Fixes sparse warnings:
./include/trace/events/fs_dax.h:10:1: sparse:
got restricted vm_fault_t
./include/trace/events/fs_dax.h:153:1: sparse:
got restricted vm_fault_t
fs/dax.c:563:39: sparse: got restricted vm_fault_t
fs/dax.c:565:39: sparse: got restricted vm_fault_t
fs/dax.c:569:31: sparse: got restricted vm_fault_t
fs/dax.c:1055:41: sparse:
got restricted vm_fault_t [assigned] [usertype] ret
fs/dax.c:1461:46: sparse: got restricted vm_fault_t [usertype] ret
fs/dax.c:1477:21: sparse:
expected restricted vm_fault_t [assigned] [usertype] ret
fs/dax.c:1518:51: sparse:
got restricted vm_fault_t [assigned] [usertype] ret
fs/dax.c:1599:21: sparse:
expected restricted vm_fault_t [assigned] [usertype] ret
fs/dax.c:1633:62: sparse:
got restricted vm_fault_t [assigned] [usertype] ret
fs/dax.c:1696:55: sparse: got restricted vm_fault_t
fs/dax.c:1711:58: sparse:
got restricted vm_fault_t [assigned] [usertype] ret
vm_fault_t type is bitwise and requires __force attribute for any casts.
Signed-off-by: Vasily Averin <[email protected]>
---
fs/dax.c | 22 +++++++++++-----------
include/linux/mm_types.h | 30 ++++++++++++++++--------------
2 files changed, 27 insertions(+), 25 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 67a08a32fccb..eb1a1808f719 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -560,13 +560,13 @@ static void *grab_mapping_entry(struct xa_state *xas,
if (xas_nomem(xas, mapping_gfp_mask(mapping) & ~__GFP_HIGHMEM))
goto retry;
if (xas->xa_node == XA_ERROR(-ENOMEM))
- return xa_mk_internal(VM_FAULT_OOM);
+ return xa_mk_internal((__force unsigned long)VM_FAULT_OOM);
if (xas_error(xas))
- return xa_mk_internal(VM_FAULT_SIGBUS);
+ return xa_mk_internal((__force unsigned long)VM_FAULT_SIGBUS);
return entry;
fallback:
xas_unlock_irq(xas);
- return xa_mk_internal(VM_FAULT_FALLBACK);
+ return xa_mk_internal((__force unsigned long)VM_FAULT_FALLBACK);
}
/**
@@ -1052,7 +1052,7 @@ static vm_fault_t dax_load_hole(struct xa_state *xas,
DAX_ZERO_PAGE, false);
ret = vmf_insert_mixed(vmf->vma, vaddr, pfn);
- trace_dax_load_hole(inode, vmf, ret);
+ trace_dax_load_hole(inode, vmf, (__force int)ret);
return ret;
}
@@ -1458,7 +1458,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
void *entry;
int error;
- trace_dax_pte_fault(iter.inode, vmf, ret);
+ trace_dax_pte_fault(iter.inode, vmf, (__force int)ret);
/*
* Check whether offset isn't beyond end of file now. Caller is supposed
* to hold locks serializing us with truncate / punch hole so this is
@@ -1474,7 +1474,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
entry = grab_mapping_entry(&xas, mapping, 0);
if (xa_is_internal(entry)) {
- ret = xa_to_internal(entry);
+ ret = (__force vm_fault_t)xa_to_internal(entry);
goto out;
}
@@ -1515,7 +1515,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
unlock_entry:
dax_unlock_entry(&xas, entry);
out:
- trace_dax_pte_fault_done(iter.inode, vmf, ret);
+ trace_dax_pte_fault_done(iter.inode, vmf, (__force int)ret);
return ret;
}
@@ -1596,7 +1596,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
*/
entry = grab_mapping_entry(&xas, mapping, PMD_ORDER);
if (xa_is_internal(entry)) {
- ret = xa_to_internal(entry);
+ ret = (__force vm_fault_t)xa_to_internal(entry);
goto fallback;
}
@@ -1630,7 +1630,7 @@ static vm_fault_t dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp,
count_vm_event(THP_FAULT_FALLBACK);
}
out:
- trace_dax_pmd_fault_done(iter.inode, vmf, max_pgoff, ret);
+ trace_dax_pmd_fault_done(iter.inode, vmf, max_pgoff, (__force int)ret);
return ret;
}
#else
@@ -1693,7 +1693,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order)
put_unlocked_entry(&xas, entry, WAKE_NEXT);
xas_unlock_irq(&xas);
trace_dax_insert_pfn_mkwrite_no_entry(mapping->host, vmf,
- VM_FAULT_NOPAGE);
+ (__force int)VM_FAULT_NOPAGE);
return VM_FAULT_NOPAGE;
}
xas_set_mark(&xas, PAGECACHE_TAG_DIRTY);
@@ -1708,7 +1708,7 @@ dax_insert_pfn_mkwrite(struct vm_fault *vmf, pfn_t pfn, unsigned int order)
else
ret = VM_FAULT_FALLBACK;
dax_unlock_entry(&xas, entry);
- trace_dax_insert_pfn_mkwrite(mapping->host, vmf, ret);
+ trace_dax_insert_pfn_mkwrite(mapping->host, vmf, (__force int)ret);
return ret;
}
