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Diffstat (limited to 'fs/btrfs/extent_io.c')
-rw-r--r--fs/btrfs/extent_io.c156
1 files changed, 67 insertions, 89 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index b3e45714d28f..628f1aef34b0 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -140,14 +140,6 @@ static int add_extent_changeset(struct extent_state *state, unsigned bits,
static void flush_write_bio(struct extent_page_data *epd);
-static inline struct btrfs_fs_info *
-tree_fs_info(struct extent_io_tree *tree)
-{
- if (tree->ops)
- return tree->ops->tree_fs_info(tree->private_data);
- return NULL;
-}
-
int __init extent_io_init(void)
{
extent_state_cache = kmem_cache_create("btrfs_extent_state",
@@ -564,8 +556,10 @@ alloc_extent_state_atomic(struct extent_state *prealloc)
static 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.");
+ struct inode *inode = tree->private_data;
+
+ btrfs_panic(btrfs_sb(inode->i_sb), err,
+ "locking error: extent tree was modified by another thread while locked");
}
/*
@@ -1386,14 +1380,6 @@ void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end)
}
}
-/*
- * helper function to set both pages and extents in the tree writeback
- */
-static void set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
-{
- tree->ops->set_range_writeback(tree->private_data, start, end);
-}
-
/* find the first state struct with 'bits' set after 'start', and
* return it. tree->lock must be held. NULL will returned if
* nothing was found after 'start'
@@ -2059,7 +2045,7 @@ int repair_eb_io_failure(struct btrfs_fs_info *fs_info,
struct extent_buffer *eb, int mirror_num)
{
u64 start = eb->start;
- unsigned long i, num_pages = num_extent_pages(eb->start, eb->len);
+ int i, num_pages = num_extent_pages(eb);
int ret = 0;
if (sb_rdonly(fs_info->sb))
@@ -2398,7 +2384,7 @@ static int bio_readpage_error(struct bio *failed_bio, u64 phy_offset,
start - page_offset(page),
(int)phy_offset, failed_bio->bi_end_io,
NULL);
- bio_set_op_attrs(bio, REQ_OP_READ, read_mode);
+ bio->bi_opf = REQ_OP_READ | read_mode;
btrfs_debug(btrfs_sb(inode->i_sb),
"Repair Read Error: submitting new read[%#x] to this_mirror=%d, in_validation=%d",
@@ -2790,8 +2776,8 @@ static int submit_extent_page(unsigned int opf, struct extent_io_tree *tree,
else
contig = bio_end_sector(bio) == sector;
- if (tree->ops && tree->ops->merge_bio_hook(page, offset,
- page_size, bio, bio_flags))
+ if (tree->ops && btrfs_merge_bio_hook(page, offset, page_size,
+ bio, bio_flags))
can_merge = false;
if (prev_bio_flags != bio_flags || !contig || !can_merge ||
@@ -3422,7 +3408,7 @@ static noinline_for_stack int __extent_writepage_io(struct inode *inode,
continue;
}
- set_range_writeback(tree, cur, cur + iosize - 1);
+ btrfs_set_range_writeback(tree, cur, cur + iosize - 1);
if (!PageWriteback(page)) {
btrfs_err(BTRFS_I(inode)->root->fs_info,
"page %lu not writeback, cur %llu end %llu",
@@ -3538,7 +3524,7 @@ 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 i, num_pages;
int flush = 0;
int ret = 0;
@@ -3588,7 +3574,7 @@ lock_extent_buffer_for_io(struct extent_buffer *eb,
if (!ret)
return ret;
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
struct page *p = eb->pages[i];
@@ -3712,13 +3698,13 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb,
struct extent_io_tree *tree = &BTRFS_I(fs_info->btree_inode)->io_tree;
u64 offset = eb->start;
u32 nritems;
- unsigned long i, num_pages;
+ int i, num_pages;
unsigned long start, end;
unsigned int write_flags = wbc_to_write_flags(wbc) | REQ_META;
int ret = 0;
clear_bit(EXTENT_BUFFER_WRITE_ERR, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
atomic_set(&eb->io_pages, num_pages);
/* set btree blocks beyond nritems with 0 to avoid stale content. */
@@ -4643,23 +4629,20 @@ int extent_buffer_under_io(struct extent_buffer *eb)
}
/*
- * Helper for releasing extent buffer page.
