scsi_debug: append inject error flags onto scsi_cmnd object

The way the existing scsi_debug command parser associated various
inject error flags to a command was difficult to replicate in the
table driven parser. This patch adds infrastructure to append those
flags to the end of a scsi_cmnd object with the cmd_size host
template option.

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 68 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index a1bca60ae83d..d337eaa128d0 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -209,6 +209,14 @@ static const char *scsi_debug_version_date = "20141022";
 #warning "Expect DEF_CMD_PER_LUN <= SCSI_DEBUG_CANQUEUE"
 #endif
 
+struct sdebug_scmd_extra_t {
+        bool inj_recovered;
+        bool inj_transport;
+        bool inj_dif;
+        bool inj_dix;
+        bool inj_short;
+};
+
 static int scsi_debug_add_host = DEF_NUM_HOST;
 static int scsi_debug_ato = DEF_ATO;
 static int scsi_debug_delay = DEF_DELAY;
@@ -248,6 +256,7 @@ static unsigned int scsi_debug_write_same_length = DEF_WRITESAME_LENGTH;
 static bool scsi_debug_removable = DEF_REMOVABLE;
 static bool scsi_debug_clustering;
 static bool scsi_debug_host_lock = DEF_HOST_LOCK;
+static bool sdebug_any_injecting_opt;
 
 static atomic_t sdebug_cmnd_count;
 static atomic_t sdebug_completions;
@@ -3416,6 +3425,16 @@ static ssize_t opts_store(struct device_driver *ddp, const char *buf,
         return -EINVAL;
 opts_done:
         scsi_debug_opts = opts;
+        if (SCSI_DEBUG_OPT_RECOVERED_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_TRANSPORT_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_DIF_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_DIX_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & opts)
+                sdebug_any_injecting_opt = true;
         atomic_set(&sdebug_cmnd_count, 0);
         atomic_set(&sdebug_a_tsf, 0);
         return count;
@@ -4563,6 +4582,41 @@ sdebug_change_qtype(struct scsi_device *sdev, int qtype)
         return qtype;
 }
 
+static int
+check_inject(struct scsi_cmnd *scp)
+{
+        struct sdebug_scmd_extra_t *ep = scsi_cmd_priv(scp);
+
+        memset(ep, 0, sizeof(struct sdebug_scmd_extra_t));
+
+        if (atomic_inc_return(&sdebug_cmnd_count) >=
+            abs(scsi_debug_every_nth)) {
+                atomic_set(&sdebug_cmnd_count, 0);
+                if (scsi_debug_every_nth < -1)
+                        scsi_debug_every_nth = -1;
+                if (SCSI_DEBUG_OPT_TIMEOUT & scsi_debug_opts)
+                        return 1; /* ignore command causing timeout */
+                else if (SCSI_DEBUG_OPT_MAC_TIMEOUT & scsi_debug_opts &&
+                         scsi_medium_access_command(scp))
+                        return 1; /* time out reads and writes */
+                if (sdebug_any_injecting_opt) {
+                        int opts = scsi_debug_opts;
+
+                        if (SCSI_DEBUG_OPT_RECOVERED_ERR & opts)
+                                ep->inj_recovered = true;
+                        else if (SCSI_DEBUG_OPT_TRANSPORT_ERR & opts)
+                                ep->inj_transport = true;
+                        else if (SCSI_DEBUG_OPT_DIF_ERR & opts)
+                                ep->inj_dif = true;
+                        else if (SCSI_DEBUG_OPT_DIX_ERR & opts)
+                                ep->inj_dix = true;
+                        else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & opts)
+                                ep->inj_short = true;
+                }
+        }
+        return 0;
+}
+
 static struct scsi_host_template sdebug_driver_template = {
         .show_info =            scsi_debug_show_info,
         .write_info =           scsi_debug_write_info,
@@ -4589,11 +4643,13 @@ static struct scsi_host_template sdebug_driver_template = {
         .use_clustering =       DISABLE_CLUSTERING,
         .module =               THIS_MODULE,
         .track_queue_depth =    1,
+        .cmd_size =             sizeof(struct sdebug_scmd_extra_t),
 };
 
 static int sdebug_driver_probe(struct device * dev)
 {
         int error = 0;
+        int opts;
         struct sdebug_host_info *sdbg_host;
         struct Scsi_Host *hpnt;
         int host_prot;
@@ -4662,6 +4718,18 @@ static int sdebug_driver_probe(struct device * dev)
         else
                 scsi_host_set_guard(hpnt, SHOST_DIX_GUARD_CRC);
 
+        opts = scsi_debug_opts;
+        if (SCSI_DEBUG_OPT_RECOVERED_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_TRANSPORT_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_DIF_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_DIX_ERR & opts)
+                sdebug_any_injecting_opt = true;
+        else if (SCSI_DEBUG_OPT_SHORT_TRANSFER & opts)
+                sdebug_any_injecting_opt = true;
+
         error = scsi_add_host(hpnt, &sdbg_host->dev);
         if (error) {
                 printk(KERN_ERR "%s: scsi_add_host failed\n", __func__);