diff options
| -rw-r--r-- | Documentation/cciss.txt | 29 | ||||
| -rw-r--r-- | drivers/block/cciss.c | 188 | ||||
| -rw-r--r-- | drivers/block/cciss.h | 11 | ||||
| -rw-r--r-- | drivers/block/cciss_scsi.c | 82 |
4 files changed, 283 insertions, 27 deletions
diff --git a/Documentation/cciss.txt b/Documentation/cciss.txt index 68a711fb82c..15378422fc4 100644 --- a/Documentation/cciss.txt +++ b/Documentation/cciss.txt @@ -133,3 +133,32 @@ hardware and it is important to prevent the kernel from attempting to directly access these devices too, as if the array controller were merely a SCSI controller in the same way that we are allowing it to access SCSI tape drives. +SCSI error handling for tape drives and medium changers +------------------------------------------------------- + +The linux SCSI mid layer provides an error handling protocol which +kicks into gear whenever a SCSI command fails to complete within a +certain amount of time (which can vary depending on the command). +The cciss driver participates in this protocol to some extent. The +normal protocol is a four step process. First the device is told +to abort the command. If that doesn't work, the device is reset. +If that doesn't work, the SCSI bus is reset. If that doesn't work +the host bus adapter is reset. Because the cciss driver is a block +driver as well as a SCSI driver and only the tape drives and medium +changers are presented to the SCSI mid layer, and unlike more +straightforward SCSI drivers, disk i/o continues through the block +side during the SCSI error recovery process, the cciss driver only +implements the first two of these actions, aborting the command, and +resetting the device. Additionally, most tape drives will not oblige +in aborting commands, and sometimes it appears they will not even +obey a reset coommand, though in most circumstances they will. In +the case that the command cannot be aborted and the device cannot be +reset, the device will be set offline. + +In the event the error handling code is triggered and a tape drive is +successfully reset or the tardy command is successfully aborted, the +tape drive may still not allow i/o to continue until some command +is issued which positions the tape to a known position. Typically you +must rewind the tape (by issuing "mt -f /dev/st0 rewind" for example) +before i/o can proceed again to a tape drive which was reset. + diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c index 486b6e1c7df..482786068ff 100644 --- a/drivers/block/cciss.c +++ b/drivers/block/cciss.c @@ -148,6 +148,7 @@ static struct board_type products[] = { static ctlr_info_t *hba[MAX_CTLR]; static void do_cciss_request(request_queue_t *q); +static irqreturn_t do_cciss_intr(int irq, void *dev_id, struct pt_regs *regs); static int cciss_open(struct inode *inode, struct file *filep); static int cciss_release(struct inode *inode, struct file *filep); static int cciss_ioctl(struct inode *inode, struct file *filep, @@ -1586,6 +1587,24 @@ static int fill_cmd(CommandList_struct *c, __u8 cmd, int ctlr, void *buff, } } else if (cmd_type == TYPE_MSG) { switch (cmd) { + case 0: /* ABORT message */ + c->Request.CDBLen = 12; + c->Request.Type.Attribute = ATTR_SIMPLE; + c->Request.Type.Direction = XFER_WRITE; + c->Request.Timeout = 0; + c->Request.CDB[0] = cmd; /* abort */ + c->Request.CDB[1] = 0; /* abort a command */ + /* buff contains the tag of the command to abort */ + memcpy(&c->Request.CDB[4], buff, 8); + break; + case 1: /* RESET message */ + c->Request.CDBLen = 12; + c->Request.Type.Attribute = ATTR_SIMPLE; + c->Request.Type.Direction = XFER_WRITE; + c->Request.Timeout = 0; + memset(&c->Request.CDB[0], 0, sizeof(c->Request.CDB)); + c->Request.CDB[0] = cmd; /* reset */ + c->Request.CDB[1] = 0x04; /* reset a LUN */ case 3: /* No-Op message */ c->Request.CDBLen = 1; c->Request.Type.Attribute = ATTR_SIMPLE; @@ -1872,6 +1891,52 @@ static unsigned long pollcomplete(int ctlr) /* Invalid address to tell caller we ran out of time */ return 1; } + +static int add_sendcmd_reject(__u8 cmd, int ctlr, unsigned long complete) +{ + /* We get in here if sendcmd() is polling for completions + and gets some command back that it wasn't expecting -- + something other than that which it just sent down. + Ordinarily, that shouldn't happen, but it can happen when + the scsi tape stuff gets into error handling mode, and + starts using sendcmd() to try to abort commands and + reset tape drives. In that case, sendcmd may pick up + completions of commands that were sent to logical drives + through the block i/o system, or cciss ioctls completing, etc. + In that case, we need to save those completions for later + processing by the interrupt handler. + */ + +#ifdef CONFIG_CISS_SCSI_TAPE + struct sendcmd_reject_list *srl = &hba[ctlr]->scsi_rejects; + + /* If it's not the scsi tape stuff doing error handling, (abort */ + /* or reset) then we don't expect anything weird. */ + if (cmd != CCISS_RESET_MSG && cmd != CCISS_ABORT_MSG) { +#endif + printk( KERN_WARNING "cciss cciss%d: SendCmd " + "Invalid command list address returned! (%lx)\n", + ctlr, complete); + /* not much we can do. */ +#ifdef CONFIG_CISS_SCSI_TAPE + return 1; + } + + /* We've sent down an abort or reset, but something else + has completed */ + if (srl->ncompletions >= (NR_CMDS + 2)) { + /* Uh oh. No room to save it for later... */ + printk(KERN_WARNING "cciss%d: Sendcmd: Invalid command addr, " + "reject list overflow, command lost!\n", ctlr); + return 1; + } + /* Save it for later */ + srl->complete[srl->ncompletions] = complete; + srl->ncompletions++; +#endif + return 0; +} + /* * Send a command to the controller, and wait for it to complete. * Only used at init time. @@ -1894,7 +1959,7 @@ static int sendcmd( unsigned long complete; ctlr_info_t *info_p= hba[ctlr]; u64bit buff_dma_handle; - int status; + int status, done = 0; if ((c = cmd_alloc(info_p, 1)) == NULL) { printk(KERN_WARNING "cciss: unable to get memory"); @@ -1916,7 +1981,9 @@ resend_cmd1: info_p->access.set_intr_mask(info_p, CCISS_INTR_OFF); /* Make sure there is room in the command FIFO */ - /* Actually it should be completely empty at this time. */ + /* Actually it should be completely empty at this time */ + /* unless we are in here doing error handling for the scsi */ + /* tape side of the driver. */ for (i = 200000; i > 0; i--) { /* if fifo isn't full go */ @@ -1933,13 +2000,25 @@ resend_cmd1: * Send the cmd */ info_p->access.submit_command(info_p, c); - complete = pollcomplete(ctlr); + done = 0; + do { + complete = pollcomplete(ctlr); #ifdef CCISS_DEBUG - printk(KERN_DEBUG "cciss: command completed\n"); + printk(KERN_DEBUG "cciss: command completed\n"); #endif /* CCISS_DEBUG */ - if (complete != 1) { + if (complete == 1) { + printk( KERN_WARNING + "cciss cciss%d: SendCmd Timeout out, " + "No command list address returned!