+ * Release all pages attached to the extent buffer.
*/
-static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
+static void btrfs_release_extent_buffer_pages(struct extent_buffer *eb)
{
- unsigned long index;
- struct page *page;
- int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
+ int i;
+ int num_pages;
+ int mapped = !test_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags);
BUG_ON(extent_buffer_under_io(eb));
- index = num_extent_pages(eb->start, eb->len);
- if (index == 0)
- return;
+ num_pages = num_extent_pages(eb);
+ for (i = 0; i < num_pages; i++) {
+ struct page *page = eb->pages[i];
- do {
- index--;
- page = eb->pages[index];
if (!page)
continue;
if (mapped)
@@ -4691,7 +4674,7 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
/* One for when we allocated the page */
put_page(page);
- } while (index != 0);
+ }
}
/*
@@ -4699,7 +4682,7 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
*/
static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
{
- btrfs_release_extent_buffer_page(eb);
+ btrfs_release_extent_buffer_pages(eb);
__free_extent_buffer(eb);
}
@@ -4743,10 +4726,10 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src)
{
- unsigned long i;
+ int i;
struct page *p;
struct extent_buffer *new;
- unsigned long num_pages = num_extent_pages(src->start, src->len);
+ int num_pages = num_extent_pages(src);
new = __alloc_extent_buffer(src->fs_info, src->start, src->len);
if (new == NULL)
@@ -4766,7 +4749,7 @@ struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src)
}
set_bit(EXTENT_BUFFER_UPTODATE, &new->bflags);
- set_bit(EXTENT_BUFFER_DUMMY, &new->bflags);
+ set_bit(EXTENT_BUFFER_UNMAPPED, &new->bflags);
return new;
}
@@ -4775,15 +4758,14 @@ struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
u64 start, unsigned long len)
{
struct extent_buffer *eb;
- unsigned long num_pages;
- unsigned long i;
-
- num_pages = num_extent_pages(start, len);
+ int num_pages;
+ int i;
eb = __alloc_extent_buffer(fs_info, start, len);
if (!eb)
return NULL;
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
eb->pages[i] = alloc_page(GFP_NOFS);
if (!eb->pages[i])
@@ -4791,7 +4773,7 @@ struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info,
}
set_extent_buffer_uptodate(eb);
btrfs_set_header_nritems(eb, 0);
- set_bit(EXTENT_BUFFER_DUMMY, &eb->bflags);
+ set_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags);
return eb;
err:
@@ -4843,11 +4825,11 @@ static void check_buffer_tree_ref(struct extent_buffer *eb)
static void mark_extent_buffer_accessed(struct extent_buffer *eb,
struct page *accessed)
{
- unsigned long num_pages, i;
+ int num_pages, i;
check_buffer_tree_ref(eb);
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
struct page *p = eb->pages[i];
@@ -4944,8 +4926,8 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
u64 start)
{
unsigned long len = fs_info->nodesize;
- unsigned long num_pages = num_extent_pages(start, len);
- unsigned long i;
+ int num_pages;
+ int i;
unsigned long index = start >> PAGE_SHIFT;
struct extent_buffer *eb;
struct extent_buffer *exists = NULL;
@@ -4967,6 +4949,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
if (!eb)
return ERR_PTR(-ENOMEM);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++, index++) {
p = find_or_create_page(mapping, index, GFP_NOFS|__GFP_NOFAIL);
if (!p) {
@@ -5009,8 +4992,11 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
uptodate = 0;
/*
- * see below about how we avoid a nasty race with release page
- * and why we unlock later
+ * We can't unlock the pages just yet since the extent buffer
+ * hasn't been properly inserted in the radix tree, this
+ * opens a race with btree_releasepage which can free a page
+ * while we are still filling in all pages for the buffer and
+ * we could crash.
*/
}
if (uptodate)
@@ -5039,21 +5025,12 @@ again:
set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags);
/*
- * there is a race where release page may have
- * tried to find this extent buffer in the radix
- * but failed. It will tell the VM it is safe to
- * reclaim the, and it will clear the page private bit.
- * We must make sure to set the page private bit properly
- * after the extent buffer is in the radix tree so
- * it doesn't get lost
+ * Now it's safe to unlock the pages because any calls to
+ * btree_releasepage will correctly detect that a page belongs to a
+ * live buffer and won't free them prematurely.
