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Diffstat (limited to 'fs/btrfs/extent_io.c')
-rw-r--r--fs/btrfs/extent_io.c1035
1 files changed, 734 insertions, 301 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2862454bcdb3..8d904dd7ea9f 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -19,6 +19,7 @@
#include "btrfs_inode.h"
#include "volumes.h"
#include "check-integrity.h"
+#include "locking.h"
static struct kmem_cache *extent_state_cache;
static struct kmem_cache *extent_buffer_cache;
@@ -53,6 +54,13 @@ struct extent_page_data {
unsigned int sync_io:1;
};
+static noinline void flush_write_bio(void *data);
+static inline struct btrfs_fs_info *
+tree_fs_info(struct extent_io_tree *tree)
+{
+ return btrfs_sb(tree->mapping->host->i_sb);
+}
+
int __init extent_io_init(void)
{
extent_state_cache = kmem_cache_create("extent_state",
@@ -136,6 +144,7 @@ static struct extent_state *alloc_extent_state(gfp_t mask)
#endif
atomic_set(&state->refs, 1);
init_waitqueue_head(&state->wq);
+ trace_alloc_extent_state(state, mask, _RET_IP_);
return state;
}
@@ -153,6 +162,7 @@ void free_extent_state(struct extent_state *state)
list_del(&state->leak_list);
spin_unlock_irqrestore(&leak_lock, flags);
#endif
+ trace_free_extent_state(state, _RET_IP_);
kmem_cache_free(extent_state_cache, state);
}
}
@@ -439,6 +449,13 @@ alloc_extent_state_atomic(struct extent_state *prealloc)
return prealloc;
}
+void extent_io_tree_panic(struct extent_io_tree *tree, int err)
+{
+ btrfs_panic(tree_fs_info(tree), err, "Locking error: "
+ "Extent tree was modified by another "
+ "thread while locked.");
+}
+
/*
* clear some bits on a range in the tree. This may require splitting
* or inserting elements in the tree, so the gfp mask is used to
@@ -449,8 +466,7 @@ alloc_extent_state_atomic(struct extent_state *prealloc)
*
* the range [start, end] is inclusive.
*
- * This takes the tree lock, and returns < 0 on error, > 0 if any of the
- * bits were already set, or zero if none of the bits were already set.
+ * This takes the tree lock, and returns 0 on success and < 0 on error.
*/
int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
int bits, int wake, int delete,
@@ -464,7 +480,6 @@ int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
struct rb_node *node;
u64 last_end;
int err;
- int set = 0;
int clear = 0;
if (delete)
@@ -542,12 +557,14 @@ hit_next:
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = split_state(tree, state, prealloc, start);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
+
prealloc = NULL;
if (err)
goto out;
if (state->end <= end) {
- set |= clear_state_bit(tree, state, &bits, wake);
+ clear_state_bit(tree, state, &bits, wake);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
@@ -564,17 +581,19 @@ hit_next:
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = split_state(tree, state, prealloc, end + 1);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
+
if (wake)
wake_up(&state->wq);
- set |= clear_state_bit(tree, prealloc, &bits, wake);
+ clear_state_bit(tree, prealloc, &bits, wake);
prealloc = NULL;
goto out;
}
- set |= clear_state_bit(tree, state, &bits, wake);
+ clear_state_bit(tree, state, &bits, wake);
next:
if (last_end == (u64)-1)
goto out;
@@ -591,7 +610,7 @@ out:
if (prealloc)
free_extent_state(prealloc);
- return set;
+ return 0;
search_again:
if (start > end)
@@ -602,8 +621,8 @@ search_again:
goto again;
}
-static int wait_on_state(struct extent_io_tree *tree,
- struct extent_state *state)
+static void wait_on_state(struct extent_io_tree *tree,
+ struct extent_state *state)
__releases(tree->lock)
__acquires(tree->lock)
{
@@ -613,7 +632,6 @@ static int wait_on_state(struct extent_io_tree *tree,
schedule();
spin_lock(&tree->lock);
finish_wait(&state->wq, &wait);
- return 0;
}
/*
@@ -621,7 +639,7 @@ static int wait_on_state(struct extent_io_tree *tree,
* The range [start, end] is inclusive.
* The tree lock is taken by this function
*/
-int wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits)
+void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits)
{
struct extent_state *state;
struct rb_node *node;
@@ -658,7 +676,6 @@ again:
}
out:
spin_unlock(&tree->lock);
- return 0;
}
static void set_state_bits(struct extent_io_tree *tree,
@@ -706,9 +723,10 @@ static void uncache_state(struct extent_state **cached_ptr)
* [start, end] is inclusive This takes the tree lock.