\n", + ctlr); + status = IO_ERROR; + done = 1; + break; + } + + /* This will need to change for direct lookup completions */ if ( (complete & CISS_ERROR_BIT) && (complete & ~CISS_ERROR_BIT) == c->busaddr) { @@ -1979,6 +2058,10 @@ resend_cmd1: status = IO_ERROR; goto cleanup1; } + } else if (c->err_info->CommandStatus == CMD_UNABORTABLE) { + printk(KERN_WARNING "cciss%d: command could not be aborted.\n", ctlr); + status = IO_ERROR; + goto cleanup1; } printk(KERN_WARNING "ciss ciss%d: sendcmd" " Error %x \n", ctlr, @@ -1993,20 +2076,15 @@ resend_cmd1: goto cleanup1; } } + /* This will need changing for direct lookup completions */ if (complete != c->busaddr) { - printk( KERN_WARNING "cciss cciss%d: SendCmd " - "Invalid command list address returned! (%lx)\n", - ctlr, complete); - status = IO_ERROR; - goto cleanup1; - } - } else { - printk( KERN_WARNING - "cciss cciss%d: SendCmd Timeout out, " - "No command list address returned!\n", - ctlr); - status = IO_ERROR; - } + if (add_sendcmd_reject(cmd, ctlr, complete) != 0) { + BUG(); /* we are pretty much hosed if we get here. */ + } + continue; + } else + done = 1; + } while (!done); cleanup1: /* unlock the data buffer from DMA */ @@ -2014,6 +2092,11 @@ cleanup1: buff_dma_handle.val32.upper = c->SG[0].Addr.upper; pci_unmap_single(info_p->pdev, (dma_addr_t) buff_dma_handle.val, c->SG[0].Len, PCI_DMA_BIDIRECTIONAL); +#ifdef CONFIG_CISS_SCSI_TAPE + /* if we saved some commands for later, process them now. */ + if (info_p->scsi_rejects.ncompletions > 0) + do_cciss_intr(0, info_p, NULL); +#endif cmd_free(info_p, c, 1); return (status); } @@ -2338,6 +2421,48 @@ startio: start_io(h); } +static inline unsigned long get_next_completion(ctlr_info_t *h) +{ +#ifdef CONFIG_CISS_SCSI_TAPE + /* Any rejects from sendcmd() lying around? Process them first */ + if (h->scsi_rejects.ncompletions == 0) + return h->access.command_completed(h); + else { + struct sendcmd_reject_list *srl; + int n; + srl = &h->scsi_rejects; + n = --srl->ncompletions; + /* printk("cciss%d: processing saved reject\n", h->ctlr); */ + printk("p"); + return srl->complete[n]; + } +#else + return h->access.command_completed(h); +#endif +} + +static inline int interrupt_pending(ctlr_info_t *h) +{ +#ifdef CONFIG_CISS_SCSI_TAPE + return ( h->access.intr_pending(h) + || (h->scsi_rejects.ncompletions > 0)); +#else + return h->access.intr_pending(h); +#endif +} + +static inline long interrupt_not_for_us(ctlr_info_t *h) +{ +#ifdef CONFIG_CISS_SCSI_TAPE + return (((h->access.intr_pending(h) == 0) || + (h->interrupts_enabled == 0)) + && (h->scsi_rejects.ncompletions == 0)); +#else + return (((h->access.intr_pending(h) == 0) || + (h->interrupts_enabled == 0))); +#endif +} + static irqreturn_t do_cciss_intr(int irq, void *dev_id, struct pt_regs *regs) { ctlr_info_t *h = dev_id; @@ -2347,19 +2472,15 @@ static irqreturn_t do_cciss_intr(int irq, void *dev_id, struct pt_regs *regs) int j; int start_queue = h->next_to_run; - /* Is this