diff options
| -rw-r--r-- | drivers/md/dm-bufio.c | 69 | ||||
| -rw-r--r-- | include/linux/dm-bufio.h | 12 |
2 files changed, 76 insertions, 5 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index 2d519c223562..bf289be1ee3a 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -631,6 +631,19 @@ dmio: submit_bio(bio); } +static inline sector_t block_to_sector(struct dm_bufio_client *c, sector_t block) +{ + sector_t sector; + + if (likely(c->sectors_per_block_bits >= 0)) + sector = block << c->sectors_per_block_bits; + else + sector = block * (c->block_size >> SECTOR_SHIFT); + sector += c->start; + + return sector; +} + static void submit_io(struct dm_buffer *b, int rw, void (*end_io)(struct dm_buffer *, blk_status_t)) { unsigned n_sectors; @@ -639,11 +652,7 @@ static void submit_io(struct dm_buffer *b, int rw, void (*end_io)(struct dm_buff b->end_io = end_io; - if (likely(b->c->sectors_per_block_bits >= 0)) - sector = b->block << b->c->sectors_per_block_bits; - else - sector = b->block * (b->c->block_size >> SECTOR_SHIFT); - sector += b->c->start; + sector = block_to_sector(b->c, b->block); if (rw != REQ_OP_WRITE) { n_sectors = b->c->block_size >> SECTOR_SHIFT; @@ -1326,6 +1335,56 @@ int dm_bufio_issue_flush(struct dm_bufio_client *c) EXPORT_SYMBOL_GPL(dm_bufio_issue_flush); /* + * Use dm-io to send a discard request to flush the device. + */ +int dm_bufio_issue_discard(struct dm_bufio_client *c, sector_t block, sector_t count) +{ + struct dm_io_request io_req = { + .bi_op = REQ_OP_DISCARD, + .bi_op_flags = REQ_SYNC, + .mem.type = DM_IO_KMEM, + .mem.ptr.addr = NULL, + .client = c->dm_io, + }; + struct dm_io_region io_reg = { + .bdev = c->bdev, + .sector = block_to_sector(c, block), + .count = block_to_sector(c, count), + }; + + BUG_ON(dm_bufio_in_request()); + + return dm_io(&io_req, 1, &io_reg, NULL); +} +EXPORT_SYMBOL_GPL(dm_bufio_issue_discard); + +/* + * Free the specified range of buffers. If a buffer is held by other process, it + * is not freed. If a buffer is dirty, it is discarded without writeback. + * Finally, send the discard request to the device. + */ +int dm_bufio_discard_buffers(struct dm_bufio_client *c, sector_t block, sector_t count) +{ + sector_t i; + + for (i = block; i < block + count; i++) { + struct dm_buffer *b; + dm_bufio_lock(c); + b = __find(c, i); + if (b && likely(!b->hold_count)) { + wait_on_bit_io(&b->state, B_READING, TASK_UNINTERRUPTIBLE); + wait_on_bit_io(&b->state, B_WRITING, TASK_UNINTERRUPTIBLE); + __unlink_buffer(b); + __free_buffer_wake(b); + } + dm_bufio_unlock(c); + } + + return dm_bufio_issue_discard(c, block, count); +} +EXPORT_SYMBOL_GPL(dm_bufio_discard_buffers); + +/* * We first delete any other buffer that may be at that new location. * * Then, we write the buffer to the original location if it was dirty. diff --git a/include/linux/dm-bufio.h b/include/linux/dm-bufio.h index 3c8b7d274bd9..07e1f163e299 100644 --- a/include/linux/dm-bufio.h +++ b/include/linux/dm-bufio.h @@ -119,6 +119,18 @@ int dm_bufio_write_dirty_buffers(struct dm_bufio_client *c); int dm_bufio_issue_flush(struct dm_bufio_client *c); /* + * Send a discard request to the underlying device. + */ +int dm_bufio_issue_discard(struct dm_bufio_client *c, sector_t block, sector_t count); + +/* + * Free the specified range of buffers. If a buffer is held by other process, it + * is not freed. If a buffer is dirty, it is discarded without writeback. + * Finally, send the discard request to the device. + */ +int dm_bufio_discard_buffers(struct dm_bufio_client *c, sector_t block, sector_t count); + +/* * Like dm_bufio_release but also move the buffer to the new * block. dm_bufio_write_dirty_buffers is needed to commit the new block. */ |