1 files changed, 126 insertions, 59 deletions

diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index a026567f5d18..fb3d1e9bc407 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -16,9 +16,10 @@
  *  -- verify the 13 conditions and do bulk resets
  *  -- kill last_pipe and simply do two-state clearing on both pipes
  *  -- verify protocol (bulk) from USB descriptors (maybe...)
- *  -- highmem and sg
+ *  -- highmem
  *  -- move top_sense and work_bcs into separate allocations (if they survive)
  *     for cache purists and esoteric architectures.
+ *  -- Allocate structure for LUN 0 before the first ub_sync_tur, avoid NULL. ?
  *  -- prune comments, they are too volumnous
  *  -- Exterminate P3 printks
  *  -- Resove XXX's
@@ -171,7 +172,7 @@ struct bulk_cs_wrap {
  */
 struct ub_dev;
 
-#define UB_MAX_REQ_SG   1
+#define UB_MAX_REQ_SG   4
 #define UB_MAX_SECTORS 64
 
 /*
@@ -240,13 +241,21 @@ struct ub_scsi_cmd {
          */
         char *data;                     /* Requested buffer */
         unsigned int len;               /* Requested length */
-        // struct scatterlist sgv[UB_MAX_REQ_SG];
 
         struct ub_lun *lun;
         void (*done)(struct ub_dev *, struct ub_scsi_cmd *);
         void *back;
 };
 
+struct ub_request {
+        struct request *rq;
+        unsigned char dir;
+        unsigned int current_block;
+        unsigned int current_sg;
+        unsigned int nsg;               /* sgv[nsg] */
+        struct scatterlist sgv[UB_MAX_REQ_SG];
+};
+
 /*
  */
 struct ub_capacity {
@@ -342,6 +351,8 @@ struct ub_lun {
         int readonly;
         int first_open;                 /* Kludge. See ub_bd_open. */
 
+        struct ub_request urq;
+
         /* Use Ingo's mempool if or when we have more than one command. */
         /*
          * Currently we never need more than one command for the whole device.
@@ -389,6 +400,7 @@ struct ub_dev {
         struct bulk_cs_wrap work_bcs;
         struct usb_ctrlrequest work_cr;
 
+        int sg_stat[UB_MAX_REQ_SG+1];
         struct ub_scsi_trace tr;
 };
 
@@ -398,10 +410,14 @@ static void ub_cleanup(struct ub_dev *sc);
 static int ub_bd_rq_fn_1(struct ub_lun *lun, struct request *rq);
 static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
     struct ub_scsi_cmd *cmd, struct request *rq);
-static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
-    struct request *rq);
+static void ub_scsi_build_block(struct ub_lun *lun,
+    struct ub_scsi_cmd *cmd, struct ub_request *urq);
+static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
+    struct ub_scsi_cmd *cmd, struct request *rq);
 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static void ub_end_rq(struct request *rq, int uptodate);
+static int ub_request_advance(struct ub_dev *sc, struct ub_lun *lun,
+    struct ub_request *urq, struct ub_scsi_cmd *cmd);
 static int ub_submit_scsi(struct ub_dev *sc, struct ub_scsi_cmd *cmd);
 static void ub_urb_complete(struct urb *urb, struct pt_regs *pt);
 static void ub_scsi_action(unsigned long _dev);
@@ -523,6 +539,13 @@ static ssize_t ub_diag_show(struct device *dev, struct device_attribute *attr, c
         cnt += sprintf(page + cnt,
             "qlen %d qmax %d\n",
             sc->cmd_queue.qlen, sc->cmd_queue.qmax);
+        cnt += sprintf(page + cnt,
+            "sg %d %d %d %d %d\n",
+            sc->sg_stat[0],
+            sc->sg_stat[1],
+            sc->sg_stat[2],
+            sc->sg_stat[3],
+            sc->sg_stat[4]);
 
         list_for_each (p, &sc->luns) {
                 lun = list_entry(p, struct ub_lun, link);
@@ -769,14 +792,15 @@ static int ub_bd_rq_fn_1(struct ub_lun *lun, struct request *rq)
                 return 0;
         }
 
+        if (lun->urq.rq != NULL)
+                return -1;
         if ((cmd = ub_get_cmd(lun)) == NULL)
                 return -1;
         memset(cmd, 0, sizeof(struct ub_scsi_cmd));
 
         blkdev_dequeue_request(rq);
-
         if (blk_pc_request(rq)) {
-                rc = ub_cmd_build_packet(sc, cmd, rq);
+                rc = ub_cmd_build_packet(sc, lun, cmd, rq);
         } else {
                 rc = ub_cmd_build_block(sc, lun, cmd, rq);
         }
@@ -788,10 +812,10 @@ static int ub_bd_rq_fn_1(struct ub_lun *lun, struct request *rq)
         cmd->state = UB_CMDST_INIT;
         cmd->lun = lun;
         cmd->done = ub_rw_cmd_done;
-        cmd->back = rq;
+        