diff options
Diffstat (limited to 'fs/buffer.c')
| -rw-r--r-- | fs/buffer.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/fs/buffer.c b/fs/buffer.c index a0b70b3239f3..a6bc769e665d 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -3018,6 +3018,71 @@ int bh_uptodate_or_lock(struct buffer_head *bh) EXPORT_SYMBOL(bh_uptodate_or_lock); /** + * __bh_read - Submit read for a locked buffer + * @bh: struct buffer_head + * @op_flags: appending REQ_OP_* flags besides REQ_OP_READ + * @wait: wait until reading finish + * + * Returns zero on success or don't wait, and -EIO on error. + */ +int __bh_read(struct buffer_head *bh, blk_opf_t op_flags, bool wait) +{ + int ret = 0; + + BUG_ON(!buffer_locked(bh)); + + get_bh(bh); + bh->b_end_io = end_buffer_read_sync; + submit_bh(REQ_OP_READ | op_flags, bh); + if (wait) { + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) + ret = -EIO; + } + return ret; +} +EXPORT_SYMBOL(__bh_read); + +/** + * __bh_read_batch - Submit read for a batch of unlocked buffers + * @nr: entry number of the buffer batch + * @bhs: a batch of struct buffer_head + * @op_flags: appending REQ_OP_* flags besides REQ_OP_READ + * @force_lock: force to get a lock on the buffer if set, otherwise drops any + * buffer that cannot lock. + * + * Returns zero on success or don't wait, and -EIO on error. + */ +void __bh_read_batch(int nr, struct buffer_head *bhs[], + blk_opf_t op_flags, bool force_lock) +{ + int i; + + for (i = 0; i < nr; i++) { + struct buffer_head *bh = bhs[i]; + + if (buffer_uptodate(bh)) + continue; + + if (force_lock) + lock_buffer(bh); + else + if (!trylock_buffer(bh)) + continue; + + if (buffer_uptodate(bh)) { + unlock_buffer(bh); + continue; + } + + bh->b_end_io = end_buffer_read_sync; + get_bh(bh); + submit_bh(REQ_OP_READ | op_flags, bh); + } +} +EXPORT_SYMBOL(__bh_read_batch); + +/** * bh_submit_read - Submit a locked buffer for reading * @bh: struct buffer_head * |