X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fscsi%2Fscsi_lib.c;fp=drivers%2Fscsi%2Fscsi_lib.c;h=077c1c691210284428d416fb73392c89f1cdc92b;hb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;hp=faee4757c03adb712363eb09527c5af357c0bef3;hpb=4e76c8a9fa413ccc09d3f7f664183dcce3555d57;p=linux-2.6.git diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index faee4757c..077c1c691 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -19,18 +19,18 @@ #include #include +#include #include #include #include #include #include -#include #include "scsi_priv.h" #include "scsi_logging.h" -#define SG_MEMPOOL_NR (sizeof(scsi_sg_pools)/sizeof(struct scsi_host_sg_pool)) +#define SG_MEMPOOL_NR ARRAY_SIZE(scsi_sg_pools) #define SG_MEMPOOL_SIZE 32 struct scsi_host_sg_pool { @@ -83,7 +83,7 @@ static void scsi_unprep_request(struct request *req) struct scsi_cmnd *cmd = req->special; req->flags &= ~REQ_DONTPREP; - req->special = (req->flags & REQ_SPECIAL) ? cmd->sc_request : NULL; + req->special = NULL; scsi_put_command(cmd); } @@ -161,72 +161,6 @@ int scsi_queue_insert(struct scsi_cmnd *cmd, int reason) return 0; } -/* - * Function: scsi_do_req - * - * Purpose: Queue a SCSI request - * - * Arguments: sreq - command descriptor. - * cmnd - actual SCSI command to be performed. - * buffer - data buffer. - * bufflen - size of data buffer. - * done - completion function to be run. - * timeout - how long to let it run before timeout. - * retries - number of retries we allow. - * - * Lock status: No locks held upon entry. - * - * Returns: Nothing. - * - * Notes: This function is only used for queueing requests for things - * like ioctls and character device requests - this is because - * we essentially just inject a request into the queue for the - * device. - * - * In order to support the scsi_device_quiesce function, we - * now inject requests on the *head* of the device queue - * rather than the tail. - */ -void scsi_do_req(struct scsi_request *sreq, const void *cmnd, - void *buffer, unsigned bufflen, - void (*done)(struct scsi_cmnd *), - int timeout, int retries) -{ - /* - * If the upper level driver is reusing these things, then - * we should release the low-level block now. Another one will - * be allocated later when this request is getting queued. - */ - __scsi_release_request(sreq); - - /* - * Our own function scsi_done (which marks the host as not busy, - * disables the timeout counter, etc) will be called by us or by the - * scsi_hosts[host].queuecommand() function needs to also call - * the completion function for the high level driver. - */ - memcpy(sreq->sr_cmnd, cmnd, sizeof(sreq->sr_cmnd)); - sreq->sr_bufflen = bufflen; - sreq->sr_buffer = buffer; - sreq->sr_allowed = retries; - sreq->sr_done = done; - sreq->sr_timeout_per_command = timeout; - - if (sreq->sr_cmd_len == 0) - sreq->sr_cmd_len = COMMAND_SIZE(sreq->sr_cmnd[0]); - - /* - * 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 - */ - sreq->sr_request->flags &= ~REQ_DONTPREP; - blk_insert_request(sreq->sr_device->request_queue, sreq->sr_request, - 1, sreq); -} -EXPORT_SYMBOL(scsi_do_req); - /** * scsi_execute - insert request and wait for the result * @sdev: scsi device @@ -502,60 +436,16 @@ EXPORT_SYMBOL_GPL(scsi_execute_async); * * Arguments: cmd - command that is ready to be queued. * - * Returns: Nothing - * * Notes: This function has the job of initializing a number of * fields related to error handling. Typically this will * be called once for each command, as required. */ -static int scsi_init_cmd_errh(struct scsi_cmnd *cmd) +static void scsi_init_cmd_errh(struct scsi_cmnd *cmd) { cmd->serial_number = 0; - memset(cmd->sense_buffer, 0, sizeof cmd->sense_buffer); - if (cmd->cmd_len == 0) cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]); - - /* - * We need saved copies of a number of fields - this is because - * error handling may need to overwrite these with different values - * to run different commands, and once error handling is complete, - * we will need to restore these values prior to running the actual - * command. - */ - cmd->old_use_sg = cmd->use_sg; - cmd->old_cmd_len = cmd->cmd_len; - cmd->sc_old_data_direction = cmd->sc_data_direction; - cmd->old_underflow = cmd->underflow; - memcpy(cmd->data_cmnd, cmd->cmnd, sizeof(cmd->cmnd)); - cmd->buffer = cmd->request_buffer; - cmd->bufflen = cmd->request_bufflen; - - return 1; -} - -/* - * Function: scsi_setup_cmd_retry() - * - * Purpose: Restore the command state for a retry - * - * Arguments: cmd - command to be restored - * - * Returns: Nothing - * - * Notes: Immediately prior to retrying a command, we need - * to restore certain fields that we saved above. - */ -void scsi_setup_cmd_retry(struct scsi_cmnd *cmd) -{ - memcpy(cmd->cmnd, cmd->data_cmnd, sizeof(cmd->data_cmnd)); - cmd->request_buffer = cmd->buffer; - cmd->request_bufflen = cmd->bufflen; - cmd->use_sg = cmd->old_use_sg; - cmd->cmd_len = cmd->old_cmd_len; - cmd->sc_data_direction = cmd->sc_old_data_direction; - cmd->underflow = cmd->old_underflow; } void scsi_device_unbusy(struct scsi_device *sdev) @@ -566,7 +456,7 @@ void scsi_device_unbusy(struct scsi_device *sdev) spin_lock_irqsave(shost->host_lock, flags); shost->host_busy--; if (unlikely(scsi_host_in_recovery(shost) && - shost->host_failed)) + (shost->host_failed || shost->host_eh_scheduled))) scsi_eh_wakeup(shost); spin_unlock(shost->host_lock); spin_lock(sdev->request_queue->queue_lock); @@ -873,22 +763,13 @@ static void scsi_free_sgtable(struct scatterlist *sgl, int index) */ static void scsi_release_buffers(struct scsi_cmnd *cmd) { - struct request *req = cmd->request; - - /* - * Free up any indirection buffers we allocated for DMA purposes. - */ if (cmd->use_sg) scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len); - else if (cmd->request_buffer != req->buffer) - kfree(cmd->request_buffer); /* * Zero these out. They now point to freed memory, and it is * dangerous to hang onto the pointers. */ - cmd->buffer = NULL; - cmd->bufflen = 0; cmd->request_buffer = NULL; cmd->request_bufflen = 0; } @@ -921,11 +802,10 @@ static void scsi_release_buffers(struct scsi_cmnd *cmd) * b) We can just use scsi_requeue_command() here. This would * be used if we just wanted to retry, for example. */ -void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, - unsigned int block_bytes) +void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) { int result = cmd->result; - int this_count = cmd->bufflen; + int this_count = cmd->request_bufflen; request_queue_t *q = cmd->device->request_queue; struct request *req = cmd->request; int clear_errors = 1; @@ -933,28 +813,14 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, int sense_valid = 0; int sense_deferred = 0; - /* - * Free up any indirection buffers we allocated for DMA purposes. - * For the case of a READ, we need to copy the data out of the - * bounce buffer and into the real buffer. - */ - if (cmd->use_sg) - scsi_free_sgtable(cmd->buffer, cmd->sglist_len); - else if (cmd->buffer != req->buffer) { - if (rq_data_dir(req) == READ) { - unsigned long flags; - char *to = bio_kmap_irq(req->bio, &flags); - memcpy(to, cmd->buffer, cmd->bufflen); - bio_kunmap_irq(to, &flags); - } - kfree(cmd->buffer); - } + scsi_release_buffers(cmd); if (result) { sense_valid = scsi_command_normalize_sense(cmd, &sshdr); if (sense_valid) sense_deferred = scsi_sense_is_deferred(&sshdr); } + if (blk_pc_request(req)) { /* SG_IO ioctl from block level */ req->errors = result; if (result) { @@ -974,100 +840,74 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, req->data_len = cmd->resid; } - /* - * Zero these out. They now point to freed memory, and it is - * dangerous to hang onto the pointers. - */ - cmd->buffer = NULL; - cmd->bufflen = 0; - cmd->request_buffer = NULL; - cmd->request_bufflen = 0; - /* * Next deal with any sectors which we were able to correctly * handle. */ - if (good_bytes >= 0) { - SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, %d bytes done.\n", - req->nr_sectors, good_bytes)); - SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg)); + SCSI_LOG_HLCOMPLETE(1, printk("%ld sectors total, " + "%d bytes done.