_and(result_low, mask.low_slices,
>> + available.low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_and(result, mask.high_slices,
>> available.high_slices, slice_count);
>>
>> - return (mask.low_slices & available.low_slices) == mask.low_slices &&
>> + return bitmap_equal(result_low, mask.low_slices, SLICE_NUM_LOW) &&
>> (!slice_count ||
>> bitmap_equal(result, mask.high_slices, slice_count));
>> }
>> @@ -213,8 +222,7 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
>> {
>> int index, mask_index;
>> /* Write the new slice psize bits */
>> - unsigned char *hpsizes;
>> - u64 lpsizes;
>> + unsigned char *hpsizes, *lpsizes;
>> unsigned long i, flags;
>>
>> slice_dbg("slice_convert(mm=%p, psize=%d)\n", mm, psize);
>> @@ -226,13 +234,14 @@ static void slice_convert(struct mm_struct *mm, struct slice_mask mask, int psiz
>> spin_lock_irqsave(&slice_convert_lock, flags);
>>
>> lpsizes = mm->context.low_slices_psize;
>> - for (i = 0; i < SLICE_NUM_LOW; i++)
>> - if (mask.low_slices & (1u << i))
>> - lpsizes = (lpsizes & ~(0xful << (i * 4))) |
>> - (((unsigned long)psize) << (i * 4));
>> -
>> - /* Assign the value back */
>> - mm->context.low_slices_psize = lpsizes;
>> + for (i = 0; i < SLICE_NUM_LOW; i++) {
>> + mask_index = i & 0x1;
>> + index = i >> 1;
>> + if (test_bit(i, mask.low_slices))
>> + lpsizes[index] = (lpsizes[index] &
>> + ~(0xf << (mask_index * 4))) |
>> + (((unsigned long)psize) << (mask_index * 4));
>> + }
>>
>> hpsizes = mm->context.high_slices_psize;
>> for (i = 0; i < GET_HIGH_SLICE_INDEX(mm->context.slb_addr_limit); i++) {
>> @@ -269,7 +278,7 @@ static bool slice_scan_available(unsigned long addr,
>> if (addr <= SLICE_LOW_TOP) {
>> slice = GET_LOW_SLICE_INDEX(addr);
>> *boundary_addr = (slice + end) << SLICE_LOW_SHIFT;
>> - return !!(available.low_slices & (1u << slice));
>> + return !!test_bit(slice, available.low_slices);
>> } else {
>> slice = GET_HIGH_SLICE_INDEX(addr);
>> *boundary_addr = (slice + end) ?
>> @@ -397,7 +406,8 @@ static inline void slice_or_mask(struct slice_mask *dst, struct slice_mask *src)
>> {
>> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>>
>> - dst->low_slices |= src->low_slices;
>> + bitmap_or(dst->low_slices, dst->low_slices, src->low_slices,
>> + SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH) {
>> bitmap_or(result, dst->high_slices, src->high_slices,
>> SLICE_NUM_HIGH);
>> @@ -409,7 +419,8 @@ static inline void slice_andnot_mask(struct slice_mask *dst, struct slice_mask *
>> {
>> DECLARE_BITMAP(result, SLICE_NUM_HIGH);
>>
>> - dst->low_slices &= ~src->low_slices;
>> + bitmap_andnot(dst->low_slices, dst->low_slices, src->low_slices,
>> + SLICE_NUM_LOW);
>>
>> if (SLICE_NUM_HIGH) {
>> bitmap_andnot(result, dst->high_slices, src->high_slices,
>> @@ -464,16 +475,16 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
>> /*
>> * init different masks
>> */
>> - mask.low_slices = 0;
>> + bitmap_zero(mask.low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(mask.high_slices, SLICE_NUM_HIGH);
>>
>> /* silence stupid warning */;
>> - potential_mask.low_slices = 0;
>> + bitmap_zero(potential_mask.low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(potential_mask.high_slices, SLICE_NUM_HIGH);
>>
>> - compat_mask.low_slices = 0;
>> + bitmap_zero(compat_mask.low_slices, SLICE_NUM_LOW);
>> if (SLICE_NUM_HIGH)
