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Diffstat (limited to 'fs/ext4/page-io.c')
-rw-r--r--fs/ext4/page-io.c99
1 files changed, 50 insertions, 49 deletions
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 46a7d6a9d976..beacce11ac50 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -32,8 +32,14 @@
static struct kmem_cache *io_page_cachep, *io_end_cachep;
+#define WQ_HASH_SZ 37
+#define to_ioend_wq(v) (&ioend_wq[((unsigned long)v) % WQ_HASH_SZ])
+static wait_queue_head_t ioend_wq[WQ_HASH_SZ];
+
int __init ext4_init_pageio(void)
{
+ int i;
+
io_page_cachep = KMEM_CACHE(ext4_io_page, SLAB_RECLAIM_ACCOUNT);
if (io_page_cachep == NULL)
return -ENOMEM;
@@ -42,6 +48,8 @@ int __init ext4_init_pageio(void)
kmem_cache_destroy(io_page_cachep);
return -ENOMEM;
}
+ for (i = 0; i < WQ_HASH_SZ; i++)
+ init_waitqueue_head(&ioend_wq[i]);
return 0;
}
@@ -52,24 +60,37 @@ void ext4_exit_pageio(void)
kmem_cache_destroy(io_page_cachep);
}
+void ext4_ioend_wait(struct inode *inode)
+{
+ wait_queue_head_t *wq = to_ioend_wq(inode);
+
+ wait_event(*wq, (atomic_read(&EXT4_I(inode)->i_ioend_count) == 0));
+}
+
+static void put_io_page(struct ext4_io_page *io_page)
+{
+ if (atomic_dec_and_test(&io_page->p_count)) {
+ end_page_writeback(io_page->p_page);
+ put_page(io_page->p_page);
+ kmem_cache_free(io_page_cachep, io_page);
+ }
+}
+
void ext4_free_io_end(ext4_io_end_t *io)
{
int i;
+ wait_queue_head_t *wq;
BUG_ON(!io);
if (io->page)
put_page(io->page);
- for (i = 0; i < io->num_io_pages; i++) {
- if (--io->pages[i]->p_count == 0) {
- struct page *page = io->pages[i]->p_page;
-
- end_page_writeback(page);
- put_page(page);
- kmem_cache_free(io_page_cachep, io->pages[i]);
- }
- }
+ for (i = 0; i < io->num_io_pages; i++)
+ put_io_page(io->pages[i]);
io->num_io_pages = 0;
- iput(io->inode);
+ wq = to_ioend_wq(io->inode);
+ if (atomic_dec_and_test(&EXT4_I(io->inode)->i_ioend_count) &&
+ waitqueue_active(wq))
+ wake_up_all(wq);
kmem_cache_free(io_end_cachep, io);
}
@@ -142,8 +163,8 @@ ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags)
io = kmem_cache_alloc(io_end_cachep, flags);
if (io) {
memset(io, 0, sizeof(*io));
- io->inode = igrab(inode);
- BUG_ON(!io->inode);
+ atomic_inc(&EXT4_I(inode)->i_ioend_count);
+ io->inode = inode;
INIT_WORK(&io->work, ext4_end_io_work);
INIT_LIST_HEAD(&io->list);
}
@@ -171,35 +192,15 @@ static void ext4_end_bio(struct bio *bio, int error)
struct workqueue_struct *wq;
struct inode *inode;
unsigned long flags;
- ext4_fsblk_t err_block;
int i;
BUG_ON(!io_end);
- inode = io_end->inode;
bio->bi_private = NULL;
bio->bi_end_io = NULL;
if (test_bit(BIO_UPTODATE, &bio->bi_flags))
error = 0;
- err_block = bio->bi_sector >> (inode->i_blkbits - 9);
bio_put(bio);
- if (!(inode->i_sb->s_flags & MS_ACTIVE)) {
- pr_err("sb umounted, discard end_io request for inode %lu\n",
- io_end->inode->i_ino);
- ext4_free_io_end(io_end);
- return;
- }
-
- if (error) {
- io_end->flag |= EXT4_IO_END_ERROR;
- ext4_warning(inode->i_sb, "I/O error writing to inode %lu "
- "(offset %llu size %ld starting block %llu)",
- inode->i_ino,
- (unsigned long long) io_end->offset,
- (long) io_end->size,
- (unsigned long long) err_block);
- }
-
for (i = 0; i < io_end->num_io_pages; i++) {
struct page *page = io_end->pages[i]->p_page;
struct buffer_head *bh, *head;
@@ -236,14 +237,6 @@ static void ext4_end_bio(struct bio *bio, int error)
} while (bh != head);
}
- if (--io_end->pages[i]->p_count == 0) {
- struct page *page = io_end->pages[i]->p_page;
-
- end_page_writeback(page);
- put_page(page);
- kmem_cache_free(io_page_cachep, io_end->pages[i]);
- }
-
/*
* If this is a partial write which happened to make
* all buffers uptodate then we can optimize away a
@@ -253,9 +246,22 @@ static void ext4_end_bio(struct bio *bio, int error)
*/
if (!partial_write)
SetPageUptodate(page);
- }
+ put_io_page(io_end->pages[i]);
+ }
io_end->num_io_pages = 0;
+ inode = io_end->inode;
+
+ if (error) {
+ io_end->flag |= EXT4_IO_END_ERROR;
+ ext4_warning(inode->i_sb, "I/O error writing to inode %lu "
+ "(offset %llu size %ld starting block %llu)",
+ inode->i_ino,
+ (unsigned long long) io_end->offset,
+ (long) io_end->size,
+ (unsigned long long)
+ bio->bi_sector >> (inode->i_blkbits - 9));
+ }
/* Add the io_end to per-inode completed io list*/
spin_lock_irqsave(&EXT4_I(inode)->i_completed_io_lock, flags);
@@ -305,7 +311,6 @@ static int io_submit_init(struct ext4_io_submit *io,
bio->bi_private = io->io_end = io_end;
bio->bi_end_io = ext4_end_bio;
- io_end->inode = inode;
io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh);
io->io_bio = bio;
@@ -360,7 +365,7 @@ submit_and_retry:
if ((io_end->num_io_pages == 0) ||
(io_end->pages[io_end->num_io_pages-1] != io_page)) {
io_end->pages[io_end->num_io_pages++] = io_page;
- io_page->p_count++;
+ atomic_inc(&io_page->p_count);
}
return 0;
}
@@ -389,7 +394,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
return -ENOMEM;
}
io_page->p_page = page;
- io_page->p_count = 0;
+ atomic_set(&io_page->p_count, 1);
get_page(page);
for (bh = head = page_buffers(page), block_start = 0;
@@ -421,10 +426,6 @@ int ext4_bio_write_page(struct ext4_io_submit *io,
* PageWriteback bit from the page to prevent the system from
* wedging later on.
*/
- if (io_page->p_count == 0) {
- put_page(page);
- end_page_writeback(page);
- kmem_cache_free(io_page_cachep, io_page);
- }
+ put_io_page(io_page);
return ret;
}