\n", + req->nr_sectors, good_bytes)); + SCSI_LOG_HLCOMPLETE(1, printk("use_sg is %d\n", cmd->use_sg)); - if (clear_errors) - req->errors = 0; - /* - * If multiple sectors are requested in one buffer, then - * they will have been finished off by the first command. - * If not, then we have a multi-buffer command. - * - * If block_bytes != 0, it means we had a medium error - * of some sort, and that we want to mark some number of - * sectors as not uptodate. Thus we want to inhibit - * requeueing right here - we will requeue down below - * when we handle the bad sectors. - */ + if (clear_errors) + req->errors = 0; - /* - * If the command completed without error, then either - * finish off the rest of the command, or start a new one. - */ - if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL) - return; - } - /* - * Now, if we were good little boys and girls, Santa left us a request - * sense buffer. We can extract information from this, so we - * can choose a block to remap, etc. + /* A number of bytes were successfully read. If there + * are leftovers and there is some kind of error + * (result != 0), retry the rest. + */ + if (scsi_end_request(cmd, 1, good_bytes, result == 0) == NULL) + return; + + /* good_bytes = 0, or (inclusive) there were leftovers and + * result = 0, so scsi_end_request couldn't retry. */ if (sense_valid && !sense_deferred) { switch (sshdr.sense_key) { case UNIT_ATTENTION: if (cmd->device->removable) { - /* detected disc change. set a bit + /* Detected disc change. Set a bit * and quietly refuse further access. */ cmd->device->changed = 1; - scsi_end_request(cmd, 0, - this_count, 1); + scsi_end_request(cmd, 0, this_count, 1); return; } else { - /* - * Must have been a power glitch, or a - * bus reset. Could not have been a - * media change, so we just retry the - * request and see what happens. - */ + /* Must have been a power glitch, or a + * bus reset. Could not have been a + * media change, so we just retry the + * request and see what happens. + */ scsi_requeue_command(q, cmd); return; } break; case ILLEGAL_REQUEST: - /* - * If we had an ILLEGAL REQUEST returned, then we may - * have performed an unsupported command. The only - * thing this should be would be a ten byte read where - * only a six byte read was supported. Also, on a - * system where READ CAPACITY failed, we may have read - * past the end of the disk. - */ + /* If we had an ILLEGAL REQUEST returned, then + * we may have performed an unsupported + * command. The only thing this should be + * would be a ten byte read where only a six + * byte read was supported. Also, on a system + * where READ CAPACITY failed, we may have + * read past the end of the disk. + */ if ((cmd->device->use_10_for_rw && sshdr.asc == 0x20 && sshdr.ascq == 0x00) && (cmd->cmnd[0] == READ_10 || cmd->cmnd[0] == WRITE_10)) { cmd->device->use_10_for_rw = 0; - /* - * This will cause a retry with a 6-byte - * command. + /* This will cause a retry with a + * 6-byte command. */ scsi_requeue_command(q, cmd); - result = 0; + return; } else { scsi_end_request(cmd, 0, this_count, 1); return; } break; case NOT_READY: - /* - * If the device is in the process of becoming + /* If the device is in the process of becoming * ready, or has a temporary blockage, retry. */ if (sshdr.asc == 0x04) { @@ -1087,7 +927,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, } if (!(req->flags & REQ_QUIET)) { scmd_printk(KERN_INFO, cmd, - "Device not ready: "); + "Device not ready: "); scsi_print_sense_hdr("", &sshdr); } scsi_end_request(cmd, 0, this_count, 1); @@ -1095,21 +935,21 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, case VOLUME_OVERFLOW: if (!(req->flags & REQ_QUIET)) { scmd_printk(KERN_INFO, cmd, - "Volume overflow, CDB: "); - __scsi_print_command(cmd->data_cmnd); + "Volume overflow, CDB: "); + __scsi_print_command(cmd->cmnd); scsi_print_sense("", cmd); } - scsi_end_request(cmd, 0, block_bytes, 1); + /* See SSC3rXX or current. */ + scsi_end_request(cmd, 0, this_count, 1); return; default: break; } - } /* driver byte != 0 */ + } if (host_byte(result) == DID_RESET) { - /* - * Third party bus reset or reset for error - * recovery reasons. Just retry the request - * and see what happens. + /* Third party bus reset or reset for error recovery + * reasons. Just retry the request and see what + * happens. */ scsi_requeue_command(q, cmd); return; @@ -1117,21 +957,13 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes, if (result) { if (!