2020-05-20 05:31:58

by Michel Lespinasse

[permalink] [raw]
Subject: [PATCH v6 05/12] mmap locking API: convert mmap_sem call sites missed by coccinelle

Convert the last few remaining mmap_sem rwsem calls to use the new
mmap locking API. These were missed by coccinelle for some reason
(I think coccinelle does not support some of the preprocessor
constructs in these files ?)

Signed-off-by: Michel Lespinasse <[email protected]>
Reviewed-by: Daniel Jordan <[email protected]>
Reviewed-by: Laurent Dufour <[email protected]>
Reviewed-by: Vlastimil Babka <[email protected]>
---
arch/mips/mm/fault.c | 10 +++++-----
arch/riscv/mm/pageattr.c | 4 ++--
arch/x86/kvm/mmu/paging_tmpl.h | 8 ++++----
fs/proc/base.c | 6 +++---
4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index f8d62cd83b36..9ef2dd39111e 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -97,7 +97,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
if (user_mode(regs))
flags |= FAULT_FLAG_USER;
retry:
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
vma = find_vma(mm, address);
if (!vma)
goto bad_area;
@@ -190,7 +190,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
}
}

- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
return;

/*
@@ -198,7 +198,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
* Fix it, but check if it's kernel or user first..
*/
bad_area:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);

bad_area_nosemaphore:
/* User mode accesses just cause a SIGSEGV */
@@ -250,14 +250,14 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
* We ran out of memory, call the OOM killer, and return the userspace
* (which will retry the fault, or kill us if we got oom-killed).
*/
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
if (!user_mode(regs))
goto no_context;
pagefault_out_of_memory();
return;

do_sigbus:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);

/* Kernel mode? Handle exceptions or die */
if (!user_mode(regs))
diff --git a/arch/riscv/mm/pageattr.c b/arch/riscv/mm/pageattr.c
index 728759eb530a..b9072c043222 100644
--- a/arch/riscv/mm/pageattr.c
+++ b/arch/riscv/mm/pageattr.c
@@ -117,10 +117,10 @@ static int __set_memory(unsigned long addr, int numpages, pgprot_t set_mask,
if (!numpages)
return 0;

- down_read(&init_mm.mmap_sem);
+ mmap_read_lock(&init_mm);
ret = walk_page_range_novma(&init_mm, start, end, &pageattr_ops, NULL,
&masks);
- up_read(&init_mm.mmap_sem);
+ mmap_read_unlock(&init_mm);

flush_tlb_kernel_range(start, end);

diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 9bdf9b7d9a96..40e5bb67cc09 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -165,22 +165,22 @@ static int FNAME(cmpxchg_gpte)(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu,
unsigned long pfn;
unsigned long paddr;

- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
vma = find_vma_intersection(current->mm, vaddr, vaddr + PAGE_SIZE);
if (!vma || !(vma->vm_flags & VM_PFNMAP)) {
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
return -EFAULT;
}
pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
paddr = pfn << PAGE_SHIFT;
table = memremap(paddr, PAGE_SIZE, MEMREMAP_WB);
if (!table) {
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
return -EFAULT;
}
ret = CMPXCHG(&table[index], orig_pte, new_pte);
memunmap(table);
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
}

return (ret != orig_pte);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 9a68032d8d73..a96377557db7 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2314,7 +2314,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
if (!mm)
goto out_put_task;

- ret = down_read_killable(&mm->mmap_sem);
+ ret = mmap_read_lock_killable(mm);
if (ret) {
mmput(mm);
goto out_put_task;
@@ -2341,7 +2341,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
p = genradix_ptr_alloc(&fa, nr_files++, GFP_KERNEL);
if (!p) {
ret = -ENOMEM;
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
mmput(mm);
goto out_put_task;
}
@@ -2350,7 +2350,7 @@ proc_map_files_readdir(struct file *file, struct dir_context *ctx)
p->end = vma->vm_end;
p->mode = vma->vm_file->f_mode;
}
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
mmput(mm);

for (i = 0; i < nr_files; i++) {
--
2.26.2.761.g0e0b3e54be-goog


2020-05-21 03:27:45

by Andrew Morton

[permalink] [raw]
Subject: Re: [PATCH v6 05/12] mmap locking API: convert mmap_sem call sites missed by coccinelle

On Tue, 19 May 2020 22:29:01 -0700 Michel Lespinasse <[email protected]> wrote:

> Convert the last few remaining mmap_sem rwsem calls to use the new
> mmap locking API. These were missed by coccinelle for some reason
> (I think coccinelle does not support some of the preprocessor
> constructs in these files ?)