*/
-int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, int exclusive_bits, u64 *failed_start,
- struct extent_state **cached_state, gfp_t mask)
+static int __must_check
+__set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
+ int bits, int exclusive_bits, u64 *failed_start,
+ struct extent_state **cached_state, gfp_t mask)
{
struct extent_state *state;
struct extent_state *prealloc = NULL;
@@ -742,8 +760,10 @@ again:
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = insert_state(tree, prealloc, start, end, &bits);
+ if (err)
+ extent_io_tree_panic(tree, err);
+
prealloc = NULL;
- BUG_ON(err == -EEXIST);
goto out;
}
state = rb_entry(node, struct extent_state, rb_node);
@@ -809,7 +829,9 @@ hit_next:
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = split_state(tree, state, prealloc, start);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
+
prealloc = NULL;
if (err)
goto out;
@@ -846,12 +868,9 @@ hit_next:
*/
err = insert_state(tree, prealloc, start, this_end,
&bits);
- BUG_ON(err == -EEXIST);
- if (err) {
- free_extent_state(prealloc);
- prealloc = NULL;
- goto out;
- }
+ if (err)
+ extent_io_tree_panic(tree, err);
+
cache_state(prealloc, cached_state);
prealloc = NULL;
start = this_end + 1;
@@ -873,7 +892,8 @@ hit_next:
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = split_state(tree, state, prealloc, end + 1);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
set_state_bits(tree, prealloc, &bits);
cache_state(prealloc, cached_state);
@@ -900,6 +920,15 @@ search_again:
goto again;
}
+int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits,
+ u64 *failed_start, struct extent_state **cached_state,
+ gfp_t mask)
+{
+ return __set_extent_bit(tree, start, end, bits, 0, failed_start,
+ cached_state, mask);
+}
+
+
/**
* convert_extent - convert all bits in a given range from one bit to another
* @tree: the io tree to search
@@ -946,7 +975,8 @@ again:
}
err = insert_state(tree, prealloc, start, end, &bits);
prealloc = NULL;
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
goto out;
}
state = rb_entry(node, struct extent_state, rb_node);
@@ -1002,7 +1032,8 @@ hit_next:
goto out;
}
err = split_state(tree, state, prealloc, start);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
prealloc = NULL;
if (err)
goto out;
@@ -1041,12 +1072,8 @@ hit_next:
*/
err = insert_state(tree, prealloc, start, this_end,
&bits);
- BUG_ON(err == -EEXIST);
- if (err) {
- free_extent_state(prealloc);
- prealloc = NULL;
- goto out;
- }
+ if (err)
+ extent_io_tree_panic(tree, err);
prealloc = NULL;
start = this_end + 1;
goto search_again;
@@ -1065,7 +1092,8 @@ hit_next:
}
err = split_state(tree, state, prealloc, end + 1);
- BUG_ON(err == -EEXIST);
+ if (err)
+ extent_io_tree_panic(tree, err);
set_state_bits(tree, prealloc, &bits);
clear_state_bit(tree, prealloc, &clear_bits, 0);
@@ -1095,14 +1123,14 @@ search_again:
int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
gfp_t mask)
{
- return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL,
+ return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
NULL, mask);
}
int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
int bits, gfp_t mask)
{
- return set_extent_bit(tree, start, end, bits, 0, NULL,
+ return set_extent_bit(tree, start, end, bits, NULL,
NULL, mask);
}
@@ -1117,7 +1145,7 @@ int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
{
return set_extent_bit(tree, start, end,
EXTENT_DELALLOC | EXTENT_UPTODATE,
- 0, NULL, cached_state, mask);
+ NULL, cached_state, mask);
}
int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
@@ -1131,7 +1159,7 @@ int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
gfp_t mask)
{
- return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL,
+ return set_extent_bit(tree, start, end, EXTENT_NEW, NULL,
NULL, mask);
}
@@ -1139,7 +1167,7 @@ int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
struct extent_state **cached_state, gfp_t mask)
{
return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0,
- NULL, cached_state, mask);
+ cached_state, mask);
}
static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
@@ -1155,42 +1183,40 @@ static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
* us if waiting is desired.
*/
int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, struct extent_state **cached_state, gfp_t mask)
+ int bits, struct extent_state **cached_state)
{
int err;
u64 failed_start;
while (1) {
- err = set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
- EXTENT_LOCKED, &failed_start,
- cached_state, mask);
- if (err == -EEXIST && (mask & __GFP_WAIT)) {
+ err = __set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
+ EXTENT_LOCKED, &failed_start,
+ cached_state, GFP_NOFS);
+ if (err == -EEXIST) {
wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
start = failed_start;
- } else {
+ } else
break;
- }
WARN_ON(start > end);
}
return err;
}
-int lock_extent(struct extent_io_tree *tree, u64 start, u64 end, gfp_t mask)
+int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
{
- return lock_extent_bits(tree, start, end, 0, NULL, mask);
+ return lock_extent_bits(tree, start, end, 0, NULL);
}
-int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end,
- gfp_t mask)
+int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
{
int err;
u64 failed_start;
- err = set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
- &failed_start, NULL, mask);
+ err = __set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
+ &failed_start, NULL, GFP_NOFS);
if (err == -EEXIST) {
if (failed_start > start)
clear_extent_bit(tree, start, failed_start - 1,
- EXTENT_LOCKED, 1, 0, NULL, mask);
+ EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS);
return 0;
}
return 1;
@@ -1203,10 +1229,10 @@ int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
mask);
}
-int unlock_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)
{
return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
- mask);
+ GFP_NOFS);
}
/*
@@ -1220,7 +1246,7 @@ static int set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
while (index <= end_index) {
page = find_get_page(tree->mapping, index);
- BUG_ON(!page);
+ BUG_ON(!page); /* Pages should be in the extent_io_tree */
set_page_writeback(page);
page_cache_release(page);
index++;
@@ -1343,9 +1369,9 @@ out:
return found;
}
-static noinline int __unlock_for_delalloc(struct inode *inode,
- struct page *locked_page,
- u64 start, u64 end)
+static noinline void __unlock_for_delalloc(struct inode *inode,
+ struct page *locked_page,
+ u64 start, u64 end)
{
int ret;
struct page *pages[16];
@@ -1355,7 +1381,7 @@ static noinline int __unlock_for_delalloc(struct inode *inode,
int i;
if (index == locked_page->index && end_index == index)
- return 0;
+ return;
while (nr_pages > 0) {
ret = find_get_pages_contig(inode->i_mapping, index,
@@ -1370,7 +1396,6 @@ static noinline int __unlock_for_delalloc(struct inode *inode,
index += ret;
cond_resched();
}
- return 0;
}
static noinline int lock_delalloc_pages(struct inode *inode,
