[SCSI] sym2: Manage sym_lcb properly

Allocate the lcb in slave_alloc and free it in slave_destroy.  This allows
us to remove all the code that checks to see if it's already been allocated.

From: Christoph Hellwig <hch@lst.de>
Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

3 files changed, 38 insertions, 121 deletions

diff --git a/drivers/scsi/sym53c8xx_2/sym_glue.c b/drivers/scsi/sym53c8xx_2/sym_glue.c
index 7fc0b97173e1..a2bfdf8417a2 100644
--- a/drivers/scsi/sym53c8xx_2/sym_glue.c
+++ b/drivers/scsi/sym53c8xx_2/sym_glue.c
@@ -563,10 +563,7 @@ int sym_setup_data_and_start(struct sym_hcb *np, struct scsi_cmnd *cmd, struct s
         /*
          *      activate this job.
          */
-        if (lp)
-                sym_start_next_ccbs(np, lp, 2);
-        else
-                sym_put_start_queue(np, cp);
+        sym_start_next_ccbs(np, lp, 2);
         return 0;
 
 out_abort:
@@ -981,15 +978,13 @@ static int device_queue_depth(struct sym_hcb *np, int target, int lun)
 
 static int sym53c8xx_slave_alloc(struct scsi_device *sdev)
 {
-        struct sym_hcb *np;
-        struct sym_tcb *tp;
+        struct sym_hcb *np = sym_get_hcb(sdev->host);
+        struct sym_tcb *tp = &np->target[sdev->id];
+        struct sym_lcb *lp;
 
         if (sdev->id >= SYM_CONF_MAX_TARGET || sdev->lun >= SYM_CONF_MAX_LUN)
                 return -ENXIO;
 
-        np = sym_get_hcb(sdev->host);
-        tp = &np->target[sdev->id];
-
         /*
          * Fail the device init if the device is flagged NOSCAN at BOOT in
          * the NVRAM.  This may speed up boot and maintain coherency with
@@ -1005,6 +1000,10 @@ static int sym53c8xx_slave_alloc(struct scsi_device *sdev)
                 return -ENXIO;
         }
 
+        lp = sym_alloc_lcb(np, sdev->id, sdev->lun);
+        if (!lp)
+                return -ENOMEM;
+
         tp->starget = sdev->sdev_target;
         return 0;
 }
@@ -1012,22 +1011,14 @@ static int sym53c8xx_slave_alloc(struct scsi_device *sdev)
 /*
  * Linux entry point for device queue sizing.
  */
-static int sym53c8xx_slave_configure(struct scsi_device *device)
+static int sym53c8xx_slave_configure(struct scsi_device *sdev)
 {
-        struct sym_hcb *np = sym_get_hcb(device->host);
-        struct sym_tcb *tp = &np->target[device->id];
-        struct sym_lcb *lp;
+        struct sym_hcb *np = sym_get_hcb(sdev->host);
+        struct sym_tcb *tp = &np->target[sdev->id];
+        struct sym_lcb *lp = sym_lp(tp, sdev->lun);
         int reqtags, depth_to_use;
 
         /*
-         *  Allocate the LCB if not yet.
-         *  If it fail, we may well be in the sh*t. :)
-         */
-        lp = sym_alloc_lcb(np, device->id, device->lun);
-        if (!lp)
-                return -ENOMEM;
-
-        /*
          *  Get user flags.
          */
         lp->curr_flags = lp->user_flags;
@@ -1038,10 +1029,10 @@ static int sym53c8xx_slave_configure(struct scsi_device *device)
          *  Use at least 2.
          *  Donnot use more than our maximum.
          */
-        reqtags = device_queue_depth(np, device->id, device->lun);
+        reqtags = device_queue_depth(np, sdev->id, sdev->lun);
         if (reqtags > tp->usrtags)
                 reqtags = tp->usrtags;
-        if (!device->tagged_supported)
+        if (!sdev->tagged_supported)
                 reqtags = 0;
 #if 1 /* Avoid to locally queue commands for no good reasons */
         if (reqtags > SYM_CONF_MAX_TAG)
@@ -1050,19 +1041,30 @@ static int sym53c8xx_slave_configure(struct scsi_device *device)
 #else
         depth_to_use = (reqtags ? SYM_CONF_MAX_TAG : 2);
 #endif
-        scsi_adjust_queue_depth(device,
-                                (device->tagged_supported ?
+        scsi_adjust_queue_depth(sdev,
+                                (sdev->tagged_supported ?
                                  MSG_SIMPLE_TAG : 0),
                                 depth_to_use);
         lp->s.scdev_depth = depth_to_use;
-        sym_tune_dev_queuing(tp, device->lun, reqtags);
+        sym_tune_dev_queuing(tp, sdev->lun, reqtags);
 
