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Diffstat (limited to 'mm')
-rw-r--r--mm/memory.c2
-rw-r--r--mm/mlock.c47
-rw-r--r--mm/mmap.c48
-rw-r--r--mm/page-writeback.c21
-rw-r--r--mm/shmem.c2
-rw-r--r--mm/slub.c2
6 files changed, 45 insertions, 77 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 22bfa7a47a0..baa999e87cd 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1999,7 +1999,7 @@ gotten:
* Don't let another task, with possibly unlocked vma,
* keep the mlocked page.
*/
- if (vma->vm_flags & VM_LOCKED) {
+ if ((vma->vm_flags & VM_LOCKED) && old_page) {
lock_page(old_page); /* for LRU manipulation */
clear_page_mlock(old_page);
unlock_page(old_page);
diff --git a/mm/mlock.c b/mm/mlock.c
index 2904a347e47..028ec482fdd 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -294,14 +294,10 @@ static inline int __mlock_posix_error_return(long retval)
*
* return number of pages [> 0] to be removed from locked_vm on success
* of "special" vmas.
- *
- * return negative error if vma spanning @start-@range disappears while
- * mmap semaphore is dropped. Unlikely?
*/
long mlock_vma_pages_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
- struct mm_struct *mm = vma->vm_mm;
int nr_pages = (end - start) / PAGE_SIZE;
BUG_ON(!(vma->vm_flags & VM_LOCKED));
@@ -314,20 +310,8 @@ long mlock_vma_pages_range(struct vm_area_struct *vma,
if (!((vma->vm_flags & (VM_DONTEXPAND | VM_RESERVED)) ||
is_vm_hugetlb_page(vma) ||
vma == get_gate_vma(current))) {
- long error;
- downgrade_write(&mm->mmap_sem);
-
- error = __mlock_vma_pages_range(vma, start, end, 1);
- up_read(&mm->mmap_sem);
- /* vma can change or disappear */
- down_write(&mm->mmap_sem);
- vma = find_vma(mm, start);
- /* non-NULL vma must contain @start, but need to check @end */
- if (!vma || end > vma->vm_end)
- return -ENOMEM;
-
- return 0; /* hide other errors from mmap(), et al */
+ return __mlock_vma_pages_range(vma, start, end, 1);
}
/*
@@ -438,41 +422,14 @@ success:
vma->vm_flags = newflags;
if (lock) {
- /*
- * mmap_sem is currently held for write. Downgrade the write
- * lock to a read lock so that other faults, mmap scans, ...
- * while we fault in all pages.
- */
- downgrade_write(&mm->mmap_sem);
-
ret = __mlock_vma_pages_range(vma, start, end, 1);
- /*
- * Need to reacquire mmap sem in write mode, as our callers
- * expect this. We have no support for atomically upgrading
- * a sem to write, so we need to check for ranges while sem
- * is unlocked.
- */
- up_read(&mm->mmap_sem);
- /* vma can change or disappear */
- down_write(&mm->mmap_sem);
- *prev = find_vma(mm, start);
- /* non-NULL *prev must contain @start, but need to check @end */
- if (!(*prev) || end > (*prev)->vm_end)
- ret = -ENOMEM;
- else if (ret > 0) {
+ if (ret > 0) {
mm->locked_vm -= ret;
ret = 0;
} else
ret = __mlock_posix_error_return(ret); /* translate if needed */
} else {
- /*
- * TODO: for unlocking, pages will already be resident, so
- * we don't need to wait for allocations/reclaim/pagein, ...
- * However, unlocking a very large region can still take a
- * while. Should we downgrade the semaphore for both lock
- * AND unlock ?
- */
__mlock_vma_pages_range(vma, start, end, 0);
}
diff --git a/mm/mmap.c b/mm/mmap.c
index c581df14d0d..214b6a258ee 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1090,6 +1090,15 @@ int vma_wants_writenotify(struct vm_area_struct *vma)
mapping_cap_account_dirty(vma->vm_file->f_mapping);
}
+/*
+ * We account for memory if it's a private writeable mapping,
+ * and VM_NORESERVE wasn't set.
