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-rw-r--r--fs/direct-io.c104
1 files changed, 36 insertions, 68 deletions
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 7600aacf531d..85882f6ba5f7 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -218,7 +218,7 @@ static struct page *dio_get_page(struct dio *dio)
218 * filesystems can use it to hold additional state between get_block calls and 218 * filesystems can use it to hold additional state between get_block calls and
219 * dio_complete. 219 * dio_complete.
220 */ 220 */
221static int dio_complete(struct dio *dio, loff_t offset, int ret) 221static ssize_t dio_complete(struct dio *dio, loff_t offset, ssize_t ret, bool is_async)
222{ 222{
223 ssize_t transferred = 0; 223 ssize_t transferred = 0;
224 224
@@ -239,14 +239,6 @@ static int dio_complete(struct dio *dio, loff_t offset, int ret)
239 transferred = dio->i_size - offset; 239 transferred = dio->i_size - offset;
240 } 240 }
241 241
242 if (dio->end_io && dio->result)
243 dio->end_io(dio->iocb, offset, transferred,
244 dio->map_bh.b_private);
245
246 if (dio->flags & DIO_LOCKING)
247 /* lockdep: non-owner release */
248 up_read_non_owner(&dio->inode->i_alloc_sem);
249
250 if (ret == 0) 242 if (ret == 0)
251 ret = dio->page_errors; 243 ret = dio->page_errors;
252 if (ret == 0) 244 if (ret == 0)
@@ -254,6 +246,17 @@ static int dio_complete(struct dio *dio, loff_t offset, int ret)
254 if (ret == 0) 246 if (ret == 0)
255 ret = transferred; 247 ret = transferred;
256 248
249 if (dio->end_io && dio->result) {
250 dio->end_io(dio->iocb, offset, transferred,
251 dio->map_bh.b_private, ret, is_async);
252 } else if (is_async) {
253 aio_complete(dio->iocb, ret, 0);
254 }
255
256 if (dio->flags & DIO_LOCKING)
257 /* lockdep: non-owner release */
258 up_read_non_owner(&dio->inode->i_alloc_sem);
259
257 return ret; 260 return ret;
258} 261}
259 262
@@ -277,8 +280,7 @@ static void dio_bio_end_aio(struct bio *bio, int error)
277 spin_unlock_irqrestore(&dio->bio_lock, flags); 280 spin_unlock_irqrestore(&dio->bio_lock, flags);
278 281
279 if (remaining == 0) { 282 if (remaining == 0) {
280 int ret = dio_complete(dio, dio->iocb->ki_pos, 0); 283 dio_complete(dio, dio->iocb->ki_pos, 0, true);
281 aio_complete(dio->iocb, ret, 0);
282 kfree(dio); 284 kfree(dio);
283 } 285 }
284} 286}
@@ -632,7 +634,7 @@ static int dio_send_cur_page(struct dio *dio)
632 int ret = 0; 634 int ret = 0;
633 635
634 if (dio->bio) { 636 if (dio->bio) {
635 loff_t cur_offset = dio->block_in_file << dio->blkbits; 637 loff_t cur_offset = dio->cur_page_fs_offset;
636 loff_t bio_next_offset = dio->logical_offset_in_bio + 638 loff_t bio_next_offset = dio->logical_offset_in_bio +
637 dio->bio->bi_size; 639 dio->bio->bi_size;
638 640
@@ -657,7 +659,7 @@ static int dio_send_cur_page(struct dio *dio)
657 * Submit now if the underlying fs is about to perform a 659 * Submit now if the underlying fs is about to perform a
658 * metadata read 660 * metadata read
659 */ 661 */
660 if (dio->boundary) 662 else if (dio->boundary)
661 dio_bio_submit(dio); 663 dio_bio_submit(dio);
662 } 664 }
663 665
@@ -1126,7 +1128,7 @@ direct_io_worker(int rw, struct kiocb *iocb, struct inode *inode,
1126 spin_unlock_irqrestore(&dio->bio_lock, flags); 1128 spin_unlock_irqrestore(&dio->bio_lock, flags);
1127 1129
1128 if (ret2 == 0) { 1130 if (ret2 == 0) {
1129 ret = dio_complete(dio, offset, ret); 1131 ret = dio_complete(dio, offset, ret, false);
1130 kfree(dio); 1132 kfree(dio);
1131 } else 1133 } else
1132 BUG_ON(ret != -EIOCBQUEUED); 1134 BUG_ON(ret != -EIOCBQUEUED);
@@ -1134,8 +1136,27 @@ direct_io_worker(int rw, struct kiocb *iocb, struct inode *inode,
1134 return ret; 1136 return ret;
1135} 1137}
1136 1138
1139/*
1140 * This is a library function for use by filesystem drivers.
