forked from mirrors/linux
		
	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 <scott.teel@pmcs.com>
Reviewed-by: Kevin Barnett <kevin.barnett@pmcs.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Reviewed-by: Hannes Reinecke <hare@Suse.de>
Signed-off-by: Webb Scales <webbnh@hp.com>
Signed-off-by: Don Brace <don.brace@pmcs.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
			
			
This commit is contained in:
		
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						commit
						73153fe533
					
				
					 2 changed files with 129 additions and 33 deletions
				
			
		| 
						 | 
					@ -44,6 +44,7 @@
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#include <scsi/scsi_host.h>
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					#include <scsi/scsi_host.h>
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#include <scsi/scsi_tcq.h>
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					#include <scsi/scsi_tcq.h>
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#include <scsi/scsi_eh.h>
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					#include <scsi/scsi_eh.h>
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					#include <scsi/scsi_dbg.h>
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#include <linux/cciss_ioctl.h>
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					#include <linux/cciss_ioctl.h>
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#include <linux/string.h>
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					#include <linux/string.h>
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#include <linux/bitmap.h>
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					#include <linux/bitmap.h>
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					@ -212,6 +213,9 @@ static int hpsa_compat_ioctl(struct scsi_device *dev, int cmd,
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static void cmd_free(struct ctlr_info *h, struct CommandList *c);
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					static void cmd_free(struct ctlr_info *h, struct CommandList *c);
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static struct CommandList *cmd_alloc(struct ctlr_info *h);
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					static struct CommandList *cmd_alloc(struct ctlr_info *h);
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					static void cmd_tagged_free(struct ctlr_info *h, struct CommandList *c);
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					static struct CommandList *cmd_tagged_alloc(struct ctlr_info *h,
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										    struct scsi_cmnd *scmd);
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static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
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					static int fill_cmd(struct CommandList *c, u8 cmd, struct ctlr_info *h,
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	void *buff, size_t size, u16 page_code, unsigned char *scsi3addr,
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						void *buff, size_t size, u16 page_code, unsigned char *scsi3addr,
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	int cmd_type);
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						int cmd_type);
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						 | 
					@ -2010,11 +2014,17 @@ static void hpsa_cmd_resolve_events(struct ctlr_info *h,
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	}
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						}
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}
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					}
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					static void hpsa_cmd_resolve_and_free(struct ctlr_info *h,
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									      struct CommandList *c)
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					{
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						hpsa_cmd_resolve_events(h, c);
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						cmd_tagged_free(h, c);
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					}
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static void hpsa_cmd_free_and_done(struct ctlr_info *h,
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					static void hpsa_cmd_free_and_done(struct ctlr_info *h,
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		struct CommandList *c, struct scsi_cmnd *cmd)
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							struct CommandList *c, struct scsi_cmnd *cmd)
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{
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					{
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	hpsa_cmd_resolve_events(h, c);
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						hpsa_cmd_resolve_and_free(h, c);
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	cmd_free(h, c);
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					 | 
				