+ */
+static inline int accountable_mapping(unsigned int vm_flags)
+{
+ return (vm_flags & (VM_NORESERVE | VM_SHARED | VM_WRITE)) == VM_WRITE;
+}
+
unsigned long mmap_region(struct file *file, unsigned long addr,
unsigned long len, unsigned long flags,
unsigned int vm_flags, unsigned long pgoff,
@@ -1117,23 +1126,24 @@ munmap_back:
if (!may_expand_vm(mm, len >> PAGE_SHIFT))
return -ENOMEM;
- if (flags & MAP_NORESERVE)
+ /*
+ * Set 'VM_NORESERVE' if we should not account for the
+ * memory use of this mapping. We only honor MAP_NORESERVE
+ * if we're allowed to overcommit memory.
+ */
+ if ((flags & MAP_NORESERVE) && sysctl_overcommit_memory != OVERCOMMIT_NEVER)
+ vm_flags |= VM_NORESERVE;
+ if (!accountable)
vm_flags |= VM_NORESERVE;
- if (accountable && (!(flags & MAP_NORESERVE) ||
- sysctl_overcommit_memory == OVERCOMMIT_NEVER)) {
- if (vm_flags & VM_SHARED) {
- /* Check memory availability in shmem_file_setup? */
- vm_flags |= VM_ACCOUNT;
- } else if (vm_flags & VM_WRITE) {
- /*
- * Private writable mapping: check memory availability
- */
- charged = len >> PAGE_SHIFT;
- if (security_vm_enough_memory(charged))
- return -ENOMEM;
- vm_flags |= VM_ACCOUNT;
- }
+ /*
+ * Private writable mapping: check memory availability
+ */
+ if (accountable_mapping(vm_flags)) {
+ charged = len >> PAGE_SHIFT;
+ if (security_vm_enough_memory(charged))
+ return -ENOMEM;
+ vm_flags |= VM_ACCOUNT;
}
/*
@@ -1184,14 +1194,6 @@ munmap_back:
goto free_vma;
}
- /* We set VM_ACCOUNT in a shared mapping's vm_flags, to inform
- * shmem_zero_setup (perhaps called through /dev/zero's ->mmap)
- * that memory reservation must be checked; but that reservation
- * belongs to shared memory object, not to vma: so now clear it.
- */
- if ((vm_flags & (VM_SHARED|VM_ACCOUNT)) == (VM_SHARED|VM_ACCOUNT))
- vma->vm_flags &= ~VM_ACCOUNT;
-
/* Can addr have changed??
*
* Answer: Yes, several device drivers can do it in their
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index b493db7841d..dc32dae01e5 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -1051,13 +1051,22 @@ continue_unlock:
}
}
- if (wbc->sync_mode == WB_SYNC_NONE) {
- wbc->nr_to_write--;
- if (wbc->nr_to_write <= 0) {
- done = 1;
- break;
- }
+ if (nr_to_write > 0)
+ nr_to_write--;
+ else if (wbc->sync_mode == WB_SYNC_NONE) {
+ /*
+ * We stop writing back only if we are not
+ * doing integrity sync. In case of integrity
+ * sync we have to keep going because someone
+ * may be concurrently dirtying pages, and we
+ * might have synced a lot of newly appeared
+ * dirty pages, but have not synced all of the
+ * old dirty pages.
+ */
+ done = 1;
+ break;
}
+
if (wbc->nonblocking && bdi_write_congested(bdi)) {
wbc->encountered_congestion = 1;
done = 1;
diff --git a/mm/shmem.c b/mm/shmem.c
index 5d0de96c978..19d566ccdee 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2628,7 +2628,7 @@ struct file *shmem_file_setup(char *name, loff_t size, unsigned long flags)
goto close_file;
#ifdef CONFIG_SHMEM
- SHMEM_I(inode)->flags = flags & VM_ACCOUNT;
+ SHMEM_I(inode)->flags = (flags & VM_NORESERVE) ? 0 : VM_ACCOUNT;
#endif
d_instantiate(dentry, inode);
inode->i_size = size;
diff --git a/mm/slub.c b/mm/slub.c
index 6392ae5cc6b..bdc9abb08a2 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -1996,7 +1996,7 @@ static struct kmem_cache_cpu *alloc_kmem_cache_cpu(struct kmem_cache *s,
static void free_kmem_cache_cpu(struct kmem_cache_cpu *c, int cpu)
{
if (c < per_cpu(kmem_cache_cpu, cpu) ||
- c > per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) {
+ c >= per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) {
kfree(c);
return;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-03 21:04:14 +0000