@@ -1500,11 +1525,10 @@ again:
goto out_failed;
}
}
- BUG_ON(ret);
+ BUG_ON(ret); /* Only valid values are 0 and -EAGAIN */
/* step three, lock the state bits for the whole range */
- lock_extent_bits(tree, delalloc_start, delalloc_end,
- 0, &cached_state, GFP_NOFS);
+ lock_extent_bits(tree, delalloc_start, delalloc_end, 0, &cached_state);
/* then test to make sure it is all still delalloc */
ret = test_range_bit(tree, delalloc_start, delalloc_end,
@@ -1761,39 +1785,34 @@ int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
* helper function to set a given page up to date if all the
* extents in the tree for that page are up to date
*/
-static int check_page_uptodate(struct extent_io_tree *tree,
- struct page *page)
+static void check_page_uptodate(struct extent_io_tree *tree, struct page *page)
{
u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
u64 end = start + PAGE_CACHE_SIZE - 1;
if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
SetPageUptodate(page);
- return 0;
}
/*
* helper function to unlock a page if all the extents in the tree
* for that page are unlocked
*/
-static int check_page_locked(struct extent_io_tree *tree,
- struct page *page)
+static void check_page_locked(struct extent_io_tree *tree, struct page *page)
{
u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
u64 end = start + PAGE_CACHE_SIZE - 1;
if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL))
unlock_page(page);
- return 0;
}
/*
* helper function to end page writeback if all the extents
* in the tree for that page are done with writeback
*/
-static int check_page_writeback(struct extent_io_tree *tree,
- struct page *page)
+static void check_page_writeback(struct extent_io_tree *tree,
+ struct page *page)
{
end_page_writeback(page);
- return 0;
}
/*
@@ -1912,6 +1931,26 @@ int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
return 0;
}
+int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
+ int mirror_num)
+{
+ struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
+ u64 start = eb->start;
+ unsigned long i, num_pages = num_extent_pages(eb->start, eb->len);
+ int ret;
+
+ for (i = 0; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+ ret = repair_io_failure(map_tree, start, PAGE_CACHE_SIZE,
+ start, p, mirror_num);
+ if (ret)
+ break;
+ start += PAGE_CACHE_SIZE;
+ }
+
+ return ret;
+}
+
/*
* each time an IO finishes, we do a fast check in the IO failure tree
* to see if we need to process or clean up an io_failure_record
@@ -2258,6 +2297,7 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
u64 start;
u64 end;
int whole_page;
+ int failed_mirror;
int ret;
if (err)
@@ -2304,9 +2344,16 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
else
clean_io_failure(start, page);
}
- if (!uptodate) {
- int failed_mirror;
+
+ if (!uptodate)
failed_mirror = (int)(unsigned long)bio->bi_bdev;
+
+ if (!uptodate && tree->ops && tree->ops->readpage_io_failed_hook) {
+ ret = tree->ops->readpage_io_failed_hook(page, failed_mirror);
+ if (!ret && !err &&
+ test_bit(BIO_UPTODATE, &bio->bi_flags))
+ uptodate = 1;
+ } else if (!uptodate) {
/*
* The generic bio_readpage_error handles errors the
* following way: If possible, new read requests are
@@ -2320,7 +2367,6 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
ret = bio_readpage_error(bio, page, start, end,
failed_mirror, NULL);
if (ret == 0) {
-error_handled:
uptodate =
test_bit(BIO_UPTODATE, &bio->bi_flags);
if (err)
@@ -2328,16 +2374,9 @@ error_handled:
uncache_state(&cached);
continue;
}
- if (tree->ops && tree->ops->readpage_io_failed_hook) {
- ret = tree->ops->readpage_io_failed_hook(
- bio, page, start, end,
- failed_mirror, state);
- if (ret == 0)
- goto error_handled;
- }
}
- if (uptodate) {
+ if (uptodate && tree->track_uptodate) {
set_extent_uptodate(tree, start, end, &cached,
GFP_ATOMIC);
}
@@ -2386,8 +2425,12 @@ btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
return bio;
}
-static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
- unsigned long bio_flags)
+/*
+ * Since writes are async, they will only return -ENOMEM.
+ * Reads can return the full range of I/O error conditions.
+ */
+static int __must_check submit_one_bio(int rw, struct bio *bio,
+ int mirror_num, unsigned long bio_flags)
{
int ret = 0;
struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
@@ -2413,6 +2456,19 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num,
return ret;
}
+static int merge_bio(struct extent_io_tree *tree, struct page *page,
+ unsigned long offset, size_t size, struct bio *bio,
+ unsigned long bio_flags)
+{
+ int ret = 0;
+ if (tree->ops && tree->ops->merge_bio_hook)
+ ret = tree->ops->merge_bio_hook(page, offset, size, bio,
+ bio_flags);
+ BUG_ON(ret < 0);
+ return ret;
+
+}
+
static int submit_extent_page(int rw, struct extent_io_tree *tree,
struct page *page, sector_t sector,
size_t size, unsigned long offset,
@@ -2441,12 +2497,12 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
sector;
if (prev_bio_flags != bio_flags || !contig ||
- (tree->ops && tree->ops->merge_bio_hook &&
- tree->ops->merge_bio_hook(page, offset, page_size, bio,
- bio_flags)) ||
+ merge_bio(tree, page, offset, page_size, bio, bio_flags) ||
bio_add_page(bio, page, page_size, offset) < page_size) {
ret = submit_one_bio(rw, bio, mirror_num,
prev_bio_flags);
+ if (ret < 0)
+ return ret;
bio = NULL;
} else {
return 0;
@@ -2473,25 +2529,31 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
return ret;
}
-void set_page_extent_mapped(struct page *page)
+void attach_extent_buffer_page(struct extent_buffer *eb, struct page *page)
{
if (!PagePrivate(page)) {
SetPagePrivate(page);
page_cache_get(page);
- set_page_private(page, EXTENT_PAGE_PRIVATE);
+ set_page_private(page, (unsigned long)eb);
+ } else {
+ WARN_ON(page->private != (unsigned long)eb);
}
}
-static void set_page_extent_head(struct page *page, unsigned long len)
+void set_page_extent_mapped(struct page *page)
{
- WARN_ON(!PagePrivate(page));
- set_page_private(page, EXTENT_PAGE_PRIVATE_FIRST_PAGE | len << 2);
+ if (!PagePrivate(page)) {
+ SetPagePrivate(page);
+ page_cache_get(page);
+ set_page_private(page, EXTENT_PAGE_PRIVATE);
+ }
}
/*
* basic readpage implementation. Locked extent state structs are inserted
* into the tree that are removed when the IO is done (by the end_io
* handlers)
+ * XXX JDM: This needs looking at to ensure proper page locking
*/
static int __extent_read_full_page(struct extent_io_tree *tree,
struct page *page,
@@ -2531,11 +2593,11 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
end = page_end;
while (1) {
- lock_extent(tree, start, end, GFP_NOFS);
+ lock_extent(tree, start, end);
ordered = btrfs_lookup_ordered_extent(inode, start);
if (!ordered)
break;
- unlock_extent(tree, start, end, GFP_NOFS);
+ unlock_extent(tree, start, end);
btrfs_start_ordered_extent(inode, ordered, 1);
btrfs_put_ordered_extent(ordered);
}
@@ -2572,7 +2634,7 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
end - cur + 1, 0);
if (IS_ERR_OR_NULL(em)) {
SetPageError(page);