-        if (!spi_initial_dv(device->sdev_target))
-                spi_dv_device(device);
+        if (!spi_initial_dv(sdev->sdev_target))
+                spi_dv_device(sdev);
 
         return 0;
 }
 
+static void sym53c8xx_slave_destroy(struct scsi_device *sdev)
+{
+        struct sym_hcb *np = sym_get_hcb(sdev->host);
+        struct sym_lcb *lp = sym_lp(&np->target[sdev->id], sdev->lun);
+
+        if (lp->itlq_tbl)
+                sym_mfree_dma(lp->itlq_tbl, SYM_CONF_MAX_TASK * 4, "ITLQ_TBL");
+        kfree(lp->cb_tags);
+        sym_mfree_dma(lp, sizeof(*lp), "LCB");
+}
+
 /*
  *  Linux entry point for info() function
  */
@@ -1926,6 +1928,7 @@ static struct scsi_host_template sym2_template = {
         .queuecommand           = sym53c8xx_queue_command,
         .slave_alloc            = sym53c8xx_slave_alloc,
         .slave_configure        = sym53c8xx_slave_configure,
+        .slave_destroy          = sym53c8xx_slave_destroy,
         .eh_abort_handler       = sym53c8xx_eh_abort_handler,
         .eh_device_reset_handler = sym53c8xx_eh_device_reset_handler,
         .eh_bus_reset_handler   = sym53c8xx_eh_bus_reset_handler,
diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.c b/drivers/scsi/sym53c8xx_2/sym_hipd.c
index 113e3b357163..bec644850d3b 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.c
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.c
@@ -1523,7 +1523,7 @@ static int sym_prepare_nego(struct sym_hcb *np, struct sym_ccb *cp, u_char *msgp
 /*
  *  Insert a job into the start queue.
  */
-void sym_put_start_queue(struct sym_hcb *np, struct sym_ccb *cp)
+static void sym_put_start_queue(struct sym_hcb *np, struct sym_ccb *cp)
 {
         u_short qidx;
 
@@ -4664,30 +4664,7 @@ struct sym_ccb *sym_get_ccb (struct sym_hcb *np, struct scsi_cmnd *cmd, u_char t
                 goto out;
         cp = sym_que_entry(qp, struct sym_ccb, link_ccbq);
 
-#ifndef SYM_OPT_HANDLE_DEVICE_QUEUEING
-        /*
-         *  If the LCB is not yet available and the LUN
-         *  has been probed ok, try to allocate the LCB.
-         */
-        if (!lp && sym_is_bit(tp->lun_map, ln)) {
-                lp = sym_alloc_lcb(np, tn, ln);
-                if (!lp)
-                        goto out_free;
-        }
-#endif
-
-        /*
-         *  If the LCB is not available here, then the 
-         *  logical unit is not yet discovered. For those 
-         *  ones only accept 1 SCSI IO per logical unit, 
-         *  since we cannot allow disconnections.
-         */
-        if (!lp) {
-                if (!sym_is_bit(tp->busy0_map, ln))
-                        sym_set_bit(tp->busy0_map, ln);
-                else
-                        goto out_free;
-        } else {
+        {
                 /*
                  *  If we have been asked for a tagged command.
                  */
@@ -4840,12 +4817,6 @@ void sym_free_ccb (struct sym_hcb *np, struct sym_ccb *cp)
                         lp->head.resel_sa =
                                 cpu_to_scr(SCRIPTB_BA(np, resel_bad_lun));
         }
-        /*
-         *  Otherwise, we only accept 1 IO per LUN.
-         *  Clear the bit that keeps track of this IO.
-         */
-        else
-                sym_clr_bit(tp->busy0_map, cp->lun);
 
         /*
          *  We donnot queue more than 1 ccb per target 
@@ -4997,20 +4968,7 @@ static void sym_init_tcb (struct sym_hcb *np, u_char tn)
 struct sym_lcb *sym_alloc_lcb (struct sym_hcb *np, u_char tn, u_char ln)
 {
         struct sym_tcb *tp = &np->target[tn];
-        struct sym_lcb *lp = sym_lp(tp, ln);
-
-        /*
-         *  Already done, just return.
-         */
-        if (lp)
-                return lp;
-
-        /*
-         *  Donnot allow LUN control block 
-         *  allocation for not probed LUNs.
-         */
-        if (!sym_is_bit(tp->lun_map, ln))
-                return NULL;
+        struct sym_lcb *lp = NULL;
 