1141 *
1142 * The locking rules are governed by the flags parameter:
1143 * - if the flags value contains DIO_LOCKING we use a fancy locking
1144 * scheme for dumb filesystems.
1145 * For writes this function is called under i_mutex and returns with
1146 * i_mutex held, for reads, i_mutex is not held on entry, but it is
1147 * taken and dropped again before returning.
1148 * For reads and writes i_alloc_sem is taken in shared mode and released
1149 * on I/O completion (which may happen asynchronously after returning to
1150 * the caller).
1151 *
1152 * - if the flags value does NOT contain DIO_LOCKING we don't use any
1153 * internal locking but rather rely on the filesystem to synchronize
1154 * direct I/O reads/writes versus each other and truncate.
1155 * For reads and writes both i_mutex and i_alloc_sem are not held on
1156 * entry and are never taken.
1157 */
1137ssize_t 1158ssize_t
1138__blockdev_direct_IO_newtrunc(int rw, struct kiocb *iocb, struct inode *inode, 1159__blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1139 struct block_device *bdev, const struct iovec *iov, loff_t offset, 1160 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1140 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io, 1161 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
1141 dio_submit_t submit_io, int flags) 1162 dio_submit_t submit_io, int flags)
@@ -1231,57 +1252,4 @@ __blockdev_direct_IO_newtrunc(int rw, struct kiocb *iocb, struct inode *inode,
1231out: 1252out:
1232 return retval; 1253 return retval;
1233} 1254}
1234EXPORT_SYMBOL(__blockdev_direct_IO_newtrunc);
1235
1236/*
1237 * This is a library function for use by filesystem drivers.
1238 *
1239 * The locking rules are governed by the flags parameter:
1240 * - if the flags value contains DIO_LOCKING we use a fancy locking
1241 * scheme for dumb filesystems.
1242 * For writes this function is called under i_mutex and returns with
1243 * i_mutex held, for reads, i_mutex is not held on entry, but it is
1244 * taken and dropped again before returning.
1245 * For reads and writes i_alloc_sem is taken in shared mode and released
1246 * on I/O completion (which may happen asynchronously after returning to
1247 * the caller).
1248 *
1249 * - if the flags value does NOT contain DIO_LOCKING we don't use any
1250 * internal locking but rather rely on the filesystem to synchronize
1251 * direct I/O reads/writes versus each other and truncate.
1252 * For reads and writes both i_mutex and i_alloc_sem are not held on
1253 * entry and are never taken.
1254 */
1255ssize_t
1256__blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode,
1257 struct block_device *bdev, const struct iovec *iov, loff_t offset,
1258 unsigned long nr_segs, get_block_t get_block, dio_iodone_t end_io,
1259 dio_submit_t submit_io, int flags)
1260{
1261 ssize_t retval;
1262
1263 retval = __blockdev_direct_IO_newtrunc(rw, iocb, inode, bdev, iov,
1264 offset, nr_segs, get_block, end_io, submit_io, flags);
1265 /*
1266 * In case of error extending write may have instantiated a few
1267 * blocks outside i_size. Trim these off again for DIO_LOCKING.
1268 * NOTE: DIO_NO_LOCK/DIO_OWN_LOCK callers have to handle this in
1269 * their own manner. This is a further example of where the old
1270 * truncate sequence is inadequate.
1271 *
1272 * NOTE: filesystems with their own locking have to handle this
1273 * on their own.
1274 */
1275 if (flags & DIO_LOCKING) {
1276 if (unlikely((rw & WRITE) && retval < 0)) {
1277 loff_t isize = i_size_read(inode);
1278 loff_t end = offset + iov_length(iov, nr_segs);
1279
1280 if (end > isize)
1281 vmtruncate(inode, isize);
1282 }
1283 }
1284
1285 return retval;
1286}
1287EXPORT_SYMBOL(__blockdev_direct_IO); 1255EXPORT_SYMBOL(__blockdev_direct_IO);