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	cmd->scsi_done(cmd);
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						cmd->scsi_done(cmd);
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}
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					}
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					@ -2035,8 +2045,7 @@ static void hpsa_cmd_abort_and_free(struct ctlr_info *h, struct CommandList *c,
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	hpsa_set_scsi_cmd_aborted(cmd);
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						hpsa_set_scsi_cmd_aborted(cmd);
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	dev_warn(&h->pdev->dev, "CDB %16phN was aborted with status 0x%x\n",
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						dev_warn(&h->pdev->dev, "CDB %16phN was aborted with status 0x%x\n",
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			 c->Request.CDB, c->err_info->ScsiStatus);
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								 c->Request.CDB, c->err_info->ScsiStatus);
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	hpsa_cmd_resolve_events(h, c);
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						hpsa_cmd_resolve_and_free(h, c);
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	cmd_free(h, c);		/* FIX-ME:  change to cmd_tagged_free(h, c) */
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}
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					}
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static void process_ioaccel2_completion(struct ctlr_info *h,
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					static void process_ioaccel2_completion(struct ctlr_info *h,
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					@ -4500,7 +4509,7 @@ static int hpsa_ciss_submit(struct ctlr_info *h,
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	}
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						}
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	if (hpsa_scatter_gather(h, c, cmd) < 0) { /* Fill SG list */
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						if (hpsa_scatter_gather(h, c, cmd) < 0) { /* Fill SG list */
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		cmd_free(h, c);
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							hpsa_cmd_resolve_and_free(h, c);
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		return SCSI_MLQUEUE_HOST_BUSY;
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							return SCSI_MLQUEUE_HOST_BUSY;
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	}
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						}
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	enqueue_cmd_and_start_io(h, c);
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						enqueue_cmd_and_start_io(h, c);
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					@ -4546,6 +4555,8 @@ static inline void hpsa_cmd_partial_init(struct ctlr_info *h, int index,
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{
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					{
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	dma_addr_t cmd_dma_handle = h->cmd_pool_dhandle + index * sizeof(*c);
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						dma_addr_t cmd_dma_handle = h->cmd_pool_dhandle + index * sizeof(*c);
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						BUG_ON(c->cmdindex != index);
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	memset(c->Request.CDB, 0, sizeof(c->Request.CDB));
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						memset(c->Request.CDB, 0, sizeof(c->Request.CDB));
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	memset(c->err_info, 0, sizeof(*c->err_info));
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						memset(c->err_info, 0, sizeof(*c->err_info));
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	c->busaddr = (u32) cmd_dma_handle;
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						c->busaddr = (u32) cmd_dma_handle;
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					@ -4640,12 +4651,16 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
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	/* Get the ptr to our adapter structure out of cmd->host. */
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						/* Get the ptr to our adapter structure out of cmd->host. */
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	h = sdev_to_hba(cmd->device);
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						h = sdev_to_hba(cmd->device);
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						BUG_ON(cmd->request->tag < 0);
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	dev = cmd->device->hostdata;
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						dev = cmd->device->hostdata;
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	if (!dev) {
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						if (!dev) {
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		cmd->result = DID_NO_CONNECT << 16;
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							cmd->result = DID_NO_CONNECT << 16;
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		cmd->scsi_done(cmd);
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							cmd->scsi_done(cmd);
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		return 0;
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							return 0;
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	}
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						}
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	memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr));
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						memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr));
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	if (unlikely(lockup_detected(h))) {
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						if (unlikely(lockup_detected(h))) {
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					@ -4653,14 +4668,7 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
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		cmd->scsi_done(cmd);
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							cmd->scsi_done(cmd);
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		return 0;
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							return 0;
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	}
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						}
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	c = cmd_alloc(h);
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						c = cmd_tagged_alloc(h, cmd);
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	if (unlikely(lockup_detected(h))) {
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		cmd->result = DID_NO_CONNECT << 16;
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		cmd_free(h, c);
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		cmd->scsi_done(cmd);
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		return 0;
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	}
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	/*
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						/*
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	 * Call alternate submit routine for I/O accelerated commands.
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						 * Call alternate submit routine for I/O accelerated commands.
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					@ -4673,7 +4681,7 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd)
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		if (rc == 0)
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							if (rc == 0)
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			return 0;
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								return 0;
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		if (rc == SCSI_MLQUEUE_HOST_BUSY) {
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							if (rc == SCSI_MLQUEUE_HOST_BUSY) {
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			cmd_free(h, c);
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								hpsa_cmd_resolve_and_free(h, c);
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			return SCSI_MLQUEUE_HOST_BUSY;
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								return SCSI_MLQUEUE_HOST_BUSY;
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		}
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							}
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	}
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						}
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					@ -4787,15 +4795,23 @@ static int hpsa_register_scsi(struct ctlr_info *h)
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	sh->hostdata[0] = (unsigned long) h;
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						sh->hostdata[0] = (unsigned long) h;
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	sh->irq = h->intr[h->intr_mode];
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						sh->irq = h->intr[h->intr_mode];
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	sh->unique_id = sh->irq;
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						sh->unique_id = sh->irq;
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	error = scsi_add_host(sh, &h->pdev->dev);
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						error = scsi_init_shared_tag_map(sh, sh->can_queue);
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	if (error)
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						if (error) {
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							dev_err(&h->pdev->dev,
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								"%s: scsi_init_shared_tag_map failed for controller %d\n",
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								__func__, h->ctlr);
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		goto fail_host_put;
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							goto fail_host_put;
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						}
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						error = scsi_add_host(sh, &h->pdev->dev);
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						if (error) {
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							dev_err(&h->pdev->dev, "%s: scsi_add_host failed for controller %d\n",
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								__func__, h->ctlr);
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							goto fail_host_put;
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						}
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	scsi_scan_host(sh);
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						scsi_scan_host(sh);
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	return 0;
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						return 0;
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 fail_host_put:
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					 fail_host_put:
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	dev_err(&h->pdev->dev, "%s: scsi_add_host"
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		" failed for controller %d\n", __func__, h->ctlr);
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	scsi_host_put(sh);
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						scsi_host_put(sh);
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	return error;
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						return error;
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 fail:
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					 fail:
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					@ -4804,6 +4820,23 @@ static int hpsa_register_scsi(struct ctlr_info *h)
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	return -ENOMEM;
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						return -ENOMEM;
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}
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					}
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					/*
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					 * The block layer has already gone to the trouble of picking out a unique,
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					 * small-integer tag for this request.  We use an offset from that value as
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					 * an index to select our command block.  (The offset allows us to reserve the
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					 * low-numbered entries for our own uses.)
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					 */
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					static int hpsa_get_cmd_index(struct scsi_cmnd *scmd)
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					{
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						int idx = scmd->request->tag;
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						if (idx < 0)
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							return idx;
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						/* Offset to leave space for internal cmds. */
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						return idx += HPSA_NRESERVED_CMDS;
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					}
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/*
 | 
					/*
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 * Send a TEST_UNIT_READY command to the specified LUN using the specified
 | 
					 * Send a TEST_UNIT_READY command to the specified LUN using the specified
 | 
				
