From: Webb Scales Date: Thu, 23 Apr 2015 14:35:04 +0000 (-0500) Subject: hpsa: use block layer tag for command allocation X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=73153fe533bc6209802521fc62d3e3648581a121;p=linux-beck.git hpsa: use block layer tag for command allocation Rework slave allocation: - separate the tagging support setup from the hostdata setup - make the hostdata setup act consistently when the lookup fails - make the hostdata setup act consistently when the device is not added - set up the queue depth consistently across these scenarios - if the block layer mq support is not available, explicitly enable and activate the SCSI layer tcq support (and do this at allocation-time so that the tags will be available for INQUIRY commands) Tweak slave configuration so that devices which are masked are also not attached. Reviewed-by: Scott Teel Reviewed-by: Kevin Barnett Reviewed-by: Tomas Henzl Reviewed-by: Hannes Reinecke Signed-off-by: Webb Scales Signed-off-by: Don Brace Reviewed-by: Christoph Hellwig Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index be837785b040..6fed6d88d7e4 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -44,6 +44,7 @@ #include #include #include +#include #include #include #include @@ -212,6 +213,9 @@ static int hpsa_compat_ioctl(struct scsi_device *dev, int cmd, static void cmd_free(struct ctlr_info *h, struct CommandList *c); static struct CommandList *cmd_alloc(struct ctlr_info *h); +static void cmd_tagged_free(struct ctlr_info *h, struct CommandList *c); +static struct CommandList *cmd_tagged_alloc(struct ctlr_info *h, + struct scsi_cmnd *scmd); static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h, void *buff, size_t size, u16 page_code, unsigned char *scsi3addr, int cmd_type); @@ -2010,11 +2014,17 @@ static void hpsa_cmd_resolve_events(struct ctlr_info *h, } } +static void hpsa_cmd_resolve_and_free(struct ctlr_info *h, + struct CommandList *c) +{ + hpsa_cmd_resolve_events(h, c); + cmd_tagged_free(h, c); +} + static void hpsa_cmd_free_and_done(struct ctlr_info *h, struct CommandList *c, struct scsi_cmnd *cmd) { - hpsa_cmd_resolve_events(h, c); - cmd_free(h, c); + hpsa_cmd_resolve_and_free(h, c); cmd->scsi_done(cmd); } @@ -2035,8 +2045,7 @@ static void hpsa_cmd_abort_and_free(struct ctlr_info *h, struct CommandList *c, hpsa_set_scsi_cmd_aborted(cmd); dev_warn(&h->pdev->dev, "CDB %16phN was aborted with status 0x%x\n", c->Request.CDB, c->err_info->ScsiStatus); - hpsa_cmd_resolve_events(h, c); - cmd_free(h, c); /* FIX-ME: change to cmd_tagged_free(h, c) */ + hpsa_cmd_resolve_and_free(h, c); } static void process_ioaccel2_completion(struct ctlr_info *h, @@ -4500,7 +4509,7 @@ static int hpsa_ciss_submit(struct ctlr_info *h, } if (hpsa_scatter_gather(h, c, cmd) < 0) { /* Fill SG list */ - cmd_free(h, c); + hpsa_cmd_resolve_and_free(h, c); return SCSI_MLQUEUE_HOST_BUSY; } enqueue_cmd_and_start_io(h, c); @@ -4546,6 +4555,8 @@ static inline void hpsa_cmd_partial_init(struct ctlr_info *h, int index, { dma_addr_t cmd_dma_handle = h->cmd_pool_dhandle + index * sizeof(*c); + BUG_ON(c->cmdindex != index); + memset(c->Request.CDB, 0, sizeof(c->Request.CDB)); memset(c->err_info, 0, sizeof(*c->err_info)); c->busaddr = (u32) cmd_dma_handle; @@ -4640,27 +4651,24 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) /* Get the ptr to our adapter structure out of cmd->host. */ h = sdev_to_hba(cmd->device); + + BUG_ON(cmd->request->tag < 0); + dev = cmd->device->hostdata; if (!dev) { cmd->result = DID_NO_CONNECT << 16; cmd->scsi_done(cmd); return 0; } - memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr)); - if (unlikely(lockup_detected(h))) { - cmd->result = DID_NO_CONNECT << 16; - cmd->scsi_done(cmd); - return 0; - } - c = cmd_alloc(h); + memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr)); if (unlikely(lockup_detected(h))) { cmd->result = DID_NO_CONNECT << 16; - cmd_free(h, c); cmd->scsi_done(cmd); return 0; } + c = cmd_tagged_alloc(h, cmd); /* * Call alternate submit routine for I/O accelerated commands. @@ -4673,7 +4681,7 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) if (rc == 0) return 0; if (rc == SCSI_MLQUEUE_HOST_BUSY) { - cmd_free(h, c); + hpsa_cmd_resolve_and_free(h, c); return SCSI_MLQUEUE_HOST_BUSY; } } @@ -4787,15 +4795,23 @@ static int hpsa_register_scsi(struct ctlr_info *h) sh->hostdata[0] = (unsigned long) h; sh->irq = h->intr[h->intr_mode]; sh->unique_id = sh->irq; + error = scsi_init_shared_tag_map(sh, sh->can_queue); + if (error) { + dev_err(&h->pdev->dev, + "%s: scsi_init_shared_tag_map failed for controller %d\n", + __func__, h->ctlr); + goto fail_host_put; + } error = scsi_add_host(sh, &h->pdev->dev); - if (error) + if (error) { + dev_err(&h->pdev->dev, "%s: scsi_add_host failed for controller %d\n", + __func__, h->ctlr); goto fail_host_put; + } scsi_scan_host(sh); return 0; fail_host_put: - dev_err(&h->pdev->dev, "%s: scsi_add_host" - " failed for controller %d\n", __func__, h->ctlr); scsi_host_put(sh); return error; fail: @@ -4804,6 +4820,23 @@ static int hpsa_register_scsi(struct ctlr_info *h) return -ENOMEM; } +/* + * The block layer has already gone to the trouble of picking out a unique, + * small-integer tag for this request. We use an offset from that value as + * an index to select our command block. (The offset allows us to reserve the + * low-numbered entries for our own uses.) + */ +static int hpsa_get_cmd_index(struct scsi_cmnd *scmd) +{ + int idx = scmd->request->tag; + + if (idx < 0) + return idx; + + /* Offset to leave space for internal cmds. */ + return idx += HPSA_NRESERVED_CMDS; +} + /* * Send a TEST_UNIT_READY command to the specified LUN using the specified * reply queue; returns zero if the unit is ready, and non-zero otherwise. @@ -4925,6 +4958,7 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd) int rc; struct ctlr_info *h; struct hpsa_scsi_dev_t *dev; + char msg[40]; /* find the controller to which the command to be aborted was sent */ h = sdev_to_hba(scsicmd->device); @@ -4943,19 +4977,17 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd) /* if controller locked up, we can guarantee command won't complete */ if (lockup_detected(h)) { - dev_warn(&h->pdev->dev, - "scsi %d:%d:%d:%d RESET FAILED, lockup detected\n", - h->scsi_host->host_no, dev->bus, dev->target, - dev->lun); + sprintf(msg, "cmd %d RESET FAILED, lockup detected", + hpsa_get_cmd_index(scsicmd)); + hpsa_show_dev_msg(KERN_WARNING, h, dev, msg); return FAILED; } /* this reset request might be the result of a lockup; check */ if (detect_controller_lockup(h)) { - dev_warn(&h->pdev->dev, - "scsi %d:%d:%d:%d RESET FAILED, new lockup detected\n", - h->scsi_host->host_no, dev->bus, dev->target, - dev->lun); + sprintf(msg, "cmd %d RESET FAILED, new lockup detected", + hpsa_get_cmd_index(scsicmd)); + hpsa_show_dev_msg(KERN_WARNING, h, dev, msg); return FAILED; } @@ -5398,6 +5430,58 @@ static int hpsa_eh_abort_handler(struct scsi_cmnd *sc) return !lockup_detected(h) ? SUCCESS : FAILED; } +/* + * For operations with an associated SCSI command, a command block is allocated + * at init, and managed by cmd_tagged_alloc() and cmd_tagged_free() using the + * block request tag as an index into a table of entries. cmd_tagged_free() is + * the complement, although cmd_free() may be called instead. + */ +static struct CommandList *cmd_tagged_alloc(struct ctlr_info *h, + struct scsi_cmnd *scmd) +{ + int idx = hpsa_get_cmd_index(scmd); + struct CommandList *c = h->cmd_pool + idx; + + if (idx < HPSA_NRESERVED_CMDS || idx >= h->nr_cmds) { + dev_err(&h->pdev->dev, "Bad block tag: %d not in [%d..