(req->flags & REQ_QUIET)) { scmd_printk(KERN_INFO, cmd, - "SCSI error: return code = 0x%x\n", result); - + "SCSI error: return code = 0x%08x\n", + result); if (driver_byte(result) & DRIVER_SENSE) scsi_print_sense("", cmd); } - /* - * Mark a single buffer as not uptodate. Queue the remainder. - * We sometimes get this cruft in the event that a medium error - * isn't properly reported. - */ - block_bytes = req->hard_cur_sectors << 9; - if (!block_bytes) - block_bytes = req->data_len; - scsi_end_request(cmd, 0, block_bytes, 1); } + scsi_end_request(cmd, 0, this_count, !result); } EXPORT_SYMBOL(scsi_io_completion); @@ -1235,7 +1067,7 @@ static void scsi_blk_pc_done(struct scsi_cmnd *cmd) * successfully. Since this is a REQ_BLOCK_PC command the * caller should check the request's errors value */ - scsi_io_completion(cmd, cmd->bufflen, 0); + scsi_io_completion(cmd, cmd->request_bufflen); } static void scsi_setup_blk_pc_cmnd(struct scsi_cmnd *cmd) @@ -1300,15 +1132,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req) * at request->cmd, as this tells us the real story. */ if (req->flags & REQ_SPECIAL && req->special) { - struct scsi_request *sreq = req->special; - - if (sreq->sr_magic == SCSI_REQ_MAGIC) { - cmd = scsi_get_command(sreq->sr_device, GFP_ATOMIC); - if (unlikely(!cmd)) - goto defer; - scsi_init_cmd_from_req(cmd, sreq); - } else - cmd = req->special; + cmd = req->special; } else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) { if(unlikely(specials_only) && !(req->flags & REQ_SPECIAL)) { @@ -2124,6 +1948,7 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) switch (oldstate) { case SDEV_CREATED: case SDEV_RUNNING: + case SDEV_QUIESCE: case SDEV_OFFLINE: case SDEV_BLOCK: break; @@ -2134,6 +1959,9 @@ scsi_device_set_state(struct scsi_device *sdev, enum scsi_device_state state) case SDEV_DEL: switch (oldstate) { + case SDEV_CREATED: + case SDEV_RUNNING: + case SDEV_OFFLINE: case SDEV_CANCEL: break; default: @@ -2363,3 +2191,61 @@ scsi_target_unblock(struct device *dev) device_for_each_child(dev, NULL, target_unblock); } EXPORT_SYMBOL_GPL(scsi_target_unblock); + +/** + * scsi_kmap_atomic_sg - find and atomically map an sg-elemnt + * @sg: scatter-gather list + * @sg_count: number of segments in sg + * @offset: offset in bytes into sg, on return offset into the mapped area + * @len: bytes to map, on return number of bytes mapped + * + * Returns virtual address of the start of the mapped page + */ +void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count, + size_t *offset, size_t *len) +{ + int i; + size_t sg_len = 0, len_complete = 0; + struct page *page; + + for (i = 0; i < sg_count; i++) { + len_complete = sg_len; /* Complete sg-entries */ + sg_len += sg[i].length; + if (sg_len > *offset) + break; + } + + if (unlikely(i == sg_count)) { + printk(KERN_ERR "%s: Bytes in sg: %zu, requested offset %zu, " + "elements %d\n", + __FUNCTION__, sg_len, *offset, sg_count); + WARN_ON(1); + return NULL; + } + + /* Offset starting from the beginning of first page in this sg-entry */ + *offset = *offset - len_complete + sg[i].offset; + + /* Assumption: contiguous pages can be accessed as "page + i" */ + page = nth_page(sg[i].page, (*offset >> PAGE_SHIFT)); + *offset &= ~PAGE_MASK; + + /* Bytes in this sg-entry from *offset to the end of the page */ + sg_len = PAGE_SIZE - *offset; + if (*len > sg_len) + *len = sg_len; + + return kmap_atomic(page, KM_BIO_SRC_IRQ); +} +EXPORT_SYMBOL(scsi_kmap_atomic_sg); + +/** + * scsi_kunmap_atomic_sg - atomically unmap a virtual address, previously + * mapped with scsi_kmap_atomic_sg + * @virt: virtual address to be unmapped + */ +void scsi_kunmap_atomic_sg(void *virt) +{ + kunmap_atomic(virt, KM_BIO_SRC_IRQ); +} +EXPORT_SYMBOL(scsi_kunmap_atomic_sg);