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Diffstat (limited to 'fs/btrfs/extent_io.c')
-rw-r--r--fs/btrfs/extent_io.c80
1 files changed, 61 insertions, 19 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2c8f7b204617..45c81bb4ac82 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -20,6 +20,7 @@
#include "volumes.h"
#include "check-integrity.h"
#include "locking.h"
+#include "rcu-string.h"
static struct kmem_cache *extent_state_cache;
static struct kmem_cache *extent_buffer_cache;
@@ -928,7 +929,8 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits,
/**
- * convert_extent - convert all bits in a given range from one bit to another
+ * convert_extent_bit - convert all bits in a given range from one bit to
+ * another
* @tree: the io tree to search
* @start: the start offset in bytes
* @end: the end offset in bytes (inclusive)
@@ -1917,9 +1919,9 @@ int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
return -EIO;
}
- printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s "
- "sector %llu)\n", page->mapping->host->i_ino, start,
- dev->name, sector);
+ printk_ratelimited_in_rcu(KERN_INFO "btrfs read error corrected: ino %lu off %llu "
+ "(dev %s sector %llu)\n", page->mapping->host->i_ino,
+ start, rcu_str_deref(dev->name), sector);
bio_put(bio);
return 0;
@@ -3076,8 +3078,15 @@ static int lock_extent_buffer_for_io(struct extent_buffer *eb,
}
}
+ /*
+ * We need to do this to prevent races in people who check if the eb is
+ * under IO since we can end up having no IO bits set for a short period
+ * of time.
+ */
+ spin_lock(&eb->refs_lock);
if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
set_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
+ spin_unlock(&eb->refs_lock);
btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
spin_lock(&fs_info->delalloc_lock);
if (fs_info->dirty_metadata_bytes >= eb->len)
@@ -3086,6 +3095,8 @@ static int lock_extent_buffer_for_io(struct extent_buffer *eb,
WARN_ON(1);
spin_unlock(&fs_info->delalloc_lock);
ret = 1;
+ } else {
+ spin_unlock(&eb->refs_lock);
}
btrfs_tree_unlock(eb);
@@ -3323,6 +3334,7 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
writepage_t writepage, void *data,
void (*flush_fn)(void *))
{
+ struct inode *inode = mapping->host;
int ret = 0;
int done = 0;
int nr_to_write_done = 0;
@@ -3333,6 +3345,18 @@ static int extent_write_cache_pages(struct extent_io_tree *tree,
int scanned = 0;
int tag;
+ /*
+ * We have to hold onto the inode so that ordered extents can do their
+ * work when the IO finishes. The alternative to this is failing to add
+ * an ordered extent if the igrab() fails there and that is a huge pain
+ * to deal with, so instead just hold onto the inode throughout the
+ * writepages operation. If it fails here we are freeing up the inode
+ * anyway and we'd rather not waste our time writing out stuff that is
+ * going to be truncated anyway.
+ */
+ if (!igrab(inode))
+ return 0;
+
pagevec_init(&pvec, 0);
if (wbc->range_cyclic) {
index = mapping->writeback_index; /* Start from prev offset */
@@ -3427,6 +3451,7 @@ retry:
index = 0;
goto retry;
}
+ btrfs_add_delayed_iput(inode);
return ret;
}
@@ -3542,19 +3567,38 @@ int extent_readpages(struct extent_io_tree *tree,
struct bio *bio = NULL;
unsigned page_idx;
unsigned long bio_flags = 0;
+ struct page *pagepool[16];
+ struct page *page;
+ int i = 0;
+ int nr = 0;
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
- struct page *page = list_entry(pages->prev, struct page, lru);
+ page = list_entry(pages->prev, struct page, lru);
prefetchw(&page->flags);
list_del(&page->lru);
- if (!add_to_page_cache_lru(page, mapping,
+ if (add_to_page_cache_lru(page, mapping,
page->index, GFP_NOFS)) {
- __extent_read_full_page(tree, page, get_extent,
- &bio, 0, &bio_flags);
+ page_cache_release(page);
+ continue;
}
- page_cache_release(page);
+
+ pagepool[nr++] = page;
+ if (nr < ARRAY_SIZE(pagepool))
+ continue;
+ for (i = 0; i < nr; i++) {
+ __extent_read_full_page(tree, pagepool[i], get_extent,
+ &bio, 0, &bio_flags);
+ page_cache_release(pagepool[i]);
+ }
+ nr = 0;
+ }
+ for (i = 0; i < nr; i++) {
+ __extent_read_full_page(tree, pagepool[i], get_extent,
+ &bio, 0, &bio_flags);
+ page_cache_release(pagepool[i]);
}
+
BUG_ON(!list_empty(pages));
if (bio)
return submit_one_bio(READ, bio, 0, bio_flags);
@@ -4108,11 +4152,10 @@ static void check_buffer_tree_ref(struct extent_buffer *eb)
* So bump the ref count first, then set the bit. If someone
* beat us to it, drop the ref we added.
*/
- if (!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) {
+ spin_lock(&eb->refs_lock);
+ if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
atomic_inc(&eb->refs);
- if (test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
- atomic_dec(&eb->refs);
- }
+ spin_unlock(&eb->refs_lock);
}
static void mark_extent_buffer_accessed(struct extent_buffer *eb)
@@ -4224,9 +4267,7 @@ again:
goto free_eb;
}
/* add one reference for the tree */
- spin_lock(&eb->refs_lock);
check_buffer_tree_ref(eb);
- spin_unlock(&eb->refs_lock);
spin_unlock(&tree->buffer_lock);
radix_tree_preload_end();
@@ -4285,7 +4326,7 @@ static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
}
/* Expects to have eb->eb_lock already held */
-static void release_extent_buffer(struct extent_buffer *eb, gfp_t mask)
+static int release_extent_buffer(struct extent_buffer *eb, gfp_t mask)
{
WARN_ON(atomic_read(&eb->refs) == 0);
if (atomic_dec_and_test(&eb->refs)) {
@@ -4306,9 +4347,11 @@ static void release_extent_buffer(struct extent_buffer *eb, gfp_t mask)
btrfs_release_extent_buffer_page(eb, 0);
call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
- return;
+ return 1;
}
spin_unlock(&eb->refs_lock);
+
+ return 0;
}
void free_extent_buffer(struct extent_buffer *eb)
@@ -4947,7 +4990,6 @@ int try_release_extent_buffer(struct page *page, gfp_t mask)
spin_unlock(&eb->refs_lock);
return 0;
}
- release_extent_buffer(eb, mask);
- return 1;
+ return release_extent_buffer(eb, mask);
}