diff options
| -rw-r--r-- | drivers/scsi/scsi_error.c | 47 | ||||
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 230 | ||||
| -rw-r--r-- | drivers/scsi/scsi_priv.h | 1 | ||||
| -rw-r--r-- | fs/bio.c | 20 | ||||
| -rw-r--r-- | include/linux/bio.h | 2 | ||||
| -rw-r--r-- | include/scsi/scsi_device.h | 6 |
6 files changed, 233 insertions, 73 deletions
diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 18c5d2523014..53ea62d3b53d 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -1315,23 +1315,6 @@ int scsi_decide_disposition(struct scsi_cmnd *scmd) } /** - * scsi_eh_lock_done - done function for eh door lock request - * @scmd: SCSI command block for the door lock request - * - * Notes: - * We completed the asynchronous door lock request, and it has either - * locked the door or failed. We must free the command structures - * associated with this request. - **/ -static void scsi_eh_lock_done(struct scsi_cmnd *scmd) -{ - struct scsi_request *sreq = scmd->sc_request; - - scsi_release_request(sreq); -} - - -/** * scsi_eh_lock_door - Prevent medium removal for the specified device * @sdev: SCSI device to prevent medium removal * @@ -1353,29 +1336,17 @@ static void scsi_eh_lock_done(struct scsi_cmnd *scmd) **/ static void scsi_eh_lock_door(struct scsi_device *sdev) { - struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL); + unsigned char cmnd[MAX_COMMAND_SIZE]; - if (unlikely(!sreq)) { - printk(KERN_ERR "%s: request allocate failed," - "prevent media removal cmd not sent\n", __FUNCTION__); - return; - } + cmnd[0] = ALLOW_MEDIUM_REMOVAL; + cmnd[1] = 0; + cmnd[2] = 0; + cmnd[3] = 0; + cmnd[4] = SCSI_REMOVAL_PREVENT; + cmnd[5] = 0; - sreq->sr_cmnd[0] = ALLOW_MEDIUM_REMOVAL; - sreq->sr_cmnd[1] = 0; - sreq->sr_cmnd[2] = 0; - sreq->sr_cmnd[3] = 0; - sreq->sr_cmnd[4] = SCSI_REMOVAL_PREVENT; - sreq->sr_cmnd[5] = 0; - sreq->sr_data_direction = DMA_NONE; - sreq->sr_bufflen = 0; - sreq->sr_buffer = NULL; - sreq->sr_allowed = 5; - sreq->sr_done = scsi_eh_lock_done; - sreq->sr_timeout_per_command = 10 * HZ; - sreq->sr_cmd_len = COMMAND_SIZE(sreq->sr_cmnd[0]); - - scsi_insert_special_req(sreq, 1); + scsi_execute_async(sdev, cmnd, DMA_NONE, NULL, 0, 0, 10 * HZ, + 5, NULL, NULL, GFP_KERNEL); } diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 1f2782767ca9..eb0cfbfbcf8f 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -63,39 +63,6 @@ static struct scsi_host_sg_pool scsi_sg_pools[] = { }; #undef SP - -/* - * Function: scsi_insert_special_req() - * - * Purpose: Insert pre-formed request into request queue. - * - * Arguments: sreq - request that is ready to be queued. - * at_head - boolean. True if we should insert at head - * of queue, false if we should insert at tail. - * - * Lock status: Assumed that lock is not held upon entry. - * - * Returns: Nothing - * - * Notes: This function is called from character device and from - * ioctl types of functions where the caller knows exactly - * what SCSI command needs to be issued. The idea is that - * we merely inject the command into the queue (at the head - * for now), and then call the queue request function to actually - * process it. - */ -int scsi_insert_special_req(struct scsi_request *sreq, int at_head) -{ - /* - * Because users of this function are apt to reuse requests with no - * modification, we have to sanitise the request flags here - */ - sreq->sr_request->flags &= ~REQ_DONTPREP; - blk_insert_request(sreq->sr_device->request_queue, sreq->sr_request, - at_head, sreq); - return 0; -} - static void scsi_run_queue(struct