#define btrfs_debug_check_extent_io_range(c, s, e) do {} while (0)
#endif
-#define BUFFER_LRU_MAX 64
-
struct tree_entry {
u64 start;
u64 end;
return blk_status_to_errno(ret);
}
-static void flush_write_bio(struct extent_page_data *epd)
+/* Cleanup unsubmitted bios */
+static void end_write_bio(struct extent_page_data *epd, int ret)
{
if (epd->bio) {
- int ret;
+ epd->bio->bi_status = errno_to_blk_status(ret);
+ bio_endio(epd->bio);
+ epd->bio = NULL;
+ }
+}
+/*
+ * Submit bio from extent page data via submit_one_bio
+ *
+ * Return 0 if everything is OK.
+ * Return <0 for error.
+ */
+static int __must_check flush_write_bio(struct extent_page_data *epd)
+{
+ int ret = 0;
+
+ if (epd->bio) {
ret = submit_one_bio(epd->bio, 0, 0);
- BUG_ON(ret < 0); /* -ENOMEM */
+ /*
+ * Clean up of epd->bio is handled by its endio function.
+ * And endio is either triggered by successful bio execution
+ * or the error handler of submit bio hook.
+ * So at this point, no matter what happened, we don't need
+ * to clean up epd->bio.
+ */
epd->bio = NULL;
}
+ return ret;
}
int __init extent_io_init(void)
if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD,
&eb->bflags))
btree_readahead_hook(eb, -EIO);
-
- ret = -EIO;
}
readpage_ok:
if (likely(uptodate)) {
return ret;
}
-static inline void __do_contiguous_readpages(struct extent_io_tree *tree,
+static inline void contiguous_readpages(struct extent_io_tree *tree,
struct page *pages[], int nr_pages,
u64 start, u64 end,
struct extent_map **em_cached,
}
}
-static void __extent_readpages(struct extent_io_tree *tree,
- struct page *pages[],
- int nr_pages,
- struct extent_map **em_cached,
- struct bio **bio, unsigned long *bio_flags,
- u64 *prev_em_start)
-{
- u64 start = 0;
- u64 end = 0;
- u64 page_start;
- int index;
- int first_index = 0;
-
- for (index = 0; index < nr_pages; index++) {
- page_start = page_offset(pages[index]);
- if (!end) {
- start = page_start;
- end = start + PAGE_SIZE - 1;
- first_index = index;
- } else if (end + 1 == page_start) {
- end += PAGE_SIZE;
- } else {
- __do_contiguous_readpages(tree, &pages[first_index],
- index - first_index, start,
- end, em_cached,
- bio, bio_flags,
- prev_em_start);
- start = page_start;
- end = start + PAGE_SIZE - 1;
- first_index = index;
- }
- }
-
- if (end)
- __do_contiguous_readpages(tree, &pages[first_index],
- index - first_index, start,
- end, em_cached, bio,
- bio_flags, prev_em_start);
-}
-
static int __extent_read_full_page(struct extent_io_tree *tree,
struct page *page,
get_extent_t *get_extent,
* records are inserted to lock ranges in the tree, and as dirty areas
* are found, they are marked writeback. Then the lock bits are removed
* and the end_io handler clears the writeback ranges
+ *
+ * Return 0 if everything goes well.
+ * Return <0 for error.