interrupt for us? */ - if (( h->access.intr_pending(h) == 0) || (h->interrupts_enabled == 0)) + if (interrupt_not_for_us(h)) return IRQ_NONE; - /* * If there are completed commands in the completion queue, * we had better do something about it. */ spin_lock_irqsave(CCISS_LOCK(h->ctlr), flags); - while( h->access.intr_pending(h)) - { - while((a = h->access.command_completed(h)) != FIFO_EMPTY) - { + while (interrupt_pending(h)) { + while((a = get_next_completion(h)) != FIFO_EMPTY) { a1 = a; if ((a & 0x04)) { a2 = (a >> 3); @@ -2966,7 +3087,15 @@ static int __devinit cciss_init_one(struct pci_dev *pdev, printk( KERN_ERR "cciss: out of memory"); goto clean4; } - +#ifdef CONFIG_CISS_SCSI_TAPE + hba[i]->scsi_rejects.complete = + kmalloc(sizeof(hba[i]->scsi_rejects.complete[0]) * + (NR_CMDS + 5), GFP_KERNEL); + if (hba[i]->scsi_rejects.complete == NULL) { + printk( KERN_ERR "cciss: out of memory"); + goto clean4; + } +#endif spin_lock_init(&hba[i]->lock); /* Initialize the pdev driver private data. @@ -3034,6 +3163,10 @@ static int __devinit cciss_init_one(struct pci_dev *pdev, return(1); clean4: +#ifdef CONFIG_CISS_SCSI_TAPE + if(hba[i]->scsi_rejects.complete) + kfree(hba[i]->scsi_rejects.complete); +#endif if(hba[i]->cmd_pool_bits) kfree(hba[i]->cmd_pool_bits); if(hba[i]->cmd_pool) @@ -3107,6 +3240,9 @@ static void __devexit cciss_remove_one (struct pci_dev *pdev) pci_free_consistent(hba[i]->pdev, NR_CMDS * sizeof( ErrorInfo_struct), hba[i]->errinfo_pool, hba[i]->errinfo_pool_dhandle); kfree(hba[i]->cmd_pool_bits); +#ifdef CONFIG_CISS_SCSI_TAPE + kfree(hba[i]->scsi_rejects.complete); +#endif release_io_mem(hba[i]); free_hba(i); } diff --git a/drivers/block/cciss.h b/drivers/block/cciss.h index ef277baee9f..3b0858c8389 100644 --- a/drivers/block/cciss.h +++ b/drivers/block/cciss.h @@ -44,6 +44,14 @@ typedef struct _drive_info_struct */ } drive_info_struct; +#ifdef CONFIG_CISS_SCSI_TAPE + +struct sendcmd_reject_list { + int ncompletions; + unsigned long *complete; /* array of NR_CMDS tags */ +}; + +#endif struct ctlr_info { int ctlr; @@ -100,6 +108,9 @@ struct ctlr_info struct gendisk *gendisk[NWD]; #ifdef CONFIG_CISS_SCSI_TAPE void *scsi_ctlr; /* ptr to structure containing scsi related stuff */ + /* list of block side commands the scsi error handling sucked up */ + /* and saved for later processing */ + struct sendcmd_reject_list scsi_rejects; #endif unsigned char alive; }; diff --git a/drivers/block/cciss_scsi.c b/drivers/block/cciss_scsi.c index ec27976a57d..3226aa11c6e 100644 --- a/drivers/block/cciss_scsi.c +++ b/drivers/block/cciss_scsi.c @@ -42,6 +42,9 @@ #include "cciss_scsi.h" +#define CCISS_ABORT_MSG 0x00 +#define CCISS_RESET_MSG 0x01 + /* some prototypes... */ static int sendcmd( __u8 cmd, @@ -67,6 +70,8 @@ static int cciss_scsi_proc_info( static int cciss_scsi_queue_command (struct scsi_cmnd *cmd, void (* done)(struct scsi_cmnd *)); +static int cciss_eh_device_reset_handler(struct scsi_cmnd *); +static int cciss_eh_abort_handler(struct scsi_cmnd *); static struct cciss_scsi_hba_t ccissscsi[MAX_CTLR] = { { .name = "cciss0", .ndevices = 0 }, @@ -90,6 +95,9 @@ static struct scsi_host_template cciss_driver_template = { .sg_tablesize = MAXSGENTRIES, .cmd_per_lun = 1, .use_clustering = DISABLE_CLUSTERING, + /* Can't