diff options
| -rw-r--r-- | drivers/scsi/scsi_debug.c | 197 |
1 files changed, 146 insertions, 51 deletions
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 2104973a35cd..24f3905f054f 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -33,6 +33,7 @@ #include <linux/blkdev.h> #include <linux/crc-t10dif.h> #include <linux/spinlock.h> +#include <linux/mutex.h> #include <linux/interrupt.h> #include <linux/atomic.h> #include <linux/hrtimer.h> @@ -730,7 +731,9 @@ static const struct opcode_info_t opcode_info_arr[SDEB_I_LAST_ELEM_P1 + 1] = { {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} }, }; -static int sdebug_num_hosts; +static atomic_t sdebug_num_hosts; +static DEFINE_MUTEX(add_host_mutex); + static int sdebug_add_host = DEF_NUM_HOST; /* in sysfs this is relative */ static int sdebug_ato = DEF_ATO; static int sdebug_cdb_len = DEF_CDB_LEN; @@ -777,6 +780,7 @@ static int sdebug_uuid_ctl = DEF_UUID_CTL; static bool sdebug_random = DEF_RANDOM; static bool sdebug_per_host_store = DEF_PER_HOST_STORE; static bool sdebug_removable = DEF_REMOVABLE; +static bool sdebug_deflect_incoming; static bool sdebug_clustering; static bool sdebug_host_lock = DEF_HOST_LOCK; static bool sdebug_strict = DEF_STRICT; @@ -5026,6 +5030,10 @@ static int scsi_debug_slave_configure(struct scsi_device *sdp) sdp->host->host_no, sdp->channel, sdp->id, sdp->lun); if (sdp->host->max_cmd_len != SDEBUG_MAX_CMD_LEN) sdp->host->max_cmd_len = SDEBUG_MAX_CMD_LEN; + if (smp_load_acquire(&sdebug_deflect_incoming)) { + pr_info("Exit early due to deflect_incoming\n"); + return 1; + } if (devip == NULL) { devip = find_build_dev_info(sdp); if (devip == NULL) @@ -5111,7 +5119,7 @@ static bool stop_queued_cmnd(struct scsi_cmnd *cmnd) } /* Deletes (stops) timers or work queues of all queued commands */ -static void stop_all_queued(void) +static void stop_all_queued(bool done_with_no_conn) { unsigned long iflags; int j, k; @@ -5120,13 +5128,15 @@ static void stop_all_queued(void) struct sdebug_queued_cmd *sqcp; struct sdebug_dev_info *devip; struct sdebug_defer *sd_dp; + struct scsi_cmnd *scp; for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) { spin_lock_irqsave(&sqp->qc_lock, iflags); for (k = 0; k < SDEBUG_CANQUEUE; ++k) { if (test_bit(k, sqp->in_use_bm)) { sqcp = &sqp->qc_arr[k]; - if (sqcp->a_cmnd == NULL) + scp = sqcp->a_cmnd; + if (!scp) continue; devip = (struct sdebug_dev_info *) sqcp->a_cmnd->device->hostdata; @@ -5141,6 +5151,10 @@ static void stop_all_queued(void) l_defer_t = SDEB_DEFER_NONE; spin_unlock_irqrestore(&sqp->qc_lock, iflags); stop_qc_helper(sd_dp, l_defer_t); + if (done_with_no_conn && l_defer_t != SDEB_DEFER_NONE) { + scp->result = DID_NO_CONNECT << 16; + scsi_done(scp); + } clear_bit(k, sqp->in_use_bm); spin_lock_irqsave(&sqp->qc_lock, iflags); } @@ -5283,7 +5297,7 @@ static int scsi_debug_host_reset(struct scsi_cmnd *SCpnt) } } spin_unlock(&sdebug_host_list_lock); - stop_all_queued(); + stop_all_queued(false); if (SDEBUG_OPT_RESET_NOISE & sdebug_opts) sdev_printk(KERN_INFO, SCpnt->device, "%s: %d device(s) found\n", __func__, k); @@ -5343,13 +5357,50 @@ static void sdebug_build_parts(unsigned char *ramp, unsigned long store_size) } } -static void block_unblock_all_queues(bool block) +static void sdeb_block_all_queues(void) +{ + int j; + struct sdebug_queue *sqp; + + for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) + atomic_set(&sqp->blocked, (int)true); +} + +static void sdeb_unblock_all_queues(void) { int j; struct sdebug_queue *sqp; for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) - atomic_set(&sqp->blocked, (int)block); + atomic_set(&sqp->blocked, (int)false); +} + +static void +sdeb_add_n_hosts(int num_hosts) +{ + if (num_hosts < 1) + return; + do { + bool found; + unsigned long idx; + struct sdeb_store_info *sip; + bool want_phs = (sdebug_fake_rw == 0) && sdebug_per_host_store; + + found = false; + if (want_phs) { + xa_for_each_marked(per_store_ap, idx, sip, SDEB_XA_NOT_IN_USE) { + sdeb_most_recent_idx = (int)idx; + found = true; + break; + } + if (found) /* re-use case */ + sdebug_add_host_helper((int)idx); + else + sdebug_do_add_host(true /* make new store */); + } else { + sdebug_do_add_host(false); + } + } while (--num_hosts); } /* Adjust (by rounding down) the sdebug_cmnd_count so abs(every_nth)-1 @@ -5362,10 +5413,10 @@ static void tweak_cmnd_count(void) modulo = abs(sdebug_every_nth); if (modulo < 2) return; - block_unblock_all_queues(true); + sdeb_block_all_queues(); count = atomic_read(&sdebug_cmnd_count); atomic_set(&sdebug_cmnd_count, (count / modulo) * modulo); - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); } static void clear_queue_stats(void) @@ -5383,6 +5434,15 @@ static bool inject_on_this_cmd(void) return (atomic_read(&sdebug_cmnd_count) % abs(sdebug_every_nth)) == 0; } +static int process_deflect_incoming(struct scsi_cmnd *scp) +{ + u8 opcode = scp->cmnd[0]; + + if (opcode == SYNCHRONIZE_CACHE || opcode == SYNCHRONIZE_CACHE_16) + return 0; + return DID_NO_CONNECT << 16; +} + #define INCLUSIVE_TIMING_MAX_NS 1000000 /* 1 millisecond */ /* Complete the processing of the thread that queued a SCSI command to this @@ -5392,8 +5452,7 @@ static bool inject_on_this_cmd(void) */ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip, int scsi_result, - int (*pfp)(struct scsi_cmnd *, - struct sdebug_dev_info *), + int (*pfp)(struct scsi_cmnd *, struct sdebug_dev_info *), int delta_jiff, int ndelay) { bool new_sd_dp; @@ -5414,13 +5473,27 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip, } sdp = cmnd->device; - if (delta_jiff == 0) + if (delta_jiff == 0) { + sqp = get_queue(cmnd); + if (atomic_read(&sqp->blocked)) { + if (smp_load_acquire(&sdebug_deflect_incoming)) + return process_deflect_incoming(cmnd); + else + return SCSI_MLQUEUE_HOST_BUSY; + } goto respond_in_thread; + } sqp = get_queue(cmnd); spin_lock_irqsave(&sqp->qc_lock, iflags); if (unlikely(atomic_read(&sqp->blocked))) { spin_unlock_irqrestore(&sqp->qc_lock, iflags); + if (smp_load_acquire(&sdebug_deflect_incoming)) { + scsi_result = process_deflect_incoming(cmnd); + goto respond_in_thread; + } + if (sdebug_verbose) + pr_info("blocked --> SCSI_MLQUEUE_HOST_BUSY\n"); return SCSI_MLQUEUE_HOST_BUSY; } num_in_q = atomic_read(&devip->num_in_q); @@ -5616,8 +5689,12 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip, respond_in_thread: /* call back to mid-layer using invocation thread */ cmnd->result = pfp != NULL ? pfp(cmnd, devip) : 0; cmnd->result &= ~SDEG_RES_IMMED_MASK; - if (cmnd->result == 0 && scsi_result != 0) + if (cmnd->result == 0 && scsi_result != 0) { cmnd->result = scsi_result; + if (sdebug_verbose) + pr_info("respond_in_thread: tag=0x%x, scp->result=0x%x\n", + blk_mq_unique_tag(scsi_cmd_to_rq(cmnd)), scsi_result); + } scsi_done(cmnd); return 0; } @@ -5900,7 +5977,7 @@ static ssize_t delay_store(struct device_driver *ddp, const char *buf, int j, k; struct sdebug_queue *sqp; - block_unblock_all_queues(true); + sdeb_block_all_queues(); for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) { k = find_first_bit(sqp->in_use_bm, @@ -5914,7 +5991,7 @@ static ssize_t delay_store(struct device_driver *ddp, const char *buf, sdebug_jdelay = jdelay; sdebug_ndelay = 0; } - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); } return res; } @@ -5940,7 +6017,7 @@ static ssize_t ndelay_store(struct device_driver *ddp, const char *buf, int j, k; struct sdebug_queue *sqp; - block_unblock_all_queues(true); + sdeb_block_all_queues(); for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) { k = find_first_bit(sqp->in_use_bm, @@ -5955,7 +6032,7 @@ static ssize_t ndelay_store(struct device_driver *ddp, const char *buf, sdebug_jdelay = ndelay ? JDELAY_OVERRIDDEN : DEF_JDELAY; } - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); } return res; } @@ -6269,7 +6346,7 @@ static ssize_t max_queue_store(struct device_driver *ddp, const char *buf, if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n > 0) && (n <= SDEBUG_CANQUEUE) && (sdebug_host_max_queue == 0)) { - block_unblock_all_queues(true); + sdeb_block_all_queues(); k = 0; for (j = 0, sqp = sdebug_q_arr; j < submit_queues; ++j, ++sqp) { @@ -6284,7 +6361,7 @@ static ssize_t max_queue_store(struct device_driver *ddp, const char *buf, atomic_set(&retired_max_queue, k + 1); else atomic_set(&retired_max_queue, 0); - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); return count; } return -EINVAL; @@ -6356,43 +6433,48 @@ static DRIVER_ATTR_RW(virtual_gb); static ssize_t add_host_show(struct device_driver *ddp, char *buf) { /* absolute number of hosts currently active is what is shown */ - return scnprintf(buf, PAGE_SIZE, "%d\n", sdebug_num_hosts); + return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&sdebug_num_hosts)); } +/* + * Accept positive and negative values. Hex values (only positive) may be prefixed by '0x'. + * To remove all hosts use a large negative number (e.g. -9999). The value 0 does nothing. + * Returns -EBUSY if another add_host sysfs invocation is active. + */ static ssize_t add_host_store(struct device_driver *ddp, const char *buf, size_t count) { - bool found; - unsigned long idx; - struct sdeb_store_info *sip; - bool want_phs = (sdebug_fake_rw == 0) && sdebug_per_host_store; int delta_hosts; - if (sscanf(buf, "%d", &delta_hosts) != 1) + if (count == 0 || kstrtoint(buf, 0, &delta_hosts)) return -EINVAL; + if (sdebug_verbose) + pr_info("prior num_hosts=%d, num_to_add=%d\n", + atomic_read(&sdebug_num_hosts), delta_hosts); + if (delta_hosts == 0) + return count; + if (mutex_trylock(&add_host_mutex) == 0) + return -EBUSY; if (delta_hosts > 0) { - do { - found = false; - if (want_phs) { - xa_for_each_marked(per_store_ap, idx, sip, - SDEB_XA_NOT_IN_USE) { - sdeb_most_recent_idx = (int)idx; - found = true; - break; - } - if (found) /* re-use case */ - sdebug_add_host_helper((int)idx); - else - sdebug_do_add_host(true); - } else { - sdebug_do_add_host(false); - } - } while (--delta_hosts); + sdeb_add_n_hosts(delta_hosts); } else if (delta_hosts < 0) { + smp_store_release(&sdebug_deflect_incoming, true); + sdeb_block_all_queues(); + if (delta_hosts >= atomic_read(&sdebug_num_hosts)) + stop_all_queued(true); do { + if (atomic_read(&sdebug_num_hosts) < 1) { + free_all_queued(); + break; + } sdebug_do_remove_host(false); } while (++delta_hosts); + sdeb_unblock_all_queues(); + smp_store_release(&sdebug_deflect_incoming, false); } + mutex_unlock(&add_host_mutex); + if (sdebug_verbose) + pr_info("post num_hosts=%d\n", atomic_read(&sdebug_num_hosts)); return count; } static DRIVER_ATTR_RW(add_host); @@ -6902,6 +6984,10 @@ static int __init scsi_debug_init(void) sdebug_add_host = 0; for (k = 0; k < hosts_to_add; k++) { + if (smp_load_acquire(&sdebug_deflect_incoming)) { + pr_info("exit early as sdebug_deflect_incoming is set\n"); + return 0; + } if (want_store && k == 0) { ret = sdebug_add_host_helper(idx); if (ret < 0) { @@ -6919,8 +7005,12 @@ static int __init scsi_debug_init(void) } } if (sdebug_verbose) - pr_info("built %d host(s)\n", sdebug_num_hosts); + pr_info("built %d host(s)\n", atomic_read(&sdebug_num_hosts)); + /* + * Even though all the hosts have been established, due to async device (LU) scanning + * by the scsi mid-level, there may still be devices (LUs) being set up. + */ return 0; bus_unreg: @@ -6936,12 +7026,17 @@ free_q_arr: static void __exit scsi_debug_exit(void) { - int k = sdebug_num_hosts; + int k; - stop_all_queued(); - for (; k; k--) + /* Possible race with LUs still being set up; stop them asap */ + sdeb_block_all_queues(); + smp_store_release(&sdebug_deflect_incoming, true); + stop_all_queued(false); + for (k = 0; atomic_read(&sdebug_num_hosts) > 0; k++) sdebug_do_remove_host(true); free_all_queued(); + if (sdebug_verbose) + pr_info("removed %d hosts\n", k); driver_unregister(&sdebug_driverfs_driver); bus_unregister(&pseudo_lld_bus); root_device_unregister(pseudo_primary); @@ -7111,13 +7206,13 @@ static int sdebug_add_host_helper(int per_host_idx) sdbg_host->dev.bus = &pseudo_lld_bus; sdbg_host->dev.parent = pseudo_primary; sdbg_host->dev.release = &sdebug_release_adapter; - dev_set_name(&sdbg_host->dev, "adapter%d", sdebug_num_hosts); + dev_set_name(&sdbg_host->dev, "adapter%d", atomic_read(&sdebug_num_hosts)); error = device_register(&sdbg_host->dev); if (error) goto clean; - ++sdebug_num_hosts; + atomic_inc(&sdebug_num_hosts); return 0; clean: @@ -7181,7 +7276,7 @@ static void sdebug_do_remove_host(bool the_end) return; device_unregister(&sdbg_host->dev); - --sdebug_num_hosts; + atomic_dec(&sdebug_num_hosts); } static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth) @@ -7189,10 +7284,10 @@ static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth) int num_in_q = 0; struct sdebug_dev_info *devip; - block_unblock_all_queues(true); + sdeb_block_all_queues(); devip = (struct sdebug_dev_info *)sdev->hostdata; if (NULL == devip) { - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); return -ENODEV; } num_in_q = atomic_read(&devip->num_in_q); @@ -7211,7 +7306,7 @@ static int sdebug_change_qdepth(struct scsi_device *sdev, int qdepth) sdev_printk(KERN_INFO, sdev, "%s: qdepth=%d, num_in_q=%d\n", __func__, qdepth, num_in_q); } - block_unblock_all_queues(false); + sdeb_unblock_all_queues(); return sdev->queue_depth; } |