From: Ondrej Zary Date: Fri, 6 Feb 2015 22:11:55 +0000 (+0100) Subject: aha1542: rework locking X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=1b0224b0ec6003c06cc369188510642a5fb3b864;p=linux-beck.git aha1542: rework locking Remove aha1542_lock and use host_lock instead. Remove interrupt and queuecommand function wrappers. Remove locking from lowlevel _out and _in functions, they now can onle be called (at runtime) with host_lock being held. Remove ssleep(4) in aha1542_reset as we can't sleep while holding a spinlock. It's useless anyway as wait_mask will wait until the controller is idle and kernel waits for 10 seconds (HOST_RESET_SETTLE_TIME) after that. Signed-off-by: Ondrej Zary Reviewed-by: Christoph Hellwig Signed-off-by: James Bottomley --- diff --git a/drivers/scsi/aha1542.c b/drivers/scsi/aha1542.c index a19fcb02ff20..7b5d396deaa5 100644 --- a/drivers/scsi/aha1542.c +++ b/drivers/scsi/aha1542.c @@ -62,8 +62,6 @@ struct aha1542_hostdata { struct ccb ccb[AHA1542_MAILBOXES]; }; -static DEFINE_SPINLOCK(aha1542_lock); - static inline void aha1542_intr_reset(u16 base) { outb(IRST, CONTROL(base)); @@ -91,41 +89,25 @@ static inline bool wait_mask(u16 port, u8 mask, u8 allof, u8 noneof, int timeout return true; } -/* This is a bit complicated, but we need to make sure that an interrupt - routine does not send something out while we are in the middle of this. - Fortunately, it is only at boot time that multi-byte messages - are ever sent. */ static int aha1542_outb(unsigned int base, u8 val) { - unsigned long flags; - while (1) { if (!wait_mask(STATUS(base), CDF, 0, CDF, 0)) return 1; - spin_lock_irqsave(&aha1542_lock, flags); - if (inb(STATUS(base)) & CDF) { - spin_unlock_irqrestore(&aha1542_lock, flags); + if (inb(STATUS(base)) & CDF) continue; - } outb(val, DATA(base)); - spin_unlock_irqrestore(&aha1542_lock, flags); return 0; } } static int aha1542_out(unsigned int base, u8 *buf, int len) { - unsigned long flags; - - spin_lock_irqsave(&aha1542_lock, flags); while (len--) { - if (!wait_mask(STATUS(base), CDF, 0, CDF, 0)) { - spin_unlock_irqrestore(&aha1542_lock, flags); + if (!wait_mask(STATUS(base), CDF, 0, CDF, 0)) return 1; - } outb(*buf++, DATA(base)); } - spin_unlock_irqrestore(&aha1542_lock, flags); if (!wait_mask(INTRFLAGS(base), INTRMASK, HACC, 0, 0)) return 1; @@ -137,17 +119,11 @@ static int aha1542_out(unsigned int base, u8 *buf, int len) static int aha1542_in(unsigned int base, u8 *buf, int len, int timeout) { - unsigned long flags; - - spin_lock_irqsave(&aha1542_lock, flags); while (len--) { - if (!wait_mask(STATUS(base), DF, DF, 0, timeout)) { - spin_unlock_irqrestore(&aha1542_lock, flags); + if (!wait_mask(STATUS(base), DF, DF, 0, timeout)) return 1; - } *buf++ = inb(DATA(base)); } - spin_unlock_irqrestore(&aha1542_lock, flags); return 0; } @@ -260,9 +236,9 @@ static int aha1542_test_port(struct Scsi_Host *sh) return 1; } -/* A "high" level interrupt handler */ -static void aha1542_intr_handle(struct Scsi_Host *sh) +static irqreturn_t aha1542_interrupt(int irq, void *dev_id) { + struct Scsi_Host *sh = dev_id; struct aha1542_hostdata *aha1542 = shost_priv(sh); void (*my_done)(struct scsi_cmnd *) = NULL; int errstatus, mbi, mbo, mbistatus; @@ -292,7 +268,8 @@ static void aha1542_intr_handle(struct Scsi_Host *sh) #endif number_serviced = 0; - while (1 == 1) { + spin_lock_irqsave(sh->host_lock, flags); + while (1) { flag = inb(INTRFLAGS(sh->io_port)); /* Check for unusual interrupts. If any of these happen, we should @@ -309,7 +286,6 @@ static void aha1542_intr_handle(struct Scsi_Host *sh) } aha1542_intr_reset(sh->io_port); - spin_lock_irqsave(&aha1542_lock, flags); mbi = aha1542->aha1542_last_mbi_used + 1; if (mbi >= 2 * AHA1542_MAILBOXES) mbi = AHA1542_MAILBOXES; @@ -323,18 +299,17 @@ static void aha1542_intr_handle(struct Scsi_Host *sh) } while (mbi != aha1542->aha1542_last_mbi_used); if (mb[mbi].status == 0) { - spin_unlock_irqrestore(&aha1542_lock, flags); + spin_unlock_irqrestore(sh->host_lock, flags); /* Hmm, no mail. Must have read it the last time around */ if (!number_serviced) shost_printk(KERN_WARNING, sh, "interrupt received, but no mail.