have eh_bus_reset_handler or eh_host_reset_handler for cciss */ + .eh_device_reset_handler= cciss_eh_device_reset_handler, + .eh_abort_handler = cciss_eh_abort_handler, }; #pragma pack(1) @@ -247,7 +255,7 @@ scsi_cmd_stack_free(int ctlr) #define DEVICETYPE(n) (n<0 || n>MAX_SCSI_DEVICE_CODE) ? \ "Unknown" : scsi_device_types[n] -#if 0 +#if 1 static int xmargin=8; static int amargin=60; @@ -1448,6 +1456,78 @@ cciss_proc_tape_report(int ctlr, unsigned char *buffer, off_t *pos, off_t *len) *pos += size; *len += size; } +/* Need at least one of these error handlers to keep ../scsi/hosts.c from + * complaining. Doing a host- or bus-reset can't do anything good here. + * Despite what it might say in scsi_error.c, there may well be commands + * on the controller, as the cciss driver registers twice, once as a block + * device for the logical drives, and once as a scsi device, for any tape + * drives. So we know there are no commands out on the tape drives, but we + * don't know there are no commands on the controller, and it is likely + * that there probably are, as the cciss block device is most commonly used + * as a boot device (embedded controller on HP/Compaq systems.) +*/ + +static int cciss_eh_device_reset_handler(struct scsi_cmnd *scsicmd) +{ + int rc; + CommandList_struct *cmd_in_trouble; + ctlr_info_t **c; + int ctlr; + + /* find the controller to which the command to be aborted was sent */ + c = (ctlr_info_t **) &scsicmd->device->host->hostdata[0]; + if (c == NULL) /* paranoia */ + return FAILED; + ctlr = (*c)->ctlr; + printk(KERN_WARNING "cciss%d: resetting tape drive or medium changer.\n", ctlr); + + /* find the command that's giving us trouble */ + cmd_in_trouble = (CommandList_struct *) scsicmd->host_scribble; + if (cmd_in_trouble == NULL) { /* paranoia */ + return FAILED; + } + /* send a reset to the SCSI LUN which the command was sent to */ + rc = sendcmd(CCISS_RESET_MSG, ctlr, NULL, 0, 2, 0, 0, + (unsigned char *) &cmd_in_trouble->Header.LUN.LunAddrBytes[0], + TYPE_MSG); + /* sendcmd turned off interrputs on the board, turn 'em back on. */ + (*c)->access.set_intr_mask(*c, CCISS_INTR_ON); + if (rc == 0) + return SUCCESS; + printk(KERN_WARNING "cciss%d: resetting device failed.\n", ctlr); + return FAILED; +} + +static int cciss_eh_abort_handler(struct scsi_cmnd *scsicmd) +{ + int rc; + CommandList_struct *cmd_to_abort; + ctlr_info_t **c; + int ctlr; + + /* find the controller to which the command to be aborted was sent */ + c = (ctlr_info_t **) &scsicmd->device->host->hostdata[0]; + if (c == NULL) /* paranoia */ + return FAILED; + ctlr = (*c)->ctlr; + printk(KERN_WARNING "cciss%d: aborting tardy SCSI cmd\n", ctlr); + + /* find the command to be aborted */ + cmd_to_abort = (CommandList_struct *) scsicmd->host_scribble; + if (cmd_to_abort == NULL) /* paranoia */ + return FAILED; + rc = sendcmd(CCISS_ABORT_MSG, ctlr, &cmd_to_abort->Header.Tag, + 0, 2, 0, 0, + (unsigned char *) &cmd_to_abort->Header.LUN.LunAddrBytes[0], + TYPE_MSG); + /* sendcmd turned off interrputs on the board, turn 'em back on. */ + (*c)->access.set_intr_mask(*c, CCISS_INTR_ON); + if (rc == 0) + return SUCCESS; + return FAILED; + +} + #else /* no CONFIG_CISS_SCSI_TAPE */ /* If no tape support, then these become defined out of existence */ |