mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 02:39:48 +00:00
Btrfs: Don't drop extent_map cache during releasepage on the btree inode
The btree inode should only have a single extent_map in the cache, it doesn't make sense to ever drop it. Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
parent
7ae9c09d8f
commit
7b13b7b119
3 changed files with 44 additions and 20 deletions
|
@ -76,13 +76,12 @@ struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
|
|||
struct extent_map *em;
|
||||
int ret;
|
||||
|
||||
again:
|
||||
spin_lock(&em_tree->lock);
|
||||
em = lookup_extent_mapping(em_tree, start, len);
|
||||
spin_unlock(&em_tree->lock);
|
||||
if (em) {
|
||||
if (em)
|
||||
goto out;
|
||||
}
|
||||
|
||||
em = alloc_extent_map(GFP_NOFS);
|
||||
if (!em) {
|
||||
em = ERR_PTR(-ENOMEM);
|
||||
|
@ -95,15 +94,21 @@ struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
|
|||
|
||||
spin_lock(&em_tree->lock);
|
||||
ret = add_extent_mapping(em_tree, em);
|
||||
spin_unlock(&em_tree->lock);
|
||||
|
||||
if (ret == -EEXIST) {
|
||||
free_extent_map(em);
|
||||
em = NULL;
|
||||
goto again;
|
||||
em = lookup_extent_mapping(em_tree, start, len);
|
||||
if (em)
|
||||
ret = 0;
|
||||
else
|
||||
ret = -EIO;
|
||||
} else if (ret) {
|
||||
em = ERR_PTR(ret);
|
||||
free_extent_map(em);
|
||||
em = NULL;
|
||||
}
|
||||
spin_unlock(&em_tree->lock);
|
||||
|
||||
if (ret)
|
||||
em = ERR_PTR(ret);
|
||||
out:
|
||||
return em;
|
||||
}
|
||||
|
@ -496,7 +501,7 @@ static int btree_releasepage(struct page *page, gfp_t gfp_flags)
|
|||
}
|
||||
tree = &BTRFS_I(page->mapping->host)->io_tree;
|
||||
map = &BTRFS_I(page->mapping->host)->extent_tree;
|
||||
ret = try_release_extent_mapping(map, tree, page, gfp_flags);
|
||||
ret = try_release_extent_state(map, tree, page, gfp_flags);
|
||||
if (ret == 1) {
|
||||
invalidate_extent_lru(tree, page_offset(page), PAGE_CACHE_SIZE);
|
||||
ClearPagePrivate(page);
|
||||
|
|
|
@ -2463,6 +2463,31 @@ int extent_prepare_write(struct extent_io_tree *tree,
|
|||
}
|
||||
EXPORT_SYMBOL(extent_prepare_write);
|
||||
|
||||
/*
|
||||
* a helper for releasepage, this tests for areas of the page that
|
||||
* are locked or under IO and drops the related state bits if it is safe
|
||||
* to drop the page.
|
||||
*/
|
||||
int try_release_extent_state(struct extent_map_tree *map,
|
||||
struct extent_io_tree *tree, struct page *page,
|
||||
gfp_t mask)
|
||||
{
|
||||
u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
|
||||
u64 end = start + PAGE_CACHE_SIZE - 1;
|
||||
int ret = 1;
|
||||
|
||||
if (test_range_bit(tree, start, end, EXTENT_IOBITS, 0))
|
||||
ret = 0;
|
||||
else {
|
||||
if ((mask & GFP_NOFS) == GFP_NOFS)
|
||||
mask = GFP_NOFS;
|
||||
clear_extent_bit(tree, start, end, EXTENT_UPTODATE,
|
||||
1, 1, mask);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(try_release_extent_state);
|
||||
|
||||
/*
|
||||
* a helper for releasepage. As long as there are no locked extents
|
||||
* in the range corresponding to the page, both state records and extent
|
||||
|
@ -2475,8 +2500,7 @@ int try_release_extent_mapping(struct extent_map_tree *map,
|
|||
struct extent_map *em;
|
||||
u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
|
||||
u64 end = start + PAGE_CACHE_SIZE - 1;
|
||||
u64 orig_start = start;
|
||||
int ret = 1;
|
||||
|
||||
if ((mask & __GFP_WAIT) &&
|
||||
page->mapping->host->i_size > 16 * 1024 * 1024) {
|
||||
u64 len;
|
||||
|
@ -2507,15 +2531,7 @@ int try_release_extent_mapping(struct extent_map_tree *map,
|
|||
free_extent_map(em);
|
||||
}
|
||||
}
|
||||
if (test_range_bit(tree, orig_start, end, EXTENT_IOBITS, 0))
|
||||
ret = 0;
|
||||
else {
|
||||
if ((mask & GFP_NOFS) == GFP_NOFS)
|
||||
mask = GFP_NOFS;
|
||||
clear_extent_bit(tree, orig_start, end, EXTENT_UPTODATE,
|
||||
1, 1, mask);
|
||||
}
|
||||
return ret;
|
||||
return try_release_extent_state(map, tree, page, mask);
|
||||
}
|
||||
EXPORT_SYMBOL(try_release_extent_mapping);
|
||||
|
||||
|
|
|
@ -110,6 +110,9 @@ void extent_io_tree_empty_lru(struct extent_io_tree *tree);
|
|||
int try_release_extent_mapping(struct extent_map_tree *map,
|
||||
struct extent_io_tree *tree, struct page *page,
|
||||
gfp_t mask);
|
||||
int try_release_extent_state(struct extent_map_tree *map,
|
||||
struct extent_io_tree *tree, struct page *page,
|
||||
gfp_t mask);
|
||||
int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
|
||||
int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask);
|
||||
int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
|
||||
|
|
Loading…
Reference in a new issue