\n"); - return; + return IRQ_HANDLED; }; mbo = (scsi2int(mb[mbi].ccbptr) - (isa_virt_to_bus(&ccb[0]))) / sizeof(struct ccb); mbistatus = mb[mbi].status; mb[mbi].status = 0; aha1542->aha1542_last_mbi_used = mbi; - spin_unlock_irqrestore(&aha1542_lock, flags); #ifdef DEBUG if (ccb[mbo].tarstat | ccb[mbo].hastat) @@ -352,10 +327,11 @@ static void aha1542_intr_handle(struct Scsi_Host *sh) tmp_cmd = aha1542->int_cmds[mbo]; if (!tmp_cmd || !tmp_cmd->scsi_done) { + spin_unlock_irqrestore(sh->host_lock, flags); shost_printk(KERN_WARNING, sh, "Unexpected interrupt\n"); shost_printk(KERN_WARNING, sh, "tarstat=%x, hastat=%x idlun=%x ccb#=%d\n", ccb[mbo].tarstat, ccb[mbo].hastat, ccb[mbo].idlun, mbo); - return; + return IRQ_HANDLED; } my_done = tmp_cmd->scsi_done; kfree(tmp_cmd->host_scribble); @@ -394,21 +370,8 @@ static void aha1542_intr_handle(struct Scsi_Host *sh) }; } -/* A quick wrapper for do_aha1542_intr_handle to grab the spin lock */ -static irqreturn_t do_aha1542_intr_handle(int dummy, void *dev_id) +static int aha1542_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *cmd) { - unsigned long flags; - struct Scsi_Host *sh = dev_id; - - spin_lock_irqsave(sh->host_lock, flags); - aha1542_intr_handle(sh); - spin_unlock_irqrestore(sh->host_lock, flags); - return IRQ_HANDLED; -} - -static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct scsi_cmnd *)) -{ - struct Scsi_Host *sh = cmd->device->host; struct aha1542_hostdata *aha1542 = shost_priv(sh); u8 direction; u8 target = cmd->device->id; @@ -422,7 +385,7 @@ static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct if (*cmd->cmnd == REQUEST_SENSE) { /* Don't do the command - we have the sense data already */ cmd->result = 0; - done(cmd); + cmd->scsi_done(cmd); return 0; } #ifdef DEBUG @@ -440,7 +403,7 @@ static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct /* Use the outgoing mailboxes in a round-robin fashion, because this is how the host adapter will scan for them */ - spin_lock_irqsave(&aha1542_lock, flags); + spin_lock_irqsave(sh->host_lock, flags); mbo = aha1542->aha1542_last_mbo_used + 1; if (mbo >= AHA1542_MAILBOXES) mbo = 0; @@ -460,10 +423,9 @@ static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct screwing with this cdb. */ aha1542->aha1542_last_mbo_used = mbo; - spin_unlock_irqrestore(&aha1542_lock, flags); #ifdef DEBUG - shost_printk(KERN_DEBUG, sh, "Sending command (%d %p)...", mbo, done); + shost_printk(KERN_DEBUG, sh, "Sending command (%d %p)...", mbo, cmd->scsi_done); #endif any2scsi(mb[mbo].ccbptr, isa_virt_to_bus(&ccb[mbo])); /* This gets trashed for some reason */ @@ -492,6 +454,7 @@ static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct if (cptr == NULL) { /* free the claimed mailbox slot */ aha1542->int_cmds[mbo] = NULL; + spin_unlock_irqrestore(sh->host_lock, flags); return SCSI_MLQUEUE_HOST_BUSY; } scsi_for_each_sg(cmd, sg, sg_count, i) { @@ -518,23 +481,15 @@ static int aha1542_queuecommand_lck(struct scsi_cmnd *cmd, void (*done) (struct #ifdef DEBUG print_hex_dump_bytes("sending: ", DUMP_PREFIX_NONE, &ccb[mbo], sizeof(ccb[mbo]) - 10); + printk("aha1542_queuecommand: now waiting for interrupt "); #endif - - if (done) { -#ifdef DEBUG - printk("aha1542_queuecommand: now waiting for interrupt "); -#endif - cmd->scsi_done = done; - mb[mbo].status = 1; - aha1542_outb(cmd->device->host->io_port, CMD_START_SCSI); - } else - printk("aha1542_queuecommand: done can't be NULL\n"); + mb[mbo].status = 1; + aha1542_outb(cmd->device->host->io_port, CMD_START_SCSI); + spin_unlock_irqrestore(sh->host_lock, flags); return 0; } -static DEF_SCSI_QCMD(aha1542_queuecommand) - /* Initialize mailboxes */ static void setup_mailboxes(struct Scsi_Host *sh) { @@ -786,8 +741,7 @@ static struct Scsi_Host *aha1542_hw_init(struct scsi_host_template *tpnt, struct setup_mailboxes(sh); - if (request_irq(sh->irq, do_aha1542_intr_handle, 0, - "aha1542", sh)) { + if (request_irq(sh->irq, aha1542_interrupt, 0, "aha1542", sh)) { shost_printk(KERN_ERR, sh, "Unable to allocate IRQ.\n"); goto unregister; } @@ -841,7 +795,8 @@ static int aha1542_release(struct Scsi_Host *sh) */ static int aha1542_dev_reset(struct scsi_cmnd *cmd) { - struct aha1542_hostdata *aha1542 = shost_priv(cmd->device->host); + struct Scsi_Host *sh = cmd->device->host; + struct aha1542_hostdata *aha1542 = shost_priv(sh); unsigned long flags; struct mailbox *mb = aha1542->mb; u8 target = cmd->device->id; @@ -849,7 +804,7 @@ static int aha1542_dev_reset(struct scsi_cmnd *cmd) int mbo; struct ccb *ccb = aha1542->ccb; - spin_lock_irqsave(&aha1542_lock, flags); + spin_lock_irqsave(sh->host_lock, flags); mbo = aha1542->aha1542_last_mbo_used + 1; if (mbo >= AHA1542_MAILBOXES) mbo = 0; @@ -870,7 +825,6 @@ static int aha1542_dev_reset(struct scsi_cmnd *cmd) screwing with this cdb. */ aha1542->aha1542_last_mbo_used = mbo; - spin_unlock_irqrestore(&aha1542_lock, flags); any2scsi(mb[mbo].ccbptr, isa_virt_to_bus(&ccb[mbo])); /* This gets trashed for some reason */ @@ -887,7 +841,8 @@ static int aha1542_dev_reset(struct scsi_cmnd *cmd) * Now tell the 1542 to flush all pending commands for this * target */ - aha1542_outb(cmd->device->host->io_port, CMD_START_SCSI); + aha1542_outb(sh->io_port, CMD_START_SCSI); + spin_unlock_irqrestore(sh->host_lock, flags); scmd_printk(KERN_WARNING, cmd, "Trying device reset for target\n"); @@ -897,9 +852,12 @@ static int aha1542_dev_reset(struct scsi_cmnd *cmd) static int aha1542_reset(struct scsi_cmnd *cmd, u8 reset_cmd) { - struct aha1542_hostdata *aha1542 = shost_priv(cmd->device->host); + struct Scsi_Host *sh = cmd->device->host; + struct aha1542_hostdata *aha1542 = shost_priv(sh); + unsigned long flags; int i; + spin_lock_irqsave(sh->host_lock, flags); /* * This does a scsi reset for all devices on the bus. * In principle, we could also reset the 1542 - should @@ -908,27 +866,19 @@ static int aha1542_reset(struct scsi_cmnd *cmd, u8 reset_cmd) */ outb(reset_cmd, CONTROL(cmd->device->host->io_port)); - /* - * Wait for the thing to settle down a bit. Unfortunately - * this is going to basically lock up the machine while we - * wait for this to complete. To be 100% correct, we need to - * check for timeout, and if we are doing something like this - * we are pretty desperate anyways. - */ - ssleep(4); - spin_lock_irq(cmd->device->host->host_lock); - if (!wait_mask(STATUS(cmd->device->host->io_port), STATMASK, INIT | IDLE, STST | DIAGF | INVDCMD | DF | CDF, 0)) { - spin_unlock_irq(cmd->device->host->host_lock); + spin_unlock_irqrestore(sh->host_lock, flags); return FAILED; } + /* * We need to do this too before the 1542 can interact with * us again after host reset. */ if (reset_cmd & HRST) setup_mailboxes(cmd->device->host); + /* * Now try to pick up the pieces. For all pending commands, * free any internal data structures, and basically clear things @@ -958,7 +908,7 @@ static int aha1542_reset(struct scsi_cmnd *cmd, u8 reset_cmd) } } - spin_unlock_irq(cmd->device->host->host_lock); + spin_unlock_irqrestore(sh->host_lock, flags); return SUCCESS; }