- unlock_extent(tree, cur, end, GFP_NOFS);
+ unlock_extent(tree, cur, end);
break;
}
extent_offset = cur - em->start;
@@ -2624,7 +2686,7 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
if (test_range_bit(tree, cur, cur_end,
EXTENT_UPTODATE, 1, NULL)) {
check_page_uptodate(tree, page);
- unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
+ unlock_extent(tree, cur, cur + iosize - 1);
cur = cur + iosize;
pg_offset += iosize;
continue;
@@ -2634,7 +2696,7 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
*/
if (block_start == EXTENT_MAP_INLINE) {
SetPageError(page);
- unlock_extent(tree, cur, cur + iosize - 1, GFP_NOFS);
+ unlock_extent(tree, cur, cur + iosize - 1);
cur = cur + iosize;
pg_offset += iosize;
continue;
@@ -2654,6 +2716,7 @@ static int __extent_read_full_page(struct extent_io_tree *tree,
end_bio_extent_readpage, mirror_num,
*bio_flags,
this_bio_flag);
+ BUG_ON(ret == -ENOMEM);
nr++;
*bio_flags = this_bio_flag;
}
@@ -2795,7 +2858,11 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
delalloc_end,
&page_started,
&nr_written);
- BUG_ON(ret);
+ /* File system has been set read-only */
+ if (ret) {
+ SetPageError(page);
+ goto done;
+ }
/*
* delalloc_end is already one less than the total
* length, so we don't subtract one from
@@ -2968,6 +3035,275 @@ done_unlocked:
return 0;
}
+static int eb_wait(void *word)
+{
+ io_schedule();
+ return 0;
+}
+
+static void wait_on_extent_buffer_writeback(struct extent_buffer *eb)
+{
+ wait_on_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK, eb_wait,
+ TASK_UNINTERRUPTIBLE);
+}
+
+static int lock_extent_buffer_for_io(struct extent_buffer *eb,
+ struct btrfs_fs_info *fs_info,
+ struct extent_page_data *epd)
+{
+ unsigned long i, num_pages;
+ int flush = 0;
+ int ret = 0;
+
+ if (!btrfs_try_tree_write_lock(eb)) {
+ flush = 1;
+ flush_write_bio(epd);
+ btrfs_tree_lock(eb);
+ }
+
+ if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags)) {
+ btrfs_tree_unlock(eb);
+ if (!epd->sync_io)
+ return 0;
+ if (!flush) {
+ flush_write_bio(epd);
+ flush = 1;
+ }
+ while (1) {
+ wait_on_extent_buffer_writeback(eb);
+ btrfs_tree_lock(eb);
+ if (!test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags))
+ break;
+ btrfs_tree_unlock(eb);
+ }
+ }
+
+ if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
+ set_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
+ btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
+ spin_lock(&fs_info->delalloc_lock);
+ if (fs_info->dirty_metadata_bytes >= eb->len)
+ fs_info->dirty_metadata_bytes -= eb->len;
+ else
+ WARN_ON(1);
+ spin_unlock(&fs_info->delalloc_lock);
+ ret = 1;
+ }
+
+ btrfs_tree_unlock(eb);
+
+ if (!ret)
+ return ret;
+
+ num_pages = num_extent_pages(eb->start, eb->len);
+ for (i = 0; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+
+ if (!trylock_page(p)) {
+ if (!flush) {
+ flush_write_bio(epd);
+ flush = 1;
+ }
+ lock_page(p);
+ }
+ }
+
+ return ret;
+}
+
+static void end_extent_buffer_writeback(struct extent_buffer *eb)
+{
+ clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
+ smp_mb__after_clear_bit();
+ wake_up_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK);
+}
+
+static void end_bio_extent_buffer_writepage(struct bio *bio, int err)
+{
+ int uptodate = err == 0;
+ struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
+ struct extent_buffer *eb;
+ int done;
+
+ do {
+ struct page *page = bvec->bv_page;
+
+ bvec--;
+ eb = (struct extent_buffer *)page->private;
+ BUG_ON(!eb);
+ done = atomic_dec_and_test(&eb->io_pages);
+
+ if (!uptodate || test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
+ set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+ ClearPageUptodate(page);
+ SetPageError(page);
+ }
+
+ end_page_writeback(page);
+
+ if (!done)
+ continue;
+
+ end_extent_buffer_writeback(eb);
+ } while (bvec >= bio->bi_io_vec);
+
+ bio_put(bio);
+
+}
+
+static int write_one_eb(struct extent_buffer *eb,
+ struct btrfs_fs_info *fs_info,
+ struct writeback_control *wbc,
+ struct extent_page_data *epd)
+{
+ struct block_device *bdev = fs_info->fs_devices->latest_bdev;
+ u64 offset = eb->start;
+ unsigned long i, num_pages;
+ int rw = (epd->sync_io ? WRITE_SYNC : WRITE);
+ int ret;
+
+ clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+ num_pages = num_extent_pages(eb->start, eb->len);
+ atomic_set(&eb->io_pages, num_pages);
+ for (i = 0; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+
+ clear_page_dirty_for_io(p);
+ set_page_writeback(p);
+ ret = submit_extent_page(rw, eb->tree, p, offset >> 9,
+ PAGE_CACHE_SIZE, 0, bdev, &epd->bio,
+ -1, end_bio_extent_buffer_writepage,
+ 0, 0, 0);
+ if (ret) {
+ set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+ SetPageError(p);
+ if (atomic_sub_and_test(num_pages - i, &eb->io_pages))
+ end_extent_buffer_writeback(eb);
+ ret = -EIO;
+ break;
+ }
+ offset += PAGE_CACHE_SIZE;
+ update_nr_written(p, wbc, 1);
+ unlock_page(p);
+ }
+
+ if (unlikely(ret)) {
+ for (; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+ unlock_page(p);
+ }
+ }
+
+ return ret;
+}
+
+int btree_write_cache_pages(struct address_space *mapping,
+ struct writeback_control *wbc)
+{
+ struct extent_io_tree *tree = &BTRFS_I(mapping->host)->io_tree;
+ struct btrfs_fs_info *fs_info = BTRFS_I(mapping->host)->root->fs_info;
+ struct extent_buffer *eb, *prev_eb = NULL;
+ struct extent_page_data epd = {
+ .bio = NULL,
+ .tree = tree,
+ .extent_locked = 0,
+ .sync_io = wbc->sync_mode == WB_SYNC_ALL,
+ };
+ int ret = 0;
+ int done = 0;
+ int nr_to_write_done = 0;
+ struct pagevec pvec;
+ int nr_pages;
+ pgoff_t index;
+ pgoff_t end; /* Inclusive */
+ int scanned = 0;
+ int tag;
+
+ pagevec_init(&pvec, 0);
+ if (wbc->range_cyclic) {
+ index = mapping->writeback_index; /* Start from prev offset */
+ end = -1;
+ } else {
+ index = wbc->range_start >> PAGE_CACHE_SHIFT;
+ end = wbc->range_end >> PAGE_CACHE_SHIFT;
+ scanned = 1;
+ }
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ tag = PAGECACHE_TAG_TOWRITE;
+ else
+ tag = PAGECACHE_TAG_DIRTY;
+retry:
+ if (wbc->sync_mode == WB_SYNC_ALL)
+ tag_pages_for_writeback(mapping, index, end);
+ while (!done && !nr_to_write_done && (index <= end) &&
+ (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
+ min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
+ unsigned i;
+
+ scanned = 1;
+ for (i = 0; i < nr_pages; i++) {
+ struct page *page = pvec.pages[i];
+
+ if (!PagePrivate(page))
+ continue;
+
+ if (!wbc->range_cyclic && page->index > end) {
+ done = 1;
+ break;
+ }
+
+ eb = (struct extent_buffer *)page->private;
+ if (!eb) {
+ WARN_ON(1);
+ continue;
+ }
+
+ if (eb == prev_eb)
+ continue;
+
+ if (!atomic_inc_not_zero(&eb->refs)) {
+ WARN_ON(1);
+ continue;
+ }
+
+ prev_eb = eb;
+ ret = lock_extent_buffer_for_io(eb, fs_info, &epd);
+ if (!ret) {
+ free_extent_buffer(eb);
+ continue;
+ }
+
+ ret = write_one_eb(eb, fs_info, wbc, &epd);
+ if (ret) {
+ done = 1;
+ free_extent_buffer(eb);
+ break;
+ }
+ free_extent_buffer(eb);
+
+ /*
+ * the filesystem may choose to bump up nr_to_write.
