From 6e68af666f5336254b5715dca591026b7324499a Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Fri, 11 Nov 2005 05:30:27 -0600 Subject: [SCSI] Convert SCSI mid-layer to scsi_execute_async Add scsi helpers to create really-large-requests and convert scsi-ml to scsi_execute_async(). Per Jens's previous comments, I placed this function in scsi_lib.c. I made it follow all the queue's limits - I think I did at least :), so I removed the warning on the function header. I think the scsi_execute_* functions should eventually take a request_queue and be placed some place where the dm-multipath hw_handler can use them if that failover code is going to stay in the kernel. That conversion patch will be sent in another mail though. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- fs/bio.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'fs') diff --git a/fs/bio.c b/fs/bio.c index 460554b..4d21ee3 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -386,6 +386,25 @@ static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page } /** + * bio_add_pc_page - attempt to add page to bio + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * + * Attempt to add a page to the bio_vec maplist. This can fail for a + * number of reasons, such as the bio being full or target block + * device limitations. The target block device must allow bio's + * smaller than PAGE_SIZE, so it is always possible to add a single + * page to an empty bio. This should only be used by REQ_PC bios. + */ +int bio_add_pc_page(request_queue_t *q, struct bio *bio, struct page *page, + unsigned int len, unsigned int offset) +{ + return __bio_add_page(q, bio, page, len, offset); +} + +/** * bio_add_page - attempt to add page to bio * @bio: destination bio * @page: page to add @@ -1228,6 +1247,7 @@ EXPORT_SYMBOL(bio_clone); EXPORT_SYMBOL(bio_phys_segments); EXPORT_SYMBOL(bio_hw_segments); EXPORT_SYMBOL(bio_add_page); +EXPORT_SYMBOL(bio_add_pc_page); EXPORT_SYMBOL(bio_get_nr_vecs); EXPORT_SYMBOL(bio_map_user); EXPORT_SYMBOL(bio_unmap_user); -- cgit v1.1 From defd94b75409b983f94548ea2f52ff5787ddb848 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Mon, 5 Dec 2005 02:37:06 -0600 Subject: [SCSI] seperate max_sectors from max_hw_sectors - export __blk_put_request and blk_execute_rq_nowait needed for async REQ_BLOCK_PC requests - seperate max_hw_sectors and max_sectors for block/scsi_ioctl.c and SG_IO bio.c helpers per Jens's last comments. Since block/scsi_ioctl.c SG_IO was already testing against max_sectors and SCSI-ml was setting max_sectors and max_hw_sectors to the same value this does not change any scsi SG_IO behavior. It only prepares ll_rw_blk.c, scsi_ioctl.c and bio.c for when SCSI-ml begins to set a valid max_hw_sectors for all LLDs. Today if a LLD does not set it SCSI-ml sets it to a safe default and some LLDs set it to a artificial low value to overcome memory and feedback issues. Note: Since we now cap max_sectors to BLK_DEF_MAX_SECTORS, which is 1024, drivers that used to call blk_queue_max_sectors with a large value of max_sectors will now see the fs requests capped to BLK_DEF_MAX_SECTORS. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- fs/bio.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) (limited to 'fs') diff --git a/fs/bio.c b/fs/bio.c index 4d21ee3..38d3e80 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -313,7 +313,8 @@ int bio_get_nr_vecs(struct block_device *bdev) } static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page - *page, unsigned int len, unsigned int offset) + *page, unsigned int len, unsigned int offset, + unsigned short max_sectors) { int retried_segments = 0; struct bio_vec *bvec; @@ -327,7 +328,7 @@ static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page if (bio->bi_vcnt >= bio->bi_max_vecs) return 0; - if (((bio->bi_size + len) >> 9) > q->max_sectors) + if (((bio->bi_size + len) >> 9) > max_sectors) return 0; /* @@ -401,7 +402,7 @@ static int __bio_add_page(request_queue_t *q, struct bio *bio, struct page int bio_add_pc_page(request_queue_t *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { - return __bio_add_page(q, bio, page, len, offset); + return __bio_add_page(q, bio, page, len, offset, q->max_hw_sectors); } /** @@ -420,8 +421,8 @@ int bio_add_pc_page(request_queue_t *q, struct bio *bio, struct page *page, int bio_add_page(struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { - return __bio_add_page(bdev_get_queue(bio->bi_bdev), bio, page, - len, offset); + struct request_queue *q = bdev_get_queue(bio->bi_bdev); + return __bio_add_page(q, bio, page, len, offset, q->max_sectors); } struct bio_map_data { @@ -533,7 +534,7 @@ struct bio *bio_copy_user(request_queue_t *q, unsigned long uaddr, break; } - if (__bio_add_page(q, bio, page, bytes, 0) < bytes) { + if (bio_add_pc_page(q, bio, page, bytes, 0) < bytes) { ret = -EINVAL; break; } @@ -647,7 +648,8 @@ static struct bio *__bio_map_user_iov(request_queue_t *q, /* * sorry... */ - if (__bio_add_page(q, bio, pages[j], bytes, offset) < bytes) + if (bio_add_pc_page(q, bio, pages[j], bytes, offset) < + bytes) break; len -= bytes; @@ -820,8 +822,8 @@ static struct bio *__bio_map_kern(request_queue_t *q, void *data, if (bytes > len) bytes = len; - if (__bio_add_page(q, bio, virt_to_page(data), bytes, - offset) < bytes) + if (bio_add_pc_page(q, bio, virt_to_page(data), bytes, + offset) < bytes) break; data += bytes; -- cgit v1.1