From: Andrew Morton <[email protected]>
Subject: mmap-locking-api-convert-mmap_sem-call-sites-missed-by-coccinelle-fix

convert linux-next leftovers

Cc: Michel Lespinasse <[email protected]>
Cc: Daniel Jordan <[email protected]>
Cc: Laurent Dufour <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Jerome Glisse <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Liam Howlett <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ying Han <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

arch/arm64/kvm/mmu.c | 14 +++++++-------
lib/test_hmm.c | 14 +++++++-------
2 files changed, 14 insertions(+), 14 deletions(-)

--- a/lib/test_hmm.c~mmap-locking-api-convert-mmap_sem-call-sites-missed-by-coccinelle-fix
+++ a/lib/test_hmm.c
@@ -243,9 +243,9 @@ static int dmirror_range_fault(struct dm
}

range->notifier_seq = mmu_interval_read_begin(range->notifier);
- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
ret = hmm_range_fault(range);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
if (ret) {
if (ret == -EBUSY)
continue;
@@ -684,7 +684,7 @@ static int dmirror_migrate(struct dmirro
if (!mmget_not_zero(mm))
return -EINVAL;

- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
for (addr = start; addr < end; addr = next) {
vma = find_vma(mm, addr);
if (!vma || addr < vma->vm_start ||
@@ -711,7 +711,7 @@ static int dmirror_migrate(struct dmirro
dmirror_migrate_finalize_and_map(&args, dmirror);
migrate_vma_finalize(&args);
}
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
mmput(mm);

/* Return the migrated data for verification. */
@@ -731,7 +731,7 @@ static int dmirror_migrate(struct dmirro
return ret;

out:
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
mmput(mm);
return ret;
}
@@ -823,9 +823,9 @@ static int dmirror_range_snapshot(struct

range->notifier_seq = mmu_interval_read_begin(range->notifier);

- down_read(&mm->mmap_sem);
+ mmap_read_lock(mm);
ret = hmm_range_fault(range);
- up_read(&mm->mmap_sem);
+ mmap_read_unlock(mm);
if (ret) {
if (ret == -EBUSY)
continue;
--- a/arch/arm64/kvm/mmu.c~mmap-locking-api-convert-mmap_sem-call-sites-missed-by-coccinelle-fix
+++ a/arch/arm64/kvm/mmu.c
@@ -1084,7 +1084,7 @@ void stage2_unmap_vm(struct kvm *kvm)
int idx;

idx = srcu_read_lock(&kvm->srcu);
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
spin_lock(&kvm->mmu_lock);

slots = kvm_memslots(kvm);
@@ -1092,7 +1092,7 @@ void stage2_unmap_vm(struct kvm *kvm)
stage2_unmap_memslot(kvm, memslot);

spin_unlock(&kvm->mmu_lock);
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
srcu_read_unlock(&kvm->srcu, idx);
}

@@ -1848,11 +1848,11 @@ static int user_mem_abort(struct kvm_vcp
}

/* Let's check if we will get back a huge page backed by hugetlbfs */
- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
vma = find_vma_intersection(current->mm, hva, hva + 1);
if (unlikely(!vma)) {
kvm_err("Failed to find VMA for hva 0x%lx\n", hva);
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
return -EFAULT;
}

@@ -1879,7 +1879,7 @@ static int user_mem_abort(struct kvm_vcp
if (vma_pagesize == PMD_SIZE ||
(vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm)))
gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT;
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);

/* We need minimum second+third level pages */
ret = mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm),
@@ -2456,7 +2456,7 @@ int kvm_arch_prepare_memory_region(struc
(kvm_phys_size(kvm) >> PAGE_SHIFT))
return -EFAULT;

- down_read(&current->mm->mmap_sem);
+ mmap_read_lock(current->mm);
/*
* A memory region could potentially cover multiple VMAs, and any holes
* between them, so iterate over all of them to find out if we can map
@@ -2515,7 +2515,7 @@ int kvm_arch_prepare_memory_region(struc
stage2_flush_memslot(kvm, memslot);
spin_unlock(&kvm->mmu_lock);
out:
- up_read(&current->mm->mmap_sem);
+ mmap_read_unlock(current->mm);
return ret;
}

_

2020-05-21 04:51:55

by Michel Lespinasse

[permalink] [raw]
Subject: Re: [PATCH v6 05/12] mmap locking API: convert mmap_sem call sites missed by coccinelle

Looks good. I'm not sure if you need a review, but just in case:

On Wed, May 20, 2020 at 8:23 PM Andrew Morton <[email protected]> wrote:
> On Tue, 19 May 2020 22:29:01 -0700 Michel Lespinasse <[email protected]> wrote:
>
> > Convert the last few remaining mmap_sem rwsem calls to use the new
> > mmap locking API. These were missed by coccinelle for some reason
> > (I think coccinelle does not support some of the preprocessor
> > constructs in these files ?)
>
> From: Andrew Morton <[email protected]>
> Subject: mmap-locking-api-convert-mmap_sem-call-sites-missed-by-coccinelle-fix
>
> convert linux-next leftovers
>
> Cc: Michel Lespinasse <[email protected]>
> Cc: Daniel Jordan <[email protected]>
> Cc: Laurent Dufour <[email protected]>
> Cc: Vlastimil Babka <[email protected]>
> Cc: Davidlohr Bueso <[email protected]>
> Cc: David Rientjes <[email protected]>
> Cc: Hugh Dickins <[email protected]>
> Cc: Jason Gunthorpe <[email protected]>
> Cc: Jerome Glisse <[email protected]>
> Cc: John Hubbard <[email protected]>
> Cc: Liam Howlett <[email protected]>
> Cc: Matthew Wilcox <[email protected]>
> Cc: Peter Zijlstra <[email protected]>
> Cc: Ying Han <[email protected]>
> Signed-off-by: Andrew Morton <[email protected]>

Reviewed-by: Michel Lespinasse <[email protected]>