+ * We have to make sure to honor the new nr_to_write
+ * at any time
+ */
+ nr_to_write_done = wbc->nr_to_write <= 0;
+ }
+ pagevec_release(&pvec);
+ cond_resched();
+ }
+ if (!scanned && !done) {
+ /*
+ * We hit the last page and there is more work to be done: wrap
+ * back to the start of the file
+ */
+ scanned = 1;
+ index = 0;
+ goto retry;
+ }
+ flush_write_bio(&epd);
+ return ret;
+}
+
/**
* write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
* @mapping: address space structure to write
@@ -3099,10 +3435,14 @@ retry:
static void flush_epd_write_bio(struct extent_page_data *epd)
{
if (epd->bio) {
+ int rw = WRITE;
+ int ret;
+
if (epd->sync_io)
- submit_one_bio(WRITE_SYNC, epd->bio, 0, 0);
- else
- submit_one_bio(WRITE, epd->bio, 0, 0);
+ rw = WRITE_SYNC;
+
+ ret = submit_one_bio(rw, epd->bio, 0, 0);
+ BUG_ON(ret < 0); /* -ENOMEM */
epd->bio = NULL;
}
}
@@ -3219,7 +3559,7 @@ int extent_readpages(struct extent_io_tree *tree,
}
BUG_ON(!list_empty(pages));
if (bio)
- submit_one_bio(READ, bio, 0, bio_flags);
+ return submit_one_bio(READ, bio, 0, bio_flags);
return 0;
}
@@ -3240,7 +3580,7 @@ int extent_invalidatepage(struct extent_io_tree *tree,
if (start > end)
return 0;
- lock_extent_bits(tree, start, end, 0, &cached_state, GFP_NOFS);
+ lock_extent_bits(tree, start, end, 0, &cached_state);
wait_on_page_writeback(page);
clear_extent_bit(tree, start, end,
EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
@@ -3454,7 +3794,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
}
lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0,
- &cached_state, GFP_NOFS);
+ &cached_state);
em = get_extent_skip_holes(inode, start, last_for_get_extent,
get_extent);
@@ -3548,26 +3888,7 @@ out:
inline struct page *extent_buffer_page(struct extent_buffer *eb,
unsigned long i)
{
- struct page *p;
- struct address_space *mapping;
-
- if (i == 0)
- return eb->first_page;
- i += eb->start >> PAGE_CACHE_SHIFT;
- mapping = eb->first_page->mapping;
- if (!mapping)
- return NULL;
-
- /*
- * extent_buffer_page is only called after pinning the page
- * by increasing the reference count. So we know the page must
- * be in the radix tree.
- */
- rcu_read_lock();
- p = radix_tree_lookup(&mapping->page_tree, i);
- rcu_read_unlock();
-
- return p;
+ return eb->pages[i];
}
inline unsigned long num_extent_pages(u64 start, u64 len)
@@ -3576,6 +3897,19 @@ inline unsigned long num_extent_pages(u64 start, u64 len)
(start >> PAGE_CACHE_SHIFT);
}
+static void __free_extent_buffer(struct extent_buffer *eb)
+{
+#if LEAK_DEBUG
+ unsigned long flags;
+ spin_lock_irqsave(&leak_lock, flags);
+ list_del(&eb->leak_list);
+ spin_unlock_irqrestore(&leak_lock, flags);
+#endif
+ if (eb->pages && eb->pages != eb->inline_pages)
+ kfree(eb->pages);
+ kmem_cache_free(extent_buffer_cache, eb);
+}
+
static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
u64 start,
unsigned long len,
@@ -3591,6 +3925,7 @@ static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
return NULL;
eb->start = start;
eb->len = len;
+ eb->tree = tree;
rwlock_init(&eb->lock);
atomic_set(&eb->write_locks, 0);
atomic_set(&eb->read_locks, 0);
@@ -3607,20 +3942,32 @@ static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
list_add(&eb->leak_list, &buffers);
spin_unlock_irqrestore(&leak_lock, flags);
#endif
+ spin_lock_init(&eb->refs_lock);
atomic_set(&eb->refs, 1);
+ atomic_set(&eb->io_pages, 0);
+
+ if (len > MAX_INLINE_EXTENT_BUFFER_SIZE) {
+ struct page **pages;
+ int num_pages = (len + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT;
+ pages = kzalloc(num_pages, mask);
+ if (!pages) {
+ __free_extent_buffer(eb);
+ return NULL;
+ }
+ eb->pages = pages;
+ } else {
+ eb->pages = eb->inline_pages;
+ }
return eb;
}
-static void __free_extent_buffer(struct extent_buffer *eb)
+static int extent_buffer_under_io(struct extent_buffer *eb)
{
-#if LEAK_DEBUG
- unsigned long flags;
- spin_lock_irqsave(&leak_lock, flags);
- list_del(&eb->leak_list);
- spin_unlock_irqrestore(&leak_lock, flags);
-#endif
- kmem_cache_free(extent_buffer_cache, eb);
+ return (atomic_read(&eb->io_pages) ||
+ test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags) ||
+ test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
}
/*
@@ -3632,8 +3979,7 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
unsigned long index;
struct page *page;
- if (!eb->first_page)
- return;
+ BUG_ON(extent_buffer_under_io(eb));
index = num_extent_pages(eb->start, eb->len);
if (start_idx >= index)
@@ -3642,8 +3988,34 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
do {
index--;
page = extent_buffer_page(eb, index);
- if (page)
+ if (page) {
+ spin_lock(&page->mapping->private_lock);
+ /*
+ * We do this since we'll remove the pages after we've
+ * removed the eb from the radix tree, so we could race
+ * and have this page now attached to the new eb. So
+ * only clear page_private if it's still connected to
+ * this eb.