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 * reply queue; returns zero if the unit is ready, and non-zero otherwise.
 | 
					 * reply queue; returns zero if the unit is ready, and non-zero otherwise.
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						 | 
					@ -4925,6 +4958,7 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd)
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	int rc;
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						int rc;
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	struct ctlr_info *h;
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						struct ctlr_info *h;
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	struct hpsa_scsi_dev_t *dev;
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						struct hpsa_scsi_dev_t *dev;
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 | 
						char msg[40];
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	/* find the controller to which the command to be aborted was sent */
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						/* find the controller to which the command to be aborted was sent */
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	h = sdev_to_hba(scsicmd->device);
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						h = sdev_to_hba(scsicmd->device);
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						 | 
					@ -4943,19 +4977,17 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd)
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	/* if controller locked up, we can guarantee command won't complete */
 | 
						/* if controller locked up, we can guarantee command won't complete */
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	if (lockup_detected(h)) {
 | 
						if (lockup_detected(h)) {
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		dev_warn(&h->pdev->dev,
 | 
							sprintf(msg, "cmd %d RESET FAILED, lockup detected",
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			"scsi %d:%d:%d:%d RESET FAILED, lockup detected\n",
 | 
									hpsa_get_cmd_index(scsicmd));
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			h->scsi_host->host_no, dev->bus, dev->target,
 | 
							hpsa_show_dev_msg(KERN_WARNING, h, dev, msg);
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			dev->lun);
 | 
					 | 
				
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		return FAILED;
 | 
							return FAILED;
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	}
 | 
						}
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	/* this reset request might be the result of a lockup; check */
 | 
						/* this reset request might be the result of a lockup; check */
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	if (detect_controller_lockup(h)) {
 | 
						if (detect_controller_lockup(h)) {
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		dev_warn(&h->pdev->dev,
 | 
							sprintf(msg, "cmd %d RESET FAILED, new lockup detected",
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			 "scsi %d:%d:%d:%d RESET FAILED, new lockup detected\n",
 | 
									hpsa_get_cmd_index(scsicmd));
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			 h->scsi_host->host_no, dev->bus, dev->target,
 | 
							hpsa_show_dev_msg(KERN_WARNING, h, dev, msg);
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			 dev->lun);
 | 
					 | 
				
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		return FAILED;
 | 
							return FAILED;
 | 
				
			||||||
	}
 | 
						}
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						 | 
					@ -5398,6 +5430,58 @@ static int hpsa_eh_abort_handler(struct scsi_cmnd *sc)
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	return !lockup_detected(h) ? SUCCESS : FAILED;
 | 
						return !lockup_detected(h) ? SUCCESS : FAILED;
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			||||||
}
 | 
					}
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 | 
					/*
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 | 
					 * For operations with an associated SCSI command, a command block is allocated
 | 
				
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 | 
					 * at init, and managed by cmd_tagged_alloc() and cmd_tagged_free() using the
 | 
				
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 | 
					 * block request tag as an index into a table of entries.  cmd_tagged_free() is
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 | 
					 * the complement, although cmd_free() may be called instead.
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 | 
					 */
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 | 
					static struct CommandList *cmd_tagged_alloc(struct ctlr_info *h,
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 | 
										    struct scsi_cmnd *scmd)
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 | 
					{
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 | 
						int idx = hpsa_get_cmd_index(scmd);
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 | 
						struct CommandList *c = h->cmd_pool + idx;
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 | 
						if (idx < HPSA_NRESERVED_CMDS || idx >= h->nr_cmds) {
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 | 
							dev_err(&h->pdev->dev, "Bad block tag: %d not in [%d..%d]\n",
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 | 
								idx, HPSA_NRESERVED_CMDS, h->nr_cmds - 1);
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 | 
							/* The index value comes from the block layer, so if it's out of
 | 
				
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 | 
							 * bounds, it's probably not our bug.
 | 
				
