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Diffstat (limited to 'mm/filemap.c')
-rw-r--r--mm/filemap.c69
1 files changed, 40 insertions, 29 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index 671f54c0d007..0e4b5dbf836f 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -467,32 +467,34 @@ int add_to_page_cache_locked(struct page *page, struct address_space *mapping,
error = mem_cgroup_cache_charge(page, current->mm,
gfp_mask & GFP_RECLAIM_MASK);
if (error)
- goto out;
+ return error;
error = radix_tree_maybe_preload(gfp_mask & ~__GFP_HIGHMEM);
- if (error == 0) {
- page_cache_get(page);
- page->mapping = mapping;
- page->index = offset;
-
- spin_lock_irq(&mapping->tree_lock);
- error = radix_tree_insert(&mapping->page_tree, offset, page);
- if (likely(!error)) {
- mapping->nrpages++;
- __inc_zone_page_state(page, NR_FILE_PAGES);
- spin_unlock_irq(&mapping->tree_lock);
- trace_mm_filemap_add_to_page_cache(page);
- } else {
- page->mapping = NULL;
- /* Leave page->index set: truncation relies upon it */
- spin_unlock_irq(&mapping->tree_lock);
- mem_cgroup_uncharge_cache_page(page);
- page_cache_release(page);
- }
- radix_tree_preload_end();
- } else
+ if (error) {
mem_cgroup_uncharge_cache_page(page);
-out:
+ return error;
+ }
+
+ page_cache_get(page);
+ page->mapping = mapping;
+ page->index = offset;
+
+ spin_lock_irq(&mapping->tree_lock);
+ error = radix_tree_insert(&mapping->page_tree, offset, page);
+ radix_tree_preload_end();
+ if (unlikely(error))
+ goto err_insert;
+ mapping->nrpages++;
+ __inc_zone_page_state(page, NR_FILE_PAGES);
+ spin_unlock_irq(&mapping->tree_lock);
+ trace_mm_filemap_add_to_page_cache(page);
+ return 0;
+err_insert:
+ page->mapping = NULL;
+ /* Leave page->index set: truncation relies upon it */
+ spin_unlock_irq(&mapping->tree_lock);
+ mem_cgroup_uncharge_cache_page(page);
+ page_cache_release(page);
return error;
}
EXPORT_SYMBOL(add_to_page_cache_locked);
@@ -1090,7 +1092,6 @@ static void shrink_readahead_size_eio(struct file *filp,
* @filp: the file to read
* @ppos: current file position
* @desc: read_descriptor
- * @actor: read method
*
* This is a generic file read routine, and uses the
* mapping->a_ops->readpage() function for the actual low-level stuff.
@@ -1099,7 +1100,7 @@ static void shrink_readahead_size_eio(struct file *filp,
* of the logic when it comes to error handling etc.
*/
static void do_generic_file_read(struct file *filp, loff_t *ppos,
- read_descriptor_t *desc, read_actor_t actor)
+ read_descriptor_t *desc)
{
struct address_space *mapping = filp->f_mapping;
struct inode *inode = mapping->host;
@@ -1200,13 +1201,14 @@ page_ok:
* Ok, we have the page, and it's up-to-date, so
* now we can copy it to user space...
*
- * The actor routine returns how many bytes were actually used..
+ * The file_read_actor routine returns how many bytes were
+ * actually used..
* NOTE! This may not be the same as how much of a user buffer
* we filled up (we may be padding etc), so we can only update
* "pos" here (the actor routine has to update the user buffer
* pointers and the remaining count).
*/
- ret = actor(desc, page, offset, nr);
+ ret = file_read_iter_actor(desc, page, offset, nr);
offset += ret;
index += offset >> PAGE_CACHE_SHIFT;
offset &= ~PAGE_CACHE_MASK;
@@ -1430,7 +1432,7 @@ generic_file_read_iter(struct kiocb *iocb, struct iov_iter *iter, loff_t pos)
desc.arg.data = iter;
desc.count = count;
desc.error = 0;
- do_generic_file_read(filp, ppos, &desc, file_read_iter_actor);
+ do_generic_file_read(filp, ppos, &desc);
if (desc.written)
retval = desc.written;
else
@@ -1592,6 +1594,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
struct inode *inode = mapping->host;
pgoff_t offset = vmf->pgoff;
struct page *page;
+ bool memcg_oom;
pgoff_t size;
int ret = 0;
@@ -1600,7 +1603,11 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
return VM_FAULT_SIGBUS;
/*
- * Do we have something in the page cache already?
+ * Do we have something in the page cache already? Either
+ * way, try readahead, but disable the memcg OOM killer for it
+ * as readahead is optional and no errors are propagated up
+ * the fault stack. The OOM killer is enabled while trying to
+ * instantiate the faulting page individually below.
*/
page = find_get_page(mapping, offset);
if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) {
@@ -1608,10 +1615,14 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
* We found the page, so try async readahead before
* waiting for the lock.
*/
+ memcg_oom = mem_cgroup_toggle_oom(false);
do_async_mmap_readahead(vma, ra, file, page, offset);
+ mem_cgroup_toggle_oom(memcg_oom);
} else if (!page) {
/* No page in the page cache at all */
+ memcg_oom = mem_cgroup_toggle_oom(false);
do_sync_mmap_readahead(vma, ra, file, offset);
+ mem_cgroup_toggle_oom(memcg_oom);
count_vm_event(PGMAJFAULT);
mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT);
ret = VM_FAULT_MAJOR;