%d]\n", + idx, HPSA_NRESERVED_CMDS, h->nr_cmds - 1); + /* The index value comes from the block layer, so if it's out of + * bounds, it's probably not our bug. + */ + BUG(); + } + + atomic_inc(&c->refcount); + if (unlikely(!hpsa_is_cmd_idle(c))) { + /* + * We expect that the SCSI layer will hand us a unique tag + * value. Thus, there should never be a collision here between + * two requests...because if the selected command isn't idle + * then someone is going to be very disappointed. + */ + dev_err(&h->pdev->dev, + "tag collision (tag=%d) in cmd_tagged_alloc().\n", + idx); + if (c->scsi_cmd != NULL) + scsi_print_command(c->scsi_cmd); + scsi_print_command(scmd); + } + + hpsa_cmd_partial_init(h, idx, c); + return c; +} + +static void cmd_tagged_free(struct ctlr_info *h, struct CommandList *c) +{ + /* + * Release our reference to the block. We don't need to do anything + * else to free it, because it is accessed by index. (There's no point + * in checking the result of the decrement, since we cannot guarantee + * that there isn't a concurrent abort which is also accessing it.) + */ + (void)atomic_dec(&c->refcount); +} + /* * For operations that cannot sleep, a command block is allocated at init, * and managed by cmd_alloc() and cmd_free() using a simple bitmap to track @@ -5411,7 +5495,7 @@ static struct CommandList *cmd_alloc(struct ctlr_info *h) { struct CommandList *c; int refcount, i; - unsigned long offset; + int offset = 0; /* * There is some *extremely* small but non-zero chance that that @@ -5423,12 +5507,20 @@ static struct CommandList *cmd_alloc(struct ctlr_info *h) * very unlucky thread might be starved anyway, never able to * beat the other threads. In reality, this happens so * infrequently as to be indistinguishable from never. + * + * Note that we start allocating commands before the SCSI host structure + * is initialized. Since the search starts at bit zero, this + * all works, since we have at least one command structure available; + * however, it means that the structures with the low indexes have to be + * reserved for driver-initiated requests, while requests from the block + * layer will use the higher indexes. */ - offset = h->last_allocation; /* benignly racy */ for (;;) { - i = find_next_zero_bit(h->cmd_pool_bits, h->nr_cmds, offset); - if (unlikely(i == h->nr_cmds)) { + i = find_next_zero_bit(h->cmd_pool_bits, + HPSA_NRESERVED_CMDS, + offset); + if (unlikely(i >= HPSA_NRESERVED_CMDS)) { offset = 0; continue; } @@ -5436,18 +5528,23 @@ static struct CommandList *cmd_alloc(struct ctlr_info *h) refcount = atomic_inc_return(&c->refcount); if (unlikely(refcount > 1)) { cmd_free(h, c); /* already in use */ - offset = (i + 1) % h->nr_cmds; + offset = (i + 1) % HPSA_NRESERVED_CMDS; continue; } set_bit(i & (BITS_PER_LONG - 1), h->cmd_pool_bits + (i / BITS_PER_LONG)); break; /* it's ours now. */ } - h->last_allocation = i; /* benignly racy */ hpsa_cmd_partial_init(h, i, c); return c; } +/* + * This is the complementary operation to cmd_alloc(). Note, however, in some + * corner cases it may also be used to free blocks allocated by + * cmd_tagged_alloc() in which case the ref-count decrement does the trick and + * the clear-bit is harmless. + */ static void cmd_free(struct ctlr_info *h, struct CommandList *c) { if (atomic_dec_and_test(&c->refcount)) { diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h index 3ec8934f0c70..2536b67e854f 100644 --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -141,7 +141,6 @@ struct ctlr_info { struct CfgTable __iomem *cfgtable; int interrupts_enabled; int max_commands; - int last_allocation; atomic_t commands_outstanding; # define PERF_MODE_INT 0 # define DOORBELL_INT 1