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authorIngo Molnar <mingo@kernel.org>2016-01-29 09:41:18 +0100
committerIngo Molnar <mingo@kernel.org>2016-01-29 09:41:18 +0100
commit76b36fa896a2db64582690e085f36adc76604134 (patch)
tree78007f123ead6f96cdee6ba98ac3c289c706cc39 /mm/mmap.c
parent14365449b6ce34cf6a3040ff8ebbb39d89d67159 (diff)
parent92e963f50fc74041b5e9e744c330dca48e04f08d (diff)
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Merge tag 'v4.5-rc1' into x86/asm, to refresh the branch before merging new changes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'mm/mmap.c')
-rw-r--r--mm/mmap.c106
1 files changed, 62 insertions, 44 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index f717453b1a57..407ab434d5ee 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -58,6 +58,18 @@
#define arch_rebalance_pgtables(addr, len) (addr)
#endif
+#ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
+const int mmap_rnd_bits_min = CONFIG_ARCH_MMAP_RND_BITS_MIN;
+const int mmap_rnd_bits_max = CONFIG_ARCH_MMAP_RND_BITS_MAX;
+int mmap_rnd_bits __read_mostly = CONFIG_ARCH_MMAP_RND_BITS;
+#endif
+#ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
+const int mmap_rnd_compat_bits_min = CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MIN;
+const int mmap_rnd_compat_bits_max = CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX;
+int mmap_rnd_compat_bits __read_mostly = CONFIG_ARCH_MMAP_RND_COMPAT_BITS;
+#endif
+
+
static void unmap_region(struct mm_struct *mm,
struct vm_area_struct *vma, struct vm_area_struct *prev,
unsigned long start, unsigned long end);
@@ -1208,24 +1220,6 @@ none:
return NULL;
}
-#ifdef CONFIG_PROC_FS
-void vm_stat_account(struct mm_struct *mm, unsigned long flags,
- struct file *file, long pages)
-{
- const unsigned long stack_flags
- = VM_STACK_FLAGS & (VM_GROWSUP|VM_GROWSDOWN);
-
- mm->total_vm += pages;
-
- if (file) {
- mm->shared_vm += pages;
- if ((flags & (VM_EXEC|VM_WRITE)) == VM_EXEC)
- mm->exec_vm += pages;
- } else if (flags & stack_flags)
- mm->stack_vm += pages;
-}
-#endif /* CONFIG_PROC_FS */
-
/*
* If a hint addr is less than mmap_min_addr change hint to be as
* low as possible but still greater than mmap_min_addr
@@ -1544,19 +1538,17 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
unsigned long charged = 0;
/* Check against address space limit. */
- if (!may_expand_vm(mm, len >> PAGE_SHIFT)) {
+ if (!may_expand_vm(mm, vm_flags, len >> PAGE_SHIFT)) {
unsigned long nr_pages;
/*
* MAP_FIXED may remove pages of mappings that intersects with
* requested mapping. Account for the pages it would unmap.
*/
- if (!(vm_flags & MAP_FIXED))
- return -ENOMEM;
-
nr_pages = count_vma_pages_range(mm, addr, addr + len);
- if (!may_expand_vm(mm, (len >> PAGE_SHIFT) - nr_pages))
+ if (!may_expand_vm(mm, vm_flags,
+ (len >> PAGE_SHIFT) - nr_pages))
return -ENOMEM;
}
@@ -1655,7 +1647,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
out:
perf_event_mmap(vma);
- vm_stat_account(mm, vm_flags, file, len >> PAGE_SHIFT);
+ vm_stat_account(mm, vm_flags, len >> PAGE_SHIFT);
if (vm_flags & VM_LOCKED) {
if (!((vm_flags & VM_SPECIAL) || is_vm_hugetlb_page(vma) ||
vma == get_gate_vma(current->mm)))
@@ -2102,7 +2094,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns
unsigned long new_start, actual_size;
/* address space limit tests */
- if (!may_expand_vm(mm, grow))
+ if (!may_expand_vm(mm, vma->vm_flags, grow))
return -ENOMEM;
/* Stack limit test */
@@ -2199,8 +2191,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
spin_lock(&mm->page_table_lock);
if (vma->vm_flags & VM_LOCKED)
mm->locked_vm += grow;
- vm_stat_account(mm, vma->vm_flags,
- vma->vm_file, grow);
+ vm_stat_account(mm, vma->vm_flags, grow);
anon_vma_interval_tree_pre_update_vma(vma);
vma->vm_end = address;
anon_vma_interval_tree_post_update_vma(vma);
@@ -2275,8 +2266,7 @@ int expand_downwards(struct vm_area_struct *vma,
spin_lock(&mm->page_table_lock);
if (vma->vm_flags & VM_LOCKED)
mm->locked_vm += grow;