>> bitmap_zero(compat_mask.high_slices, SLICE_NUM_HIGH);
>>
>> @@ -613,7 +624,7 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len,
>> convert:
>> slice_andnot_mask(&mask, &good_mask);
>> slice_andnot_mask(&mask, &compat_mask);
>> - if (mask.low_slices ||
>> + if (!bitmap_empty(mask.low_slices, SLICE_NUM_LOW) ||
>> (SLICE_NUM_HIGH &&
>> !bitmap_empty(mask.high_slices, SLICE_NUM_HIGH))) {
>> slice_convert(mm, mask, psize);
>> @@ -647,7 +658,7 @@ unsigned long arch_get_unmapped_area_topdown(struct file *filp,
>>
>> unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
>> {
>> - unsigned char *hpsizes;
>> + unsigned char *psizes;
>> int index, mask_index;
>>
>> /*
>> @@ -661,15 +672,14 @@ unsigned int get_slice_psize(struct mm_struct *mm, unsigned long addr)
>> #endif
>> }
>> if (addr <= SLICE_LOW_TOP) {
>> - u64 lpsizes;
>> - lpsizes = mm->context.low_slices_psize;
>> + psizes = mm->context.low_slices_psize;
>> index = GET_LOW_SLICE_INDEX(addr);
>> - return (lpsizes >> (index * 4)) & 0xf;
>> + } else {
>> + psizes = mm->context.high_slices_psize;
>> + index = GET_HIGH_SLICE_INDEX(addr);
>> }
>> - hpsizes = mm->context.high_slices_psize;
>> - index = GET_HIGH_SLICE_INDEX(addr);
>> mask_index = index & 0x1;
>> - return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xf;
>> + return (psizes[index >> 1] >> (mask_index * 4)) & 0xf;
>> }
>> EXPORT_SYMBOL_GPL(get_slice_psize);
>>
>> @@ -690,8 +700,8 @@ EXPORT_SYMBOL_GPL(get_slice_psize);
>> void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
>> {
>> int index, mask_index;
>> - unsigned char *hpsizes;
>> - unsigned long flags, lpsizes;
>> + unsigned char *hpsizes, *lpsizes;
>> + unsigned long flags;
>> unsigned int old_psize;
>> int i;
>>
>> @@ -709,12 +719,14 @@ void slice_set_user_psize(struct mm_struct *mm, unsigned int psize)
>> wmb();
>>
>> lpsizes = mm->context.low_slices_psize;
>> - for (i = 0; i < SLICE_NUM_LOW; i++)
>> - if (((lpsizes >> (i * 4)) & 0xf) == old_psize)
>> - lpsizes = (lpsizes & ~(0xful << (i * 4))) |
>> - (((unsigned long)psize) << (i * 4));
>> - /* Assign the value back */
>> - mm->context.low_slices_psize = lpsizes;
>> + for (i = 0; i < SLICE_NUM_LOW; i++) {
>> + mask_index = i & 0x1;
>> + index = i >> 1;
>> + if (((lpsizes[index] >> (mask_index * 4)) & 0xf) == old_psize)
>> + lpsizes[index] = (lpsizes[index] &
>> + ~(0xf << (mask_index * 4))) |
>> + (((unsigned long)psize) << (mask_index * 4));
>> + }
>>
>> hpsizes = mm->context.high_slices_psize;
>> for (i = 0; i < SLICE_NUM_HIGH; i++) {
>> --
>> 2.13.3
On 01/16/2018 10:01 PM, Christophe LEROY wrote:
>
>>> diff --git a/arch/powerpc/include/asm/page_64.h
>>> b/arch/powerpc/include/asm/page_64.h
>>> index 56234c6fcd61..a7baef5bbe5f 100644
>>> --- a/arch/powerpc/include/asm/page_64.h
>>> +++ b/arch/powerpc/include/asm/page_64.h
>>> @@ -91,30 +91,13 @@ extern u64 ppc64_pft_size;
>>> #define SLICE_LOW_SHIFT 28
>>> #define SLICE_HIGH_SHIFT 40
>>> -#define SLICE_LOW_TOP (0x100000000ul)
>>> -#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
>>> +#define SLICE_LOW_TOP (0xfffffffful)
>>> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
>>> #define SLICE_NUM_HIGH (H_PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
>>
>>
>> Why are you changing this? is this a bug fix?
>
> That's because 0x100000000ul is out of range of unsigned long on PPC32.
Ok that detail was important. I missed that.