*/
- SetPageChecked(eb->pages[0]);
- for (i = 1; i < num_pages; i++) {
- p = eb->pages[i];
- ClearPageChecked(p);
- unlock_page(p);
- }
- unlock_page(eb->pages[0]);
+ for (i = 0; i < num_pages; i++)
+ unlock_page(eb->pages[i]);
return eb;
free_eb:
@@ -5075,9 +5052,10 @@ static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
__free_extent_buffer(eb);
}
-/* Expects to have eb->eb_lock already held */
static int release_extent_buffer(struct extent_buffer *eb)
{
+ lockdep_assert_held(&eb->refs_lock);
+
WARN_ON(atomic_read(&eb->refs) == 0);
if (atomic_dec_and_test(&eb->refs)) {
if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags)) {
@@ -5094,9 +5072,9 @@ static int release_extent_buffer(struct extent_buffer *eb)
}
/* Should be safe to release our pages at this point */
- btrfs_release_extent_buffer_page(eb);
+ btrfs_release_extent_buffer_pages(eb);
#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
- if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))) {
+ if (unlikely(test_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags))) {
__free_extent_buffer(eb);
return 1;
}
@@ -5127,7 +5105,7 @@ void free_extent_buffer(struct extent_buffer *eb)
spin_lock(&eb->refs_lock);
if (atomic_read(&eb->refs) == 2 &&
- test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))
+ test_bit(EXTENT_BUFFER_UNMAPPED, &eb->bflags))
atomic_dec(&eb->refs);
if (atomic_read(&eb->refs) == 2 &&
@@ -5159,11 +5137,11 @@ void free_extent_buffer_stale(struct extent_buffer *eb)
void clear_extent_buffer_dirty(struct extent_buffer *eb)
{
- unsigned long i;
- unsigned long num_pages;
+ int i;
+ int num_pages;
struct page *page;
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
page = eb->pages[i];
@@ -5189,15 +5167,15 @@ void clear_extent_buffer_dirty(struct extent_buffer *eb)
int set_extent_buffer_dirty(struct extent_buffer *eb)
{
- unsigned long i;
- unsigned long num_pages;
+ int i;
+ int 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);
+ num_pages = num_extent_pages(eb);
WARN_ON(atomic_read(&eb->refs) == 0);
WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags));
@@ -5208,12 +5186,12 @@ int set_extent_buffer_dirty(struct extent_buffer *eb)
void clear_extent_buffer_uptodate(struct extent_buffer *eb)
{
- unsigned long i;
+ int i;
struct page *page;
- unsigned long num_pages;
+ int num_pages;
clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
page = eb->pages[i];
if (page)
@@ -5223,12 +5201,12 @@ void clear_extent_buffer_uptodate(struct extent_buffer *eb)
void set_extent_buffer_uptodate(struct extent_buffer *eb)
{
- unsigned long i;
+ int i;
struct page *page;
- unsigned long num_pages;
+ int num_pages;
set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
page = eb->pages[i];
SetPageUptodate(page);
@@ -5238,13 +5216,13 @@ void set_extent_buffer_uptodate(struct extent_buffer *eb)
int read_extent_buffer_pages(struct extent_io_tree *tree,
struct extent_buffer *eb, int wait, int mirror_num)
{
- unsigned long i;
+ int i;
struct page *page;
int err;
int ret = 0;
int locked_pages = 0;
int all_uptodate = 1;
- unsigned long num_pages;
+ int num_pages;
unsigned long num_reads = 0;
struct bio *bio = NULL;
unsigned long bio_flags = 0;
@@ -5252,7 +5230,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
return 0;
- num_pages = num_extent_pages(eb->start, eb->len);
+ num_pages = num_extent_pages(eb);
for (i = 0; i < num_pages; i++) {
page = eb->pages[i];
if (wait == WAIT_NONE) {
@@ -5576,11 +5554,11 @@ void copy_extent_buffer_full(struct extent_buffer *dst,
struct extent_buffer *src)
{
int i;
- unsigned num_pages;
+ int num_pages;
ASSERT(dst->len == src->len);
- num_pages = num_extent_pages(dst->start, dst->len);
+ num_pages = num_extent_pages(dst);
for (i = 0; i < num_pages; i++)
copy_page(page_address(dst->pages[i]),
page_address(src->pages[i]));