- vm_stat_account(mm, vma->vm_flags,
- vma->vm_file, grow);
+ vm_stat_account(mm, vma->vm_flags, grow);
anon_vma_interval_tree_pre_update_vma(vma);
vma->vm_start = address;
vma->vm_pgoff -= grow;
@@ -2390,7 +2380,7 @@ static void remove_vma_list(struct mm_struct *mm, struct vm_area_struct *vma)
if (vma->vm_flags & VM_ACCOUNT)
nr_accounted += nrpages;
- vm_stat_account(mm, vma->vm_flags, vma->vm_file, -nrpages);
+ vm_stat_account(mm, vma->vm_flags, -nrpages);
vma = remove_vma(vma);
} while (vma);
vm_unacct_memory(nr_accounted);
@@ -2760,7 +2750,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
}
/* Check against address space limits *after* clearing old maps... */
- if (!may_expand_vm(mm, len >> PAGE_SHIFT))
+ if (!may_expand_vm(mm, flags, len >> PAGE_SHIFT))
return -ENOMEM;
if (mm->map_count > sysctl_max_map_count)
@@ -2795,6 +2785,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len)
out:
perf_event_mmap(vma);
mm->total_vm += len >> PAGE_SHIFT;
+ mm->data_vm += len >> PAGE_SHIFT;
if (flags & VM_LOCKED)
mm->locked_vm += (len >> PAGE_SHIFT);
vma->vm_flags |= VM_SOFTDIRTY;
@@ -2986,16 +2977,28 @@ out:
* Return true if the calling process may expand its vm space by the passed
* number of pages
*/
-int may_expand_vm(struct mm_struct *mm, unsigned long npages)
+bool may_expand_vm(struct mm_struct *mm, vm_flags_t flags, unsigned long npages)
{
- unsigned long cur = mm->total_vm; /* pages */
- unsigned long lim;
+ if (mm->total_vm + npages > rlimit(RLIMIT_AS) >> PAGE_SHIFT)
+ return false;
- lim = rlimit(RLIMIT_AS) >> PAGE_SHIFT;
+ if ((flags & (VM_WRITE | VM_SHARED | (VM_STACK_FLAGS &
+ (VM_GROWSUP | VM_GROWSDOWN)))) == VM_WRITE)
+ return mm->data_vm + npages <= rlimit(RLIMIT_DATA);
- if (cur + npages > lim)
- return 0;
- return 1;
+ return true;
+}
+
+void vm_stat_account(struct mm_struct *mm, vm_flags_t flags, long npages)
+{
+ mm->total_vm += npages;
+
+ if ((flags & (VM_EXEC | VM_WRITE)) == VM_EXEC)
+ mm->exec_vm += npages;
+ else if (flags & (VM_STACK_FLAGS & (VM_GROWSUP | VM_GROWSDOWN)))
+ mm->stack_vm += npages;
+ else if ((flags & (VM_WRITE | VM_SHARED)) == VM_WRITE)
+ mm->data_vm += npages;
}
static int special_mapping_fault(struct vm_area_struct *vma,
@@ -3082,7 +3085,7 @@ static struct vm_area_struct *__install_special_mapping(
if (ret)
goto out;
- mm->total_vm += len >> PAGE_SHIFT;
+ vm_stat_account(mm, vma->vm_flags, len >> PAGE_SHIFT);
perf_event_mmap(vma);
@@ -3186,10 +3189,16 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)
* mapping->flags avoid to take the same lock twice, if more than one
* vma in this mm is backed by the same anon_vma or address_space.
*
- * We can take all the locks in random order because the VM code
- * taking i_mmap_rwsem or anon_vma->rwsem outside the mmap_sem never
- * takes more than one of them in a row. Secondly we're protected
- * against a concurrent mm_take_all_locks() by the mm_all_locks_mutex.
+ * We take locks in following order, accordingly to comment at beginning
+ * of mm/rmap.c:
+ * - all hugetlbfs_i_mmap_rwsem_key locks (aka mapping->i_mmap_rwsem for
+ * hugetlb mapping);
+ * - all i_mmap_rwsem locks;
+ * - all anon_vma->rwseml
+ *
+ * We can take all locks within these types randomly because the VM code
+ * doesn't nest them and we protected from parallel mm_take_all_locks() by
+ * mm_all_locks_mutex.
*
* mm_take_all_locks() and mm_drop_all_locks are expensive operations
* that may have to take thousand of locks.
@@ -3208,7 +3217,16 @@ int mm_take_all_locks(struct mm_struct *mm)
for (vma = mm->mmap; vma; vma = vma->vm_next) {
if (signal_pending(current))
goto out_unlock;
- if (vma->vm_file && vma->vm_file->f_mapping)
+ if (vma->vm_file && vma->vm_file->f_mapping &&
+ is_vm_hugetlb_page(vma))
+ vm_lock_mapping(mm, vma->vm_file->f_mapping);
+ }
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ if (signal_pending(current))
+ goto out_unlock;
+ if (vma->vm_file && vma->vm_file->f_mapping &&
+ !is_vm_hugetlb_page(vma))
vm_lock_mapping(mm, vma->vm_file->f_mapping);
}