+ */
+ if (PagePrivate(page) &&
+ page->private == (unsigned long)eb) {
+ BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+ BUG_ON(PageDirty(page));
+ BUG_ON(PageWriteback(page));
+ /*
+ * We need to make sure we haven't be attached
+ * to a new eb.
+ */
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ /* One for the page private */
+ page_cache_release(page);
+ }
+ spin_unlock(&page->mapping->private_lock);
+
+ /* One for when we alloced the page */
page_cache_release(page);
+ }
} while (index != start_idx);
}
@@ -3656,9 +4028,50 @@ static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
__free_extent_buffer(eb);
}
+static void check_buffer_tree_ref(struct extent_buffer *eb)
+{
+ /* the ref bit is tricky. We have to make sure it is set
+ * if we have the buffer dirty. Otherwise the
+ * code to free a buffer can end up dropping a dirty
+ * page
+ *
+ * Once the ref bit is set, it won't go away while the
+ * buffer is dirty or in writeback, and it also won't
+ * go away while we have the reference count on the
+ * eb bumped.
+ *
+ * We can't just set the ref bit without bumping the
+ * ref on the eb because free_extent_buffer might
+ * see the ref bit and try to clear it. If this happens
+ * free_extent_buffer might end up dropping our original
+ * ref by mistake and freeing the page before we are able
+ * to add one more ref.
+ *
+ * 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)) {
+ atomic_inc(&eb->refs);
+ if (test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
+ atomic_dec(&eb->refs);
+ }
+}
+
+static void mark_extent_buffer_accessed(struct extent_buffer *eb)
+{
+ unsigned long num_pages, i;
+
+ check_buffer_tree_ref(eb);
+
+ num_pages = num_extent_pages(eb->start, eb->len);
+ for (i = 0; i < num_pages; i++) {
+ struct page *p = extent_buffer_page(eb, i);
+ mark_page_accessed(p);
+ }
+}
+
struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
- u64 start, unsigned long len,
- struct page *page0)
+ u64 start, unsigned long len)
{
unsigned long num_pages = num_extent_pages(start, len);
unsigned long i;
@@ -3674,7 +4087,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
if (eb && atomic_inc_not_zero(&eb->refs)) {
rcu_read_unlock();
- mark_page_accessed(eb->first_page);
+ mark_extent_buffer_accessed(eb);
return eb;
}
rcu_read_unlock();
@@ -3683,32 +4096,43 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
if (!eb)
return NULL;
- if (page0) {
- eb->first_page = page0;
- i = 1;
- index++;
- page_cache_get(page0);
- mark_page_accessed(page0);
- set_page_extent_mapped(page0);
- set_page_extent_head(page0, len);
- uptodate = PageUptodate(page0);
- } else {
- i = 0;
- }
- for (; i < num_pages; i++, index++) {
+ for (i = 0; i < num_pages; i++, index++) {
p = find_or_create_page(mapping, index, GFP_NOFS);
if (!p) {
WARN_ON(1);
goto free_eb;
}
- set_page_extent_mapped(p);
- mark_page_accessed(p);
- if (i == 0) {
- eb->first_page = p;
- set_page_extent_head(p, len);
- } else {
- set_page_private(p, EXTENT_PAGE_PRIVATE);
+
+ spin_lock(&mapping->private_lock);
+ if (PagePrivate(p)) {
+ /*
+ * We could have already allocated an eb for this page
+ * and attached one so lets see if we can get a ref on
+ * the existing eb, and if we can we know it's good and
+ * we can just return that one, else we know we can just
+ * overwrite page->private.
+ */
+ exists = (struct extent_buffer *)p->private;
+ if (atomic_inc_not_zero(&exists->refs)) {
+ spin_unlock(&mapping->private_lock);
+ unlock_page(p);
+ mark_extent_buffer_accessed(exists);
+ goto free_eb;
+ }
+
+ /*
+ * Do this so attach doesn't complain and we need to
+ * drop the ref the old guy had.
+ */
+ ClearPagePrivate(p);
+ WARN_ON(PageDirty(p));
+ page_cache_release(p);
}
+ attach_extent_buffer_page(eb, p);
+ spin_unlock(&mapping->private_lock);
+ WARN_ON(PageDirty(p));
+ mark_page_accessed(p);
+ eb->pages[i] = p;
if (!PageUptodate(p))
uptodate = 0;
@@ -3716,12 +4140,10 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
* see below about how we avoid a nasty race with release page
* and why we unlock later
*/
- if (i != 0)
- unlock_page(p);
}
if (uptodate)
set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
-
+again:
ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
if (ret)
goto free_eb;
@@ -3731,14 +4153,21 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
if (ret == -EEXIST) {
exists = radix_tree_lookup(&tree->buffer,
start >> PAGE_CACHE_SHIFT);
- /* add one reference for the caller */
- atomic_inc(&exists->refs);
+ if (!atomic_inc_not_zero(&exists->refs)) {
+ spin_unlock(&tree->buffer_lock);
+ radix_tree_preload_end();
+ exists = NULL;
+ goto again;
+ }
spin_unlock(&tree->buffer_lock);
radix_tree_preload_end();
+ mark_extent_buffer_accessed(exists);
goto free_eb;
}
/* add one reference for the tree */
- atomic_inc(&eb->refs);
+ spin_lock(&eb->refs_lock);
+ check_buffer_tree_ref(eb);
+ spin_unlock(&eb->refs_lock);
spin_unlock(&tree->buffer_lock);
radix_tree_preload_end();
@@ -3751,15 +4180,20 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
* after the extent buffer is in the radix tree so
* it doesn't get lost
*/
- set_page_extent_mapped(eb->first_page);
- set_page_extent_head(eb->first_page, eb->len);
- if (!page0)
- unlock_page(eb->first_page);
+ SetPageChecked(eb->pages[0]);
+ for (i = 1; i < num_pages; i++) {
+ p = extent_buffer_page(eb, i);
+ ClearPageChecked(p);
+ unlock_page(p);
+ }
+ unlock_page(eb->pages[0]);
return eb;
free_eb:
- if (eb->first_page && !page0)
- unlock_page(eb->first_page);
+ for (i = 0; i < num_pages; i++) {
+ if (eb->pages[i])
+ unlock_page(eb->pages[i]);
+ }
if (!atomic_dec_and_test(&eb->refs))
