In subpagesize-blocksize, we have multiple blocks in a page. Checking for
existence of a page in the page cache isn't a sufficient check, since we
could be truncating a subset of the blocks mapped by the page.
Signed-off-by: Chandan Rajendra <chan...@linux.vnet.ibm.com>
---
fs/btrfs/btrfs_inode.h | 2 --
fs/btrfs/file.c | 4 ++-
fs/btrfs/inode.c | 77 +++-----------------------------------------------
3 files changed, 7 insertions(+), 76 deletions(-)
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 43527fd..50497bf 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -278,6 +278,4 @@ static inline void btrfs_inode_resume_unlocked_dio(struct
inode *inode)
&BTRFS_I(inode)->runtime_flags);
}
-bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end);
-
#endif
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b1e0d27..3707515 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2314,7 +2314,9 @@ static int btrfs_punch_hole(struct inode *inode, loff_t
offset, loff_t len)
if ((!ordered ||
(ordered->file_offset + ordered->len <= lockstart ||
ordered->file_offset > lockend)) &&
- !btrfs_page_exists_in_range(inode, lockstart, lockend)) {
+ !test_range_bit(&BTRFS_I(inode)->io_tree, lockstart,
+ lockend, EXTENT_UPTODATE, 0,
+ cached_state)) {
if (ordered)
btrfs_put_ordered_extent(ordered);
break;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e0dd338..b236417 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6832,76 +6832,6 @@ out:
return ret;
}
-bool btrfs_page_exists_in_range(struct inode *inode, loff_t start, loff_t end)
-{
- struct radix_tree_root *root = &inode->i_mapping->page_tree;
- int found = false;
- void **pagep = NULL;
- struct page *page = NULL;
- int start_idx;
- int end_idx;
-
- start_idx = start >> PAGE_CACHE_SHIFT;
-
- /*
- * end is the last byte in the last page. end == start is legal
- */
- end_idx = end >> PAGE_CACHE_SHIFT;
-
- rcu_read_lock();
-
- /* Most of the code in this while loop is lifted from
- * find_get_page. It's been modified to begin searching from a
- * page and return just the first page found in that range. If the
- * found idx is less than or equal to the end idx then we know that
- * a page exists. If no pages are found or if those pages are
- * outside of the range then we're fine (yay!) */
- while (page == NULL &&
- radix_tree_gang_lookup_slot(root, &pagep, NULL, start_idx, 1)) {
- page = radix_tree_deref_slot(pagep);
- if (unlikely(!page))
- break;
-
- if (radix_tree_exception(page)) {
- if (radix_tree_deref_retry(page)) {
- page = NULL;
- continue;
- }
- /*
- * Otherwise, shmem/tmpfs must be storing a swap entry
- * here as an exceptional entry: so return it without
- * attempting to raise page count.
- */
- page = NULL;
- break; /* TODO: Is this relevant for this use case? */
- }
-
- if (!page_cache_get_speculative(page)) {
- page = NULL;
- continue;
- }
-
- /*
- * Has the page moved?
- * This is part of the lockless pagecache protocol. See
- * include/linux/pagemap.h for details.
- */
- if (unlikely(page != *pagep)) {
- page_cache_release(page);
- page = NULL;
- }
- }
-
- if (page) {
- if (page->index <= end_idx)
- found = true;
- page_cache_release(page);
- }
-
- rcu_read_unlock();
- return found;
-}
-
static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
struct extent_state **cached_state, int writing)
{
@@ -6926,9 +6856,10 @@ static int lock_extent_direct(struct inode *inode, u64
lockstart, u64 lockend,
* invalidate needs to happen so that reads after a write do not
* get stale data.
*/
- if (!ordered &&
- (!writing ||
- !btrfs_page_exists_in_range(inode, lockstart, lockend)))
+ if (!ordered && (!writing ||
+ !test_range_bit(&BTRFS_I(inode)->io_tree,
+ lockstart, lockend, EXTENT_UPTODATE, 0,
+ *cached_state)))
break;
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart,
lockend,
--
2.1.0
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