>
>>
>>> #define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
>>> #define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
>>> -#ifndef __ASSEMBLY__
>>> -struct mm_struct;
>>> -
>>> -extern unsigned long slice_get_unmapped_area(unsigned long addr,
>>> - unsigned long len,
>>> - unsigned long flags,
>>> - unsigned int psize,
>>> - int topdown);
>>> -
>>> -extern unsigned int get_slice_psize(struct mm_struct *mm,
>>> - unsigned long addr);
>>> -
>>> -extern void slice_set_user_psize(struct mm_struct *mm, unsigned int
>>> psize);
>>> -extern void slice_set_range_psize(struct mm_struct *mm, unsigned
>>> long start,
>>> - unsigned long len, unsigned int psize);
>>> -
>>> -#endif /* __ASSEMBLY__ */
>>> #else
>>> #define slice_init()
>>> #ifdef CONFIG_PPC_BOOK3S_64
>>> diff --git a/arch/powerpc/kernel/setup-common.c
>>> b/arch/powerpc/kernel/setup-common.c
>>> index 9d213542a48b..a285e1067713 100644
>>> --- a/arch/powerpc/kernel/setup-common.c
>>> +++ b/arch/powerpc/kernel/setup-common.c
>>> @@ -928,7 +928,7 @@ void __init setup_arch(char **cmdline_p)
>>> if (!radix_enabled())
>>> init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
>>> #else
>>> -#error "context.addr_limit not initialized."
>>> + init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
>>> #endif
>>
>>
>> May be put this within #ifdef 8XX and retain the error?
>
> Is this error really worth it ?
> I wanted to avoid spreading too many #ifdef PPC_8xx, but ok I can do that.
>
>>
>>> #endif
>>> diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
>>> index f29212e40f40..0be77709446c 100644
>>> --- a/arch/powerpc/mm/8xx_mmu.c
>>> +++ b/arch/powerpc/mm/8xx_mmu.c
>>> @@ -192,7 +192,7 @@ void set_context(unsigned long id, pgd_t *pgd)
>>> mtspr(SPRN_M_TW, __pa(pgd) - offset);
>>> /* Update context */
>>> - mtspr(SPRN_M_CASID, id);
>>> + mtspr(SPRN_M_CASID, id - 1);
>>> /* sync */
>>> mb();
>>> }
>>> diff --git a/arch/powerpc/mm/hash_utils_64.c
>>> b/arch/powerpc/mm/hash_utils_64.c
>>> index 655a5a9a183d..3266b3326088 100644
>>> --- a/arch/powerpc/mm/hash_utils_64.c
>>> +++ b/arch/powerpc/mm/hash_utils_64.c
>>> @@ -1101,7 +1101,7 @@ static unsigned int get_paca_psize(unsigned
>>> long addr)
>>> unsigned char *hpsizes;
>>> unsigned long index, mask_index;
>>> - if (addr < SLICE_LOW_TOP) {
>>> + if (addr <= SLICE_LOW_TOP) {
>>
>> If this is part of bug fix, please do it as part of seperate patch
>> with details
>
> As explained above, in order to allow comparison to work on PPC32,
> SLICE_LOW_TOP has to be 0xffffffff instead of 0x100000000
>
> How should I split in separate patches ? Something like ?
> 1/ Slice support for PPC32 > 2/ Activate slice for 8xx
Yes something like that. Will you be able to avoid that
if (SLICE_NUM_HIGH) from the code? That makes the code ugly. Right now
i don't have definite suggestion on what we could do though.
-aneesh
On 01/16/2018 10:01 PM, Christophe LEROY wrote:
>
>
> Le 16/01/2018 à 16:49, Aneesh Kumar K.V a écrit :
>> Christophe Leroy <[email protected]> writes:
>>
>>> When an app has some regular pages allocated (e.g. see below) and tries
>>> to mmap() a huge page at a hint address covered by the same PMD entry,
>>> the kernel accepts the hint allthough the 8xx cannot handle different
>>> page sizes in the same PMD entry.
>>
>>
>> So that is a bug in get_unmapped_area function that you are using and
>> you want to fix that by using the slice code. Can you describe here what
>> the allocation restrictions are w.r.t 8xx? Do they have segments and
>> base page size like hash64?
>
> I don't think it is a bug in get_unmapped_area() that is used by
> default. It is that some HW do support mixing any page size in the same
> page table (eg BOOK3E ?), but the 8xx doesn't.
> In the 8xx, the page size is defined in the PGD entry, then all pages
> defined in a given page table pointed by a PGD entry have the same size.
>
> So it is similar to segments if you consider each PGD entry as a kind of
> segment
>
so IIUC, hugepd format encodes the page size details and that require us
to ensure that all the address range mapped at that hupge_pd entry is of
same page size? Hence we want to avoid mmap handing over an address in
that range when we already have a hugetlb mapping in that range?
-aneesh
Le 16/01/2018 à 17:43, Aneesh Kumar K.V a écrit :
>
>
> On 01/16/2018 10:01 PM, Christophe LEROY wrote:
>>
>>
>> Le 16/01/2018 à 16:49, Aneesh Kumar K.V a écrit :
>>> Christophe Leroy <[email protected]> writes:
>>>
>>>> When an app has some regular pages allocated (e.g. see below) and tries
>>>> to mmap() a huge page at a hint address covered by the same PMD entry,
>>>> the kernel accepts the hint allthough the 8xx cannot handle different
>>>> page sizes in the same PMD entry.