request_queue *q); /* @@ -249,8 +216,13 @@ void scsi_do_req(struct scsi_request *sreq, const void *cmnd, /* * head injection *required* here otherwise quiesce won't work + * + * Because users of this function are apt to reuse requests with no + * modification, we have to sanitise the request flags here */ - scsi_insert_special_req(sreq, 1); + sreq->sr_request->flags &= ~REQ_DONTPREP; + blk_insert_request(sreq->sr_device->request_queue, sreq->sr_request, + 1, sreq); } EXPORT_SYMBOL(scsi_do_req); @@ -327,6 +299,196 @@ int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd, } EXPORT_SYMBOL(scsi_execute_req); +struct scsi_io_context { + void *data; + void (*done)(void *data, char *sense, int result, int resid); + char sense[SCSI_SENSE_BUFFERSIZE]; +}; + +static void scsi_end_async(struct request *req) +{ + struct scsi_io_context *sioc = req->end_io_data; + + if (sioc->done) + sioc->done(sioc->data, sioc->sense, req->errors, req->data_len); + + kfree(sioc); + __blk_put_request(req->q, req); +} + +static int scsi_merge_bio(struct request *rq, struct bio *bio) +{ + struct request_queue *q = rq->q; + + bio->bi_flags &= ~(1 << BIO_SEG_VALID); + if (rq_data_dir(rq) == WRITE) + bio->bi_rw |= (1 << BIO_RW); + blk_queue_bounce(q, &bio); + + if (!rq->bio) + blk_rq_bio_prep(q, rq, bio); + else if (!q->back_merge_fn(q, rq, bio)) + return -EINVAL; + else { + rq->biotail->bi_next = bio; + rq->biotail = bio; + rq->hard_nr_sectors += bio_sectors(bio); + rq->nr_sectors = rq->hard_nr_sectors; + } + + return 0; +} + +static int scsi_bi_endio(struct bio *bio, unsigned int bytes_done, int error) +{ + if (bio->bi_size) + return 1; + + bio_put(bio); + return 0; +} + +/** + * scsi_req_map_sg - map a scatterlist into a request + * @rq: request to fill + * @sg: scatterlist + * @nsegs: number of elements + * @bufflen: len of buffer + * @gfp: memory allocation flags + * + * scsi_req_map_sg maps a scatterlist into a request so that the + * request can be sent to the block layer. We do not trust the scatterlist + * sent to use, as some ULDs use that struct to only organize the pages. + */ +static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl, + int nsegs, unsigned bufflen, gfp_t gfp) +{ + struct request_queue *q = rq->q; + int nr_pages = (bufflen + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned int data_len = 0, len, bytes, off; + struct page *page; + struct bio *bio = NULL; + int i, err, nr_vecs = 0; + + for (i = 0; i < nsegs; i++) { + page = sgl[i].page; + off = sgl[i].offset; + len = sgl[i].length; + data_len += len; + + while (len > 0) { + bytes = min_t(unsigned int, len, PAGE_SIZE - off); + + if (!bio) { + nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages); + nr_pages -= nr_vecs; + + bio = bio_alloc(gfp, nr_vecs); + if (!bio) { + err = -ENOMEM; + goto free_bios; + } + bio->bi_end_io = scsi_bi_endio; + } + + if (bio_add_pc_page(q, bio, page, bytes, off) != + bytes) { + bio_put(bio); + err = -EINVAL; + goto free_bios; + } + + if (bio->bi_vcnt >= nr_vecs) { + err = scsi_merge_bio(rq, bio); + if (err) { + bio_endio(bio, bio->bi_size, 0); + goto free_bios; + } + bio = NULL; + } + + page++; + len -= bytes; + off = 0; + } + } + + rq->buffer = rq->data = NULL; + rq->data_len = data_len; + return 0; + +free_bios: + while ((bio = rq->bio) != NULL) { + rq->bio = bio->bi_next; + /* + * call endio instead of bio_put incase it was bounced + */ + bio_endio(bio, bio->bi_size, 0); + } + + return err; +} + +/** + * scsi_execute_async - insert request + * @sdev: scsi device + * @cmd: scsi command + * @data_direction: data direction + * @buffer: data buffer (this can be a kernel buffer or scatterlist) + * @bufflen: len of buffer + * @use_sg: if buffer is a scatterlist this is the number of elements + * @timeout: request timeout in seconds + * @retries: number of times to retry request + * @flags: or into request flags + **/ +int scsi_execute_async(struct scsi_device *sdev, const unsigned char *cmd, + int data_direction, void *buffer, unsigned bufflen, + int use_sg, int timeout, int retries, void *privdata, + void (*done)(void *, char *, int, int), gfp_t gfp) +{ + struct request *req; + struct scsi_io_context *sioc; + int err = 0; + int write = (data_direction == DMA_TO_DEVICE); + + sioc = kzalloc(sizeof(*sioc), gfp); + if (!sioc) + return DRIVER_ERROR << 24; + + req = blk_get_request(sdev->request_queue, write, gfp); + if (!req) + goto free_sense; + + if (use_sg) + err = scsi_req_map_sg(req, buffer, use_sg, bufflen, gfp); + else if (bufflen) + err = blk_rq_map_kern(req->q, req, buffer, bufflen, gfp); + + if (err) + goto free_req; + + req->cmd_len = COMMAND_SIZE(cmd[0]); + memcpy(req->cmd, cmd, req->cmd_len); + req->sense = sioc->sense; + req->sense_len = 0; + req->timeout = timeout; + req->flags |= REQ_BLOCK_PC | REQ_QUIET; + req->end_io_data = sioc; + + sioc->data = privdata; + sioc->done = done; + + blk_execute_rq_nowait(req->q, NULL, req, 1, scsi_end_async); + return 0; + +free_req: + blk_put_request(req); +free_sense: + kfree(sioc); + return DRIVER_ERROR << 24; +} +EXPORT_SYMBOL_GPL(scsi_execute_async); + /* * Function: scsi_init_cmd_errh() * diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h index a8d121c8fbcd..f04e7e11f57a 100644 --- a/drivers/scsi/scsi_priv.h +++ b/drivers/scsi/scsi_priv.h @@ -40,7 +40,6 @@ extern void scsi_exit_hosts(void); extern int scsi_dispatch_cmd(struct scsi_cmnd *cmd); extern int scsi_setup_command_freelist(struct Scsi_Host *shost); extern void scsi_destroy_command_freelist(struct Scsi_Host *shost); -extern int scsi_insert_special_req(struct scsi_request *sreq, int); extern void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, struct scsi_request *sreq); extern void __scsi_release_request(struct scsi_request *sreq); @@ -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); diff --git a/include/linux/bio.h b/include/linux/bio.h index 685fd3720df5..b60ffe32cd21 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -292,6 +292,8 @@ extern struct bio *bio_clone(struct bio *, gfp_t); extern void bio_init(struct bio *); extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); +extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, + unsigned int, unsigned int); extern int bio_get_nr_vecs(struct block_device *); extern struct bio *bio_map_user(struct request_queue *, struct block_device *, unsigned long, unsigned int, int); diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 063e32fe036c..e94ca4d36035 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -274,6 +274,12 @@ extern int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd, extern int scsi_execute_req(struct scsi_device *sdev, const unsigned char *cmd, int data_direction, void *buffer, unsigned bufflen, struct scsi_sense_hdr *, int timeout, int retries); +extern int scsi_execute_async(struct scsi_device *sdev, + const unsigned char *cmd, int data_direction, + void *buffer, unsigned bufflen, int use_sg, + int timeout, int retries, void *privdata, + void (*done)(void *, char *, int, int), + gfp_t gfp); static inline unsigned int sdev_channel(struct scsi_device *sdev) { |