return exists;
@@ -3776,7 +4210,7 @@ struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
if (eb && atomic_inc_not_zero(&eb->refs)) {
rcu_read_unlock();
- mark_page_accessed(eb->first_page);
+ mark_extent_buffer_accessed(eb);
return eb;
}
rcu_read_unlock();
@@ -3784,19 +4218,71 @@ struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
return NULL;
}
+static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
+{
+ struct extent_buffer *eb =
+ container_of(head, struct extent_buffer, rcu_head);
+
+ __free_extent_buffer(eb);
+}
+
+/* Expects to have eb->eb_lock already held */
+static void release_extent_buffer(struct extent_buffer *eb, gfp_t mask)
+{
+ WARN_ON(atomic_read(&eb->refs) == 0);
+ if (atomic_dec_and_test(&eb->refs)) {
+ struct extent_io_tree *tree = eb->tree;
+
+ spin_unlock(&eb->refs_lock);
+
+ spin_lock(&tree->buffer_lock);
+ radix_tree_delete(&tree->buffer,
+ eb->start >> PAGE_CACHE_SHIFT);
+ spin_unlock(&tree->buffer_lock);
+
+ /* Should be safe to release our pages at this point */
+ btrfs_release_extent_buffer_page(eb, 0);
+
+ call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
+ return;
+ }
+ spin_unlock(&eb->refs_lock);
+}
+
void free_extent_buffer(struct extent_buffer *eb)
{
if (!eb)
return;
- if (!atomic_dec_and_test(&eb->refs))
+ spin_lock(&eb->refs_lock);
+ if (atomic_read(&eb->refs) == 2 &&
+ test_bit(EXTENT_BUFFER_STALE, &eb->bflags) &&
+ !extent_buffer_under_io(eb) &&
+ test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
+ atomic_dec(&eb->refs);
+
+ /*
+ * I know this is terrible, but it's temporary until we stop tracking
+ * the uptodate bits and such for the extent buffers.
+ */
+ release_extent_buffer(eb, GFP_ATOMIC);
+}
+
+void free_extent_buffer_stale(struct extent_buffer *eb)
+{
+ if (!eb)
return;
- WARN_ON(1);
+ spin_lock(&eb->refs_lock);
+ set_bit(EXTENT_BUFFER_STALE, &eb->bflags);
+
+ if (atomic_read(&eb->refs) == 2 && !extent_buffer_under_io(eb) &&
+ test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
+ atomic_dec(&eb->refs);
+ release_extent_buffer(eb, GFP_NOFS);
}
-int clear_extent_buffer_dirty(struct extent_io_tree *tree,
- struct extent_buffer *eb)
+void clear_extent_buffer_dirty(struct extent_buffer *eb)
{
unsigned long i;
unsigned long num_pages;
@@ -3812,10 +4298,6 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
lock_page(page);
WARN_ON(!PagePrivate(page));
- set_page_extent_mapped(page);
- if (i == 0)
- set_page_extent_head(page, eb->len);
-
clear_page_dirty_for_io(page);
spin_lock_irq(&page->mapping->tree_lock);
if (!PageDirty(page)) {
@@ -3827,24 +4309,29 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
ClearPageError(page);
unlock_page(page);
}
- return 0;
+ WARN_ON(atomic_read(&eb->refs) == 0);
}
-int set_extent_buffer_dirty(struct extent_io_tree *tree,
- struct extent_buffer *eb)
+int set_extent_buffer_dirty(struct extent_buffer *eb)
{
unsigned long i;
unsigned long num_pages;
int was_dirty = 0;
+ check_buffer_tree_ref(eb);
+
was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
+
num_pages = num_extent_pages(eb->start, eb->len);
+ WARN_ON(atomic_read(&eb->refs) == 0);
+ WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags));
+
for (i = 0; i < num_pages; i++)
- __set_page_dirty_nobuffers(extent_buffer_page(eb, i));
+ set_page_dirty(extent_buffer_page(eb, i));
return was_dirty;
}
-static int __eb_straddles_pages(u64 start, u64 len)
+static int range_straddles_pages(u64 start, u64 len)
{
if (len < PAGE_CACHE_SIZE)
return 1;
@@ -3855,25 +4342,14 @@ static int __eb_straddles_pages(u64 start, u64 len)
return 0;
}
-static int eb_straddles_pages(struct extent_buffer *eb)
-{
- return __eb_straddles_pages(eb->start, eb->len);
-}
-
-int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
- struct extent_buffer *eb,
- struct extent_state **cached_state)
+int clear_extent_buffer_uptodate(struct extent_buffer *eb)
{
unsigned long i;
struct page *page;
unsigned long num_pages;
- num_pages = num_extent_pages(eb->start, eb->len);
clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
-
- clear_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
- cached_state, GFP_NOFS);
-
+ num_pages = num_extent_pages(eb->start, eb->len);
for (i = 0; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
if (page)
@@ -3882,27 +4358,16 @@ int clear_extent_buffer_uptodate(struct extent_io_tree *tree,
return 0;
}
-int set_extent_buffer_uptodate(struct extent_io_tree *tree,
- struct extent_buffer *eb)
+int set_extent_buffer_uptodate(struct extent_buffer *eb)
{
unsigned long i;
struct page *page;
unsigned long num_pages;
+ set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
num_pages = num_extent_pages(eb->start, eb->len);
-
- if (eb_straddles_pages(eb)) {
- set_extent_uptodate(tree, eb->start, eb->start + eb->len - 1,
- NULL, GFP_NOFS);
- }
for (i = 0; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
- if ((i == 0 && (eb->start & (PAGE_CACHE_SIZE - 1))) ||
- ((i == num_pages - 1) &&
- ((eb->start + eb->len) & (PAGE_CACHE_SIZE - 1)))) {
- check_page_uptodate(tree, page);
- continue;
- }
SetPageUptodate(page);
}
return 0;
@@ -3917,7 +4382,7 @@ int extent_range_uptodate(struct extent_io_tree *tree,
int uptodate;
unsigned long index;
- if (__eb_straddles_pages(start, end - start + 1)) {
+ if (range_straddles_pages(start, end - start + 1)) {
ret = test_range_bit(tree, start, end,
EXTENT_UPTODATE, 1, NULL);
if (ret)
@@ -3939,35 +4404,9 @@ int extent_range_uptodate(struct extent_io_tree *tree,
return pg_uptodate;
}
-int extent_buffer_uptodate(struct extent_io_tree *tree,
- struct extent_buffer *eb,
- struct extent_state *cached_state)
+int extent_buffer_uptodate(struct extent_buffer *eb)