>>>
>>>
>>> So that is a bug in get_unmapped_area function that you are using and
>>> you want to fix that by using the slice code. Can you describe here what
>>> the allocation restrictions are w.r.t 8xx? Do they have segments and
>>> base page size like hash64?
>>
>> I don't think it is a bug in get_unmapped_area() that is used by
>> default. It is that some HW do support mixing any page size in the
>> same page table (eg BOOK3E ?), but the 8xx doesn't.
>> In the 8xx, the page size is defined in the PGD entry, then all pages
>> defined in a given page table pointed by a PGD entry have the same size.
>>
>> So it is similar to segments if you consider each PGD entry as a kind
>> of segment
>>
>
> so IIUC, hugepd format encodes the page size details and that require us
> to ensure that all the address range mapped at that hupge_pd entry is of
> same page size? Hence we want to avoid mmap handing over an address in
> that range when we already have a hugetlb mapping in that range?
Exactly
And also avoid hugetlb_get_unmapped_area() accepting an hint address in
that range when we already have a regular mapping in that range.
Christophe
Le 16/01/2018 à 17:41, Aneesh Kumar K.V a écrit :
>
>
> On 01/16/2018 10:01 PM, Christophe LEROY wrote:
>>
>>>> diff --git a/arch/powerpc/include/asm/page_64.h
>>>> b/arch/powerpc/include/asm/page_64.h
>>>> index 56234c6fcd61..a7baef5bbe5f 100644
>>>> --- a/arch/powerpc/include/asm/page_64.h
>>>> +++ b/arch/powerpc/include/asm/page_64.h
>>>> @@ -91,30 +91,13 @@ extern u64 ppc64_pft_size;
>>>> #define SLICE_LOW_SHIFT 28
>>>> #define SLICE_HIGH_SHIFT 40
>>>> -#define SLICE_LOW_TOP (0x100000000ul)
>>>> -#define SLICE_NUM_LOW (SLICE_LOW_TOP >> SLICE_LOW_SHIFT)
>>>> +#define SLICE_LOW_TOP (0xfffffffful)
>>>> +#define SLICE_NUM_LOW ((SLICE_LOW_TOP >> SLICE_LOW_SHIFT) + 1)
>>>> #define SLICE_NUM_HIGH (H_PGTABLE_RANGE >> SLICE_HIGH_SHIFT)
>>>
>>>
>>> Why are you changing this? is this a bug fix?
>>
>> That's because 0x100000000ul is out of range of unsigned long on PPC32.
>
> Ok that detail was important. I missed that.
>
>>
>>>
>>>> #define GET_LOW_SLICE_INDEX(addr) ((addr) >> SLICE_LOW_SHIFT)
>>>> #define GET_HIGH_SLICE_INDEX(addr) ((addr) >> SLICE_HIGH_SHIFT)
>>>> -#ifndef __ASSEMBLY__
>>>> -struct mm_struct;
>>>> -
>>>> -extern unsigned long slice_get_unmapped_area(unsigned long addr,
>>>> - unsigned long len,
>>>> - unsigned long flags,
>>>> - unsigned int psize,
>>>> - int topdown);
>>>> -
>>>> -extern unsigned int get_slice_psize(struct mm_struct *mm,
>>>> - unsigned long addr);
>>>> -
>>>> -extern void slice_set_user_psize(struct mm_struct *mm, unsigned int
>>>> psize);
>>>> -extern void slice_set_range_psize(struct mm_struct *mm, unsigned
>>>> long start,
>>>> - unsigned long len, unsigned int psize);
>>>> -
>>>> -#endif /* __ASSEMBLY__ */
>>>> #else
>>>> #define slice_init()
>>>> #ifdef CONFIG_PPC_BOOK3S_64
>>>> diff --git a/arch/powerpc/kernel/setup-common.c
>>>> b/arch/powerpc/kernel/setup-common.c
>>>> index 9d213542a48b..a285e1067713 100644
>>>> --- a/arch/powerpc/kernel/setup-common.c
>>>> +++ b/arch/powerpc/kernel/setup-common.c
>>>> @@ -928,7 +928,7 @@ void __init setup_arch(char **cmdline_p)
>>>> if (!radix_enabled())
>>>> init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW_USER64;
>>>> #else
>>>> -#error "context.addr_limit not initialized."