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 8834e38c06a4..57cc4918b1b1 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -745,20 +745,22 @@ enum vm_fault_reason {
VM_FAULT_SIGSEGV | VM_FAULT_HWPOISON | \
VM_FAULT_HWPOISON_LARGE | VM_FAULT_FALLBACK)
-#define VM_FAULT_RESULT_TRACE \
- { VM_FAULT_OOM, "OOM" }, \
- { VM_FAULT_SIGBUS, "SIGBUS" }, \
- { VM_FAULT_MAJOR, "MAJOR" }, \
- { VM_FAULT_WRITE, "WRITE" }, \
- { VM_FAULT_HWPOISON, "HWPOISON" }, \
- { VM_FAULT_HWPOISON_LARGE, "HWPOISON_LARGE" }, \
- { VM_FAULT_SIGSEGV, "SIGSEGV" }, \
- { VM_FAULT_NOPAGE, "NOPAGE" }, \
- { VM_FAULT_LOCKED, "LOCKED" }, \
- { VM_FAULT_RETRY, "RETRY" }, \
- { VM_FAULT_FALLBACK, "FALLBACK" }, \
- { VM_FAULT_DONE_COW, "DONE_COW" }, \
- { VM_FAULT_NEEDDSYNC, "NEEDDSYNC" }
+#define faultflag_string(flag) {(__force unsigned long)VM_FAULT_##flag, #flag}
+
+#define VM_FAULT_RESULT_TRACE \
+ faultflag_string(OOM), \
+ faultflag_string(SIGBUS), \
+ faultflag_string(MAJOR), \
+ faultflag_string(WRITE), \
+ faultflag_string(HWPOISON), \
+ faultflag_string(HWPOISON_LARGE), \
+ faultflag_string(SIGSEGV), \
+ faultflag_string(NOPAGE), \
+ faultflag_string(LOCKED), \
+ faultflag_string(RETRY), \
+ faultflag_string(FALLBACK), \
+ faultflag_string(DONE_COW), \
+ faultflag_string(NEEDDSYNC)
struct vm_special_mapping {
const char *name; /* The name, e.g. "[vdso]". */
--
2.31.1
On Sat, May 14, 2022 at 05:26:21PM +0300, Vasily Averin wrote:
> Fixes sparse warnings:
> ./include/trace/events/fs_dax.h:10:1: sparse:
> got restricted vm_fault_t
> ./include/trace/events/fs_dax.h:153:1: sparse:
> got restricted vm_fault_t
> fs/dax.c:563:39: sparse: got restricted vm_fault_t
> fs/dax.c:565:39: sparse: got restricted vm_fault_t
> fs/dax.c:569:31: sparse: got restricted vm_fault_t
> fs/dax.c:1055:41: sparse:
> got restricted vm_fault_t [assigned] [usertype] ret
> fs/dax.c:1461:46: sparse: got restricted vm_fault_t [usertype] ret
> fs/dax.c:1477:21: sparse:
> expected restricted vm_fault_t [assigned] [usertype] ret
> fs/dax.c:1518:51: sparse:
> got restricted vm_fault_t [assigned] [usertype] ret
> fs/dax.c:1599:21: sparse:
> expected restricted vm_fault_t [assigned] [usertype] ret
> fs/dax.c:1633:62: sparse:
> got restricted vm_fault_t [assigned] [usertype] ret
> fs/dax.c:1696:55: sparse: got restricted vm_fault_t
> fs/dax.c:1711:58: sparse:
> got restricted vm_fault_t [assigned] [usertype] ret
>
> vm_fault_t type is bitwise and requires __force attribute for any casts.
Well, this patch is all kinds of messy. I would rather we had better
abstractions. For example ...
> @@ -560,13 +560,13 @@ static void *grab_mapping_entry(struct xa_state *xas,
> if (xas_nomem(xas, mapping_gfp_mask(mapping) & ~__GFP_HIGHMEM))
> goto retry;
> if (xas->xa_node == XA_ERROR(-ENOMEM))
> - return xa_mk_internal(VM_FAULT_OOM);
> + return xa_mk_internal((__force unsigned long)VM_FAULT_OOM);
> if (xas_error(xas))
> - return xa_mk_internal(VM_FAULT_SIGBUS);
> + return xa_mk_internal((__force unsigned long)VM_FAULT_SIGBUS);
> return entry;
> fallback:
> xas_unlock_irq(xas);
> - return xa_mk_internal(VM_FAULT_FALLBACK);
> + return xa_mk_internal((__force unsigned long)VM_FAULT_FALLBACK);
> }
return vm_fault_encode(VM_FAULT_xxx);
> /**
> @@ -1052,7 +1052,7 @@ static vm_fault_t dax_load_hole(struct xa_state *xas,
> DAX_ZERO_PAGE, false);
>
> ret = vmf_insert_mixed(vmf->vma, vaddr, pfn);
> - trace_dax_load_hole(inode, vmf, ret);
> + trace_dax_load_hole(inode, vmf, (__force int)ret);
Seems like trace_dax_load_hole() should take a vm_fault_t?
> - trace_dax_pte_fault(iter.inode, vmf, ret);
> + trace_dax_pte_fault(iter.inode, vmf, (__force int)ret);
Ditto.
> @@ -1474,7 +1474,7 @@ static vm_fault_t dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp,
>
> entry = grab_mapping_entry(&xas, mapping, 0);
> if (xa_is_internal(entry)) {
> - ret = xa_to_internal(entry);
> + ret = (__force vm_fault_t)xa_to_internal(entry);
vm_fault_decode(entry)?
... the others seem like more of the same. So I'm in favour of what
you're doing, but would rather it were done differently. Generally
seeing __force casts in the body of a function is a sign that things are
wrong; it's better to have them hidden in abstractions.