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 | 
							 */
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 | 
							BUG();
 | 
				
			||||||
 | 
						}
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 | 
					
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 | 
						atomic_inc(&c->refcount);
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 | 
						if (unlikely(!hpsa_is_cmd_idle(c))) {
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 | 
							/*
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 | 
							 * We expect that the SCSI layer will hand us a unique tag
 | 
				
			||||||
 | 
							 * value.  Thus, there should never be a collision here between
 | 
				
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 | 
							 * two requests...because if the selected command isn't idle
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			||||||
 | 
							 * then someone is going to be very disappointed.
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			||||||
 | 
							 */
 | 
				
			||||||
 | 
							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,
 | 
					 * 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
 | 
					 * 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;
 | 
						struct CommandList *c;
 | 
				
			||||||
	int refcount, i;
 | 
						int refcount, i;
 | 
				
			||||||
	unsigned long offset;
 | 
						int offset = 0;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
	/*
 | 
						/*
 | 
				
			||||||
	 * There is some *extremely* small but non-zero chance that that
 | 
						 * 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
 | 
						 * very unlucky thread might be starved anyway, never able to
 | 
				
			||||||
	 * beat the other threads.  In reality, this happens so
 | 
						 * beat the other threads.  In reality, this happens so
 | 
				
			||||||
	 * infrequently as to be indistinguishable from never.
 | 
						 * 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 (;;) {
 | 
						for (;;) {
 | 
				
			||||||
		i = find_next_zero_bit(h->cmd_pool_bits, h->nr_cmds, offset);
 | 
							i = find_next_zero_bit(h->cmd_pool_bits,
 | 
				
			||||||
		if (unlikely(i == h->nr_cmds)) {
 | 
										HPSA_NRESERVED_CMDS,
 | 
				
			||||||
 | 
										offset);
 | 
				
			||||||
 | 
							if (unlikely(i >= HPSA_NRESERVED_CMDS)) {
 | 
				
			||||||
			offset = 0;
 | 
								offset = 0;
 | 
				
			||||||
			continue;
 | 
								continue;
 | 
				
			||||||
		}
 | 
							}
 | 
				
			||||||
| 
						 | 
					@ -5436,18 +5528,23 @@ static struct CommandList *cmd_alloc(struct ctlr_info *h)
 | 
				
			||||||
		refcount = atomic_inc_return(&c->refcount);
 | 
							refcount = atomic_inc_return(&c->refcount);
 | 
				
			||||||
		if (unlikely(refcount > 1)) {
 | 
							if (unlikely(refcount > 1)) {
 | 
				
			||||||
			cmd_free(h, c); /* already in use */
 | 
								cmd_free(h, c); /* already in use */
 | 
				
			||||||
			offset = (i + 1) % h->nr_cmds;
 | 
								offset = (i + 1) % HPSA_NRESERVED_CMDS;
 | 
				
			||||||
			continue;
 | 
								continue;
 | 
				
			||||||
		}
 | 
							}
 | 
				
			||||||
		set_bit(i & (BITS_PER_LONG - 1),
 | 
							set_bit(i & (BITS_PER_LONG - 1),
 | 
				
			||||||
			h->cmd_pool_bits + (i / BITS_PER_LONG));
 | 
								h->cmd_pool_bits + (i / BITS_PER_LONG));
 | 
				
			||||||
		break; /* it's ours now. */
 | 
							break; /* it's ours now. */
 | 
				
			||||||
	}
 | 
						}
 | 
				
			||||||
	h->last_allocation = i; /* benignly racy */
 | 
					 | 
				
			||||||
	hpsa_cmd_partial_init(h, i, c);
 | 
						hpsa_cmd_partial_init(h, i, c);
 | 
				
			||||||
	return 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)
 | 
					static void cmd_free(struct ctlr_info *h, struct CommandList *c)
 | 
				
			||||||
{
 | 
					{
 | 
				
			||||||
	if (atomic_dec_and_test(&c->refcount)) {
 | 
						if (atomic_dec_and_test(&c->refcount)) {
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
| 
						 | 
					@ -141,7 +141,6 @@ struct ctlr_info {
 | 
				
			||||||
	struct CfgTable __iomem *cfgtable;
 | 
						struct CfgTable __iomem *cfgtable;
 | 
				
			||||||
	int	interrupts_enabled;
 | 
						int	interrupts_enabled;
 | 
				
			||||||
	int 	max_commands;
 | 
						int 	max_commands;
 | 
				
			||||||
	int last_allocation;
 | 
					 | 
				
			||||||
	atomic_t commands_outstanding;
 | 
						atomic_t commands_outstanding;
 | 
				
			||||||
#	define PERF_MODE_INT	0
 | 
					#	define PERF_MODE_INT	0
 | 
				
			||||||
#	define DOORBELL_INT	1
 | 
					#	define DOORBELL_INT	1
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
		Loading…
	
		Reference in a new issue