>>>> + init_mm.context.slb_addr_limit = DEFAULT_MAP_WINDOW;
>>>> #endif
>>>
>>>
>>> May be put this within #ifdef 8XX and retain the error?
>>
>> Is this error really worth it ?
>> I wanted to avoid spreading too many #ifdef PPC_8xx, but ok I can do
>> that.
>>
>>>
>>>> #endif
>>>> diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
>>>> index f29212e40f40..0be77709446c 100644
>>>> --- a/arch/powerpc/mm/8xx_mmu.c
>>>> +++ b/arch/powerpc/mm/8xx_mmu.c
>>>> @@ -192,7 +192,7 @@ void set_context(unsigned long id, pgd_t *pgd)
>>>> mtspr(SPRN_M_TW, __pa(pgd) - offset);
>>>> /* Update context */
>>>> - mtspr(SPRN_M_CASID, id);
>>>> + mtspr(SPRN_M_CASID, id - 1);
>>>> /* sync */
>>>> mb();
>>>> }
>>>> diff --git a/arch/powerpc/mm/hash_utils_64.c
>>>> b/arch/powerpc/mm/hash_utils_64.c
>>>> index 655a5a9a183d..3266b3326088 100644
>>>> --- a/arch/powerpc/mm/hash_utils_64.c
>>>> +++ b/arch/powerpc/mm/hash_utils_64.c
>>>> @@ -1101,7 +1101,7 @@ static unsigned int get_paca_psize(unsigned
>>>> long addr)
>>>> unsigned char *hpsizes;
>>>> unsigned long index, mask_index;
>>>> - if (addr < SLICE_LOW_TOP) {
>>>> + if (addr <= SLICE_LOW_TOP) {
>>>
>>> If this is part of bug fix, please do it as part of seperate patch
>>> with details
>>
>> As explained above, in order to allow comparison to work on PPC32,
>> SLICE_LOW_TOP has to be 0xffffffff instead of 0x100000000
>>
>> How should I split in separate patches ? Something like ?
>> 1/ Slice support for PPC32 > 2/ Activate slice for 8xx
>
> Yes something like that. Will you be able to avoid that
> if (SLICE_NUM_HIGH) from the code? That makes the code ugly. Right now
> i don't have definite suggestion on what we could do though.
>
Could use #ifdefs instead, but in my mind it would be even more ugly.
I would have liked just doing nothing, but the issue is that at the
moment bitmap_xxx() functions are not prepared to handle bitmaps of size
zero. Should we try to change that ? Any chance to succeed ?
Christophe
Christophe LEROY <[email protected]> writes:
>>
>>> How should I split in separate patches ? Something like ?
>>> 1/ Slice support for PPC32 > 2/ Activate slice for 8xx
>>
>> Yes something like that. Will you be able to avoid that
>> if (SLICE_NUM_HIGH) from the code? That makes the code ugly. Right now
>> i don't have definite suggestion on what we could do though.
>>
>
> Could use #ifdefs instead, but in my mind it would be even more ugly.
>
> I would have liked just doing nothing, but the issue is that at the
> moment bitmap_xxx() functions are not prepared to handle bitmaps of size
> zero. Should we try to change that ? Any chance to succeed ?
>
How much code duplication it is to do slice_32.c?
Michael,
What do you suggest here?
-aneesh
Le 17/01/2018 à 06:23, Aneesh Kumar K.V a écrit :
> Christophe LEROY <[email protected]> writes:
>
>>>
>>>> How should I split in separate patches ? Something like ?
>>>> 1/ Slice support for PPC32 > 2/ Activate slice for 8xx
>>>
>>> Yes something like that. Will you be able to avoid that
>>> if (SLICE_NUM_HIGH) from the code? That makes the code ugly. Right now
>>> i don't have definite suggestion on what we could do though.
>>>
>>
>> Could use #ifdefs instead, but in my mind it would be even more ugly.
>>
>> I would have liked just doing nothing, but the issue is that at the
>> moment bitmap_xxx() functions are not prepared to handle bitmaps of size
>> zero. Should we try to change that ? Any chance to succeed ?
>>
>
> How much code duplication it is to do slice_32.c?
Most functions use both .low_slices and .high_slices, so if your thought
is to copy slice.c to slice_32.c and then remove all code handling
.high_slices, we will at least duplicate 50% of the code
In v2 that I have just submitted, I have embedded this ugly test in
macros called slice_bitmap_xxx() which handles the 0 nbits case. Tell me
if it looks better that way.
Christophe
>
> Michael,
>
> What do you suggest here?
>
> -aneesh
>