         /*
          *  Initialize the target control block if not yet.
@@ -5082,13 +5040,7 @@ struct sym_lcb *sym_alloc_lcb (struct sym_hcb *np, u_char tn, u_char ln)
         lp->started_max   = SYM_CONF_MAX_TASK;
         lp->started_limit = SYM_CONF_MAX_TASK;
 #endif
-        /*
-         *  If we are busy, count the IO.
-         */
-        if (sym_is_bit(tp->busy0_map, ln)) {
-                lp->busy_itl = 1;
-                sym_clr_bit(tp->busy0_map, ln);
-        }
+
 fail:
         return lp;
 }
@@ -5103,12 +5055,6 @@ static void sym_alloc_lcb_tags (struct sym_hcb *np, u_char tn, u_char ln)
         int i;
 
         /*
-         *  If LCB not available, try to allocate it.
-         */
-        if (!lp && !(lp = sym_alloc_lcb(np, tn, ln)))
-                goto fail;
-
-        /*
          *  Allocate the task table and and the tag allocation 
          *  circular buffer. We want both or none.
          */
@@ -5481,8 +5427,7 @@ finish:
         /*
          *  Donnot start more than 1 command after an error.
          */
-        if (lp)
-                sym_start_next_ccbs(np, lp, 1);
+        sym_start_next_ccbs(np, lp, 1);
 #endif
 }
 
@@ -5521,12 +5466,6 @@ void sym_complete_ok (struct sym_hcb *np, struct sym_ccb *cp)
         lp = sym_lp(tp, cp->lun);
 
         /*
-         *  Assume device discovered on first success.
-         */
-        if (!lp)
-                sym_set_bit(tp->lun_map, cp->lun);
-
-        /*
          *  If all data have been transferred, given than no
          *  extended error did occur, there is no residual.
          */
@@ -5578,7 +5517,7 @@ if (resid)
         /*
          *  Requeue a couple of awaiting scsi commands.
          */
-        if (lp && !sym_que_empty(&lp->waiting_ccbq))
+        if (!sym_que_empty(&lp->waiting_ccbq))
                 sym_start_next_ccbs(np, lp, 2);
 #endif
         /*
@@ -5821,8 +5760,7 @@ void sym_hcb_free(struct sym_hcb *np)
         SYM_QUEHEAD *qp;
         struct sym_ccb *cp;
         struct sym_tcb *tp;
-        struct sym_lcb *lp;
-        int target, lun;
+        int target;
 
         if (np->scriptz0)
                 sym_mfree_dma(np->scriptz0, np->scriptz_sz, "SCRIPTZ0");
@@ -5848,16 +5786,6 @@ void sym_hcb_free(struct sym_hcb *np)
 
         for (target = 0; target < SYM_CONF_MAX_TARGET ; target++) {
                 tp = &np->target[target];
-                for (lun = 0 ; lun < SYM_CONF_MAX_LUN ; lun++) {
-                        lp = sym_lp(tp, lun);
-                        if (!lp)
-                                continue;
-                        if (lp->itlq_tbl)
-                                sym_mfree_dma(lp->itlq_tbl, SYM_CONF_MAX_TASK*4,
-                                       "ITLQ_TBL");
-                        kfree(lp->cb_tags);
-                        sym_mfree_dma(lp, sizeof(*lp), "LCB");
-                }
 #if SYM_CONF_MAX_LUN > 1
                 kfree(tp->lunmp);
 #endif 
diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.h b/drivers/scsi/sym53c8xx_2/sym_hipd.h
index 3a264a408216..756008812aa1 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.h
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.h
@@ -416,19 +416,6 @@ struct sym_tcb {
         struct sym_lcb **lunmp;         /* Other LCBs [1..MAX_LUN]      */
 #endif
 
-        /*
-         *  Bitmap that tells about LUNs that succeeded at least 
-         *  1 IO and therefore assumed to be a real device.
-         *  Avoid useless allocation of the LCB structure.
-         */
-        u32     lun_map[(SYM_CONF_MAX_LUN+31)/32];
-
-        /*
-         *  Bitmap that tells about LUNs that haven't yet an LCB 
-         *  allocated (not discovered or LCB allocation failed).
-         */
-        u32     busy0_map[(SYM_CONF_MAX_LUN+31)/32];
-
 #ifdef  SYM_HAVE_STCB
         /*
          *  O/S specific data structure.
@@ -1077,7 +1064,6 @@ char *sym_driver_name(void);
 void sym_print_xerr(struct scsi_cmnd *cmd, int x_status);
 int sym_reset_scsi_bus(struct sym_hcb *np, int enab_int);
 struct sym_chip *sym_lookup_chip_table(u_short device_id, u_char revision);
-void sym_put_start_queue(struct sym_hcb *np, struct sym_ccb *cp);
 #ifdef SYM_OPT_HANDLE_DEVICE_QUEUEING
 void sym_start_next_ccbs(struct sym_hcb *np, struct sym_lcb *lp, int maxn);
 #endif