{
- int ret = 0;
- unsigned long num_pages;
- unsigned long i;
- struct page *page;
- int pg_uptodate = 1;
-
- if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
- return 1;
-
- if (eb_straddles_pages(eb)) {
- ret = test_range_bit(tree, eb->start, eb->start + eb->len - 1,
- EXTENT_UPTODATE, 1, cached_state);
- if (ret)
- return ret;
- }
-
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- if (!PageUptodate(page)) {
- pg_uptodate = 0;
- break;
- }
- }
- return pg_uptodate;
+ return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
}
int read_extent_buffer_pages(struct extent_io_tree *tree,
@@ -3981,21 +4420,14 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
int ret = 0;
int locked_pages = 0;
int all_uptodate = 1;
- int inc_all_pages = 0;
unsigned long num_pages;
+ unsigned long num_reads = 0;
struct bio *bio = NULL;
unsigned long bio_flags = 0;
if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
return 0;
- if (eb_straddles_pages(eb)) {
- if (test_range_bit(tree, eb->start, eb->start + eb->len - 1,
- EXTENT_UPTODATE, 1, NULL)) {
- return 0;
- }
- }
-
if (start) {
WARN_ON(start < eb->start);
start_i = (start >> PAGE_CACHE_SHIFT) -
@@ -4014,8 +4446,10 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
lock_page(page);
}
locked_pages++;
- if (!PageUptodate(page))
+ if (!PageUptodate(page)) {
+ num_reads++;
all_uptodate = 0;
+ }
}
if (all_uptodate) {
if (start_i == 0)
@@ -4023,20 +4457,12 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
goto unlock_exit;
}
+ clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
+ eb->failed_mirror = 0;
+ atomic_set(&eb->io_pages, num_reads);
for (i = start_i; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
-
- WARN_ON(!PagePrivate(page));
-
- set_page_extent_mapped(page);
- if (i == 0)
- set_page_extent_head(page, eb->len);
-
- if (inc_all_pages)
- page_cache_get(page);
if (!PageUptodate(page)) {
- if (start_i == 0)
- inc_all_pages = 1;
ClearPageError(page);
err = __extent_read_full_page(tree, page,
get_extent, &bio,
@@ -4048,8 +4474,11 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
}
}
- if (bio)
- submit_one_bio(READ, bio, mirror_num, bio_flags);
+ if (bio) {
+ err = submit_one_bio(READ, bio, mirror_num, bio_flags);
+ if (err)
+ return err;
+ }
if (ret || wait != WAIT_COMPLETE)
return ret;
@@ -4061,8 +4490,6 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
ret = -EIO;
}
- if (!ret)
- set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
return ret;
unlock_exit:
@@ -4304,15 +4731,20 @@ static void copy_pages(struct page *dst_page, struct page *src_page,
{
char *dst_kaddr = page_address(dst_page);
char *src_kaddr;
+ int must_memmove = 0;
if (dst_page != src_page) {
src_kaddr = page_address(src_page);
} else {
src_kaddr = dst_kaddr;
- BUG_ON(areas_overlap(src_off, dst_off, len));
+ if (areas_overlap(src_off, dst_off, len))
+ must_memmove = 1;
}
- memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
+ if (must_memmove)
+ memmove(dst_kaddr + dst_off, src_kaddr + src_off, len);
+ else
+ memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
}
void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
@@ -4382,7 +4814,7 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
"len %lu len %lu\n", dst_offset, len, dst->len);
BUG_ON(1);
}
- if (!areas_overlap(src_offset, dst_offset, len)) {
+ if (dst_offset < src_offset) {
memcpy_extent_buffer(dst, dst_offset, src_offset, len);
return;
}
@@ -4408,47 +4840,48 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
}
}
-static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
+int try_release_extent_buffer(struct page *page, gfp_t mask)
{
- struct extent_buffer *eb =
- container_of(head, struct extent_buffer, rcu_head);
-
- btrfs_release_extent_buffer(eb);
-}
-
-int try_release_extent_buffer(struct extent_io_tree *tree, struct page *page)
-{
- u64 start = page_offset(page);
struct extent_buffer *eb;
- int ret = 1;
- spin_lock(&tree->buffer_lock);
- eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
- if (!eb) {
- spin_unlock(&tree->buffer_lock);
- return ret;
+ /*
+ * We need to make sure noboody is attaching this page to an eb right
+ * now.
+ */
+ spin_lock(&page->mapping->private_lock);
+ if (!PagePrivate(page)) {
+ spin_unlock(&page->mapping->private_lock);
+ return 1;
}
- if (test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
- ret = 0;
- goto out;
- }
+ eb = (struct extent_buffer *)page->private;
+ BUG_ON(!eb);
/*
- * set @eb->refs to 0 if it is already 1, and then release the @eb.
- * Or go back.
+ * This is a little awful but should be ok, we need to make sure that
+ * the eb doesn't disappear out from under us while we're looking at
+ * this page.
*/
- if (atomic_cmpxchg(&eb->refs, 1, 0) != 1) {
- ret = 0;
- goto out;
+ spin_lock(&eb->refs_lock);
+ if (atomic_read(&eb->refs) != 1 || extent_buffer_under_io(eb)) {
+ spin_unlock(&eb->refs_lock);
+ spin_unlock(&page->mapping->private_lock);
+ return 0;
}
+ spin_unlock(&page->mapping->private_lock);
- radix_tree_delete(&tree->buffer, start >> PAGE_CACHE_SHIFT);
-out:
- spin_unlock(&tree->buffer_lock);
+ if ((mask & GFP_NOFS) == GFP_NOFS)
+ mask = GFP_NOFS;
- /* at this point we can safely release the extent buffer */
- if (atomic_read(&eb->refs) == 0)
- call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
- return ret;
+ /*
+ * If tree ref isn't set then we know the ref on this eb is a real ref,
+ * so just return, this page will likely be freed soon anyway.
+ */
+ if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) {
+ spin_unlock(&eb->refs_lock);
+ return 0;
+ }
+ release_extent_buffer(eb, mask);
+
+ return 1;
}