*/
static int __extent_writepage(struct page *page, struct writeback_control *wbc,
struct extent_page_data *epd)
end_extent_writepage(page, ret, start, page_end);
}
unlock_page(page);
+ ASSERT(ret <= 0);
return ret;
done_unlocked:
TASK_UNINTERRUPTIBLE);
}
+/*
+ * Lock eb pages and flush the bio if we can't the locks
+ *
+ * Return 0 if nothing went wrong
+ * Return >0 is same as 0, except bio is not submitted
+ * Return <0 if something went wrong, no page is locked
+ */
static noinline_for_stack int
lock_extent_buffer_for_io(struct extent_buffer *eb,
struct btrfs_fs_info *fs_info,
struct extent_page_data *epd)
{
- int i, num_pages;
+ int i, num_pages, failed_page_nr;
int flush = 0;
int ret = 0;
if (!btrfs_try_tree_write_lock(eb)) {
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ return ret;
flush = 1;
- flush_write_bio(epd);
btrfs_tree_lock(eb);
}
if (!epd->sync_io)
return 0;
if (!flush) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ if (ret < 0)
+ return ret;
flush = 1;
}
while (1) {
if (!trylock_page(p)) {
if (!flush) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ if (ret < 0) {
+ failed_page_nr = i;
+ goto err_unlock;
+ }
flush = 1;
}
lock_page(p);
}
return ret;
+err_unlock:
+ /* Unlock already locked pages */
+ for (i = 0; i < failed_page_nr; i++)
+ unlock_page(eb->pages[i]);
+ return ret;
}
static void end_extent_buffer_writeback(struct extent_buffer *eb)
index = 0;
goto retry;
}
- flush_write_bio(&epd);
+ ASSERT(ret <= 0);
+ if (ret < 0) {
+ end_write_bio(&epd, ret);
+ return ret;
+ }
+ ret = flush_write_bio(&epd);
return ret;
}
* tmpfs file mapping
*/
if (!trylock_page(page)) {
- flush_write_bio(epd);
+ ret = flush_write_bio(epd);
+ BUG_ON(ret < 0);
lock_page(page);
}
}
if (wbc->sync_mode != WB_SYNC_NONE) {
- if (PageWriteback(page))
- flush_write_bio(epd);
+ if (PageWriteback(page)) {
+ ret = flush_write_bio(epd);
+ BUG_ON(ret < 0);
+ }
wait_on_page_writeback(page);
}
}
ret = __extent_writepage(page, wbc, epd);
-
- if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
- unlock_page(page);
- ret = 0;
- }
if (ret < 0) {
/*
* done_index is set past this page,
};
ret = __extent_writepage(page, wbc, &epd);
+ ASSERT(ret <= 0);
+ if (ret < 0) {
+ end_write_bio(&epd, ret);
+ return ret;
+ }
- flush_write_bio(&epd);
+ ret = flush_write_bio(&epd);
+ ASSERT(ret <= 0);
return ret;
}
start += PAGE_SIZE;
}
- flush_write_bio(&epd);
+ ASSERT(ret <= 0);
+ if (ret < 0) {
+ end_write_bio(&epd, ret);
+ return ret;
+ }
+ ret = flush_write_bio(&epd);
return ret;
}
};
ret = extent_write_cache_pages(mapping, wbc, &epd);
- flush_write_bio(&epd);
+ ASSERT(ret <= 0);
+ if (ret < 0) {
+ end_write_bio(&epd, ret);
+ return ret;
+ }
+ ret = flush_write_bio(&epd);
return ret;
}
u64 prev_em_start = (u64)-1;
while (!list_empty(pages)) {
+ u64 contig_end = 0;
+
for (nr = 0; nr < ARRAY_SIZE(pagepool) && !list_empty(pages);) {
struct page *page = lru_to_page(pages);
if (add_to_page_cache_lru(page, mapping, page->index,
readahead_gfp_mask(mapping))) {
put_page(page);
- continue;
+ break;
}
pagepool[nr++] = page;
+ contig_end = page_offset(page) + PAGE_SIZE - 1;
}
- __extent_readpages(tree, pagepool, nr, &em_cached, &bio,
- &bio_flags, &prev_em_start);
+ if (nr) {
+ u64 contig_start = page_offset(pagepool[0]);
+
+ ASSERT(contig_start + nr * PAGE_SIZE - 1 == contig_end);
+
+ contiguous_readpages(tree, pagepool, nr, contig_start,
+ contig_end, &em_cached, &bio, &bio_flags,
+ &prev_em_start);
+ }
}
if (em_cached)
eb->fs_info = fs_info;
eb->bflags = 0;
rwlock_init(&eb->lock);
- atomic_set(&eb->write_locks, 0);
- atomic_set(&eb->read_locks, 0);
atomic_set(&eb->blocking_readers, 0);
atomic_set(&eb->blocking_writers, 0);
- atomic_set(&eb->spinning_readers, 0);
- eb->lock_nested = 0;
+ eb->lock_nested = false;
init_waitqueue_head(&eb->write_lock_wq);
init_waitqueue_head(&eb->read_lock_wq);
#ifdef CONFIG_BTRFS_DEBUG
atomic_set(&eb->spinning_writers, 0);
+ atomic_set(&eb->spinning_readers, 0);
+ atomic_set(&eb->read_locks, 0);
+ atomic_set(&eb->write_locks, 0);
#endif
return eb;
git.samba.org / sfrench / cifs-2.6.git / blobdiff