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Diffstat (limited to 'kernel/fs/direct-io.c')
-rw-r--r--kernel/fs/direct-io.c54
1 files changed, 37 insertions, 17 deletions
diff --git a/kernel/fs/direct-io.c b/kernel/fs/direct-io.c
index 745d23426..01171d8a6 100644
--- a/kernel/fs/direct-io.c
+++ b/kernel/fs/direct-io.c
@@ -109,6 +109,8 @@ struct dio_submit {
struct dio {
int flags; /* doesn't change */
int rw;
+ blk_qc_t bio_cookie;
+ struct block_device *bio_bdev;
struct inode *inode;
loff_t i_size; /* i_size when submitted */
dio_iodone_t *end_io; /* IO completion function */
@@ -120,6 +122,7 @@ struct dio {
int page_errors; /* errno from get_user_pages() */
int is_async; /* is IO async ? */
bool defer_completion; /* defer AIO completion to workqueue? */
+ bool should_dirty; /* if pages should be dirtied */
int io_error; /* IO error in completion path */
unsigned long refcount; /* direct_io_worker() and bios */
struct bio *bio_list; /* singly linked via bi_private */
@@ -285,7 +288,7 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio);
/*
* Asynchronous IO callback.
*/
-static void dio_bio_end_aio(struct bio *bio, int error)
+static void dio_bio_end_aio(struct bio *bio)
{
struct dio *dio = bio->bi_private;
unsigned long remaining;
@@ -318,7 +321,7 @@ static void dio_bio_end_aio(struct bio *bio, int error)
* During I/O bi_private points at the dio. After I/O, bi_private is used to
* implement a singly-linked list of completed BIOs, at dio->bio_list.
*/
-static void dio_bio_end_io(struct bio *bio, int error)
+static void dio_bio_end_io(struct bio *bio)
{
struct dio *dio = bio->bi_private;
unsigned long flags;
@@ -345,9 +348,9 @@ void dio_end_io(struct bio *bio, int error)
struct dio *dio = bio->bi_private;
if (dio->is_async)
- dio_bio_end_aio(bio, error);
+ dio_bio_end_aio(bio);
else
- dio_bio_end_io(bio, error);
+ dio_bio_end_io(bio);
}
EXPORT_SYMBOL_GPL(dio_end_io);
@@ -360,7 +363,7 @@ dio_bio_alloc(struct dio *dio, struct dio_submit *sdio,
/*
* bio_alloc() is guaranteed to return a bio when called with
- * __GFP_WAIT and we request a valid number of vectors.
+ * __GFP_RECLAIM and we request a valid number of vectors.
*/
bio = bio_alloc(GFP_KERNEL, nr_vecs);
@@ -393,14 +396,17 @@ static inline void dio_bio_submit(struct dio *dio, struct dio_submit *sdio)
dio->refcount++;
spin_unlock_irqrestore(&dio->bio_lock, flags);
- if (dio->is_async && dio->rw == READ)
+ if (dio->is_async && dio->rw == READ && dio->should_dirty)
bio_set_pages_dirty(bio);
- if (sdio->submit_io)
+ dio->bio_bdev = bio->bi_bdev;
+
+ if (sdio->submit_io) {
sdio->submit_io(dio->rw, bio, dio->inode,
sdio->logical_offset_in_bio);
- else
- submit_bio(dio->rw, bio);
+ dio->bio_cookie = BLK_QC_T_NONE;
+ } else
+ dio->bio_cookie = submit_bio(dio->rw, bio);
sdio->bio = NULL;
sdio->boundary = 0;
@@ -439,7 +445,8 @@ static struct bio *dio_await_one(struct dio *dio)
__set_current_state(TASK_UNINTERRUPTIBLE);
dio->waiter = current;
spin_unlock_irqrestore(&dio->bio_lock, flags);
- io_schedule();
+ if (!blk_poll(bdev_get_queue(dio->bio_bdev), dio->bio_cookie))
+ io_schedule();
/* wake up sets us TASK_RUNNING */
spin_lock_irqsave(&dio->bio_lock, flags);
dio->waiter = NULL;
@@ -457,26 +464,29 @@ static struct bio *dio_await_one(struct dio *dio)
*/
static int dio_bio_complete(struct dio *dio, struct bio *bio)
{
- const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
struct bio_vec *bvec;
unsigned i;
+ int err;
- if (!uptodate)
+ if (bio->bi_error)
dio->io_error = -EIO;
- if (dio->is_async && dio->rw == READ) {
+ if (dio->is_async && dio->rw == READ && dio->should_dirty) {
+ err = bio->bi_error;
bio_check_pages_dirty(bio); /* transfers ownership */
} else {
bio_for_each_segment_all(bvec, bio, i) {
struct page *page = bvec->bv_page;
- if (dio->rw == READ && !PageCompound(page))
+ if (dio->rw == READ && !PageCompound(page) &&
+ dio->should_dirty)
set_page_dirty_lock(page);
page_cache_release(page);
}
+ err = bio->bi_error;
bio_put(bio);
}
- return uptodate ? 0 : -EIO;
+ return err;
}
/*
@@ -653,7 +663,7 @@ static inline int dio_new_bio(struct dio *dio, struct dio_submit *sdio,
if (ret)
goto out;
sector = start_sector << (sdio->blkbits - 9);
- nr_pages = min(sdio->pages_in_io, bio_get_nr_vecs(map_bh->b_bdev));
+ nr_pages = min(sdio->pages_in_io, BIO_MAX_PAGES);
BUG_ON(nr_pages <= 0);
dio_bio_alloc(dio, sdio, map_bh->b_bdev, sector, nr_pages);
sdio->boundary = 0;
@@ -1159,6 +1169,16 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
}
}
+ /* Once we sampled i_size check for reads beyond EOF */
+ dio->i_size = i_size_read(inode);
+ if (iov_iter_rw(iter) == READ && offset >= dio->i_size) {
+ if (dio->flags & DIO_LOCKING)
+ mutex_unlock(&inode->i_mutex);
+ kmem_cache_free(dio_cache, dio);
+ retval = 0;
+ goto out;
+ }
+
/*
* For file extending writes updating i_size before data writeouts
* complete can expose uninitialized blocks in dumb filesystems.
@@ -1212,11 +1232,11 @@ do_blockdev_direct_IO(struct kiocb *iocb, struct inode *inode,
sdio.next_block_for_io = -1;
dio->iocb = iocb;
- dio->i_size = i_size_read(inode);
spin_lock_init(&dio->bio_lock);
dio->refcount = 1;
+ dio->should_dirty = (iter->type == ITER_IOVEC);
sdio.iter = iter;
sdio.final_block_in_request =
(offset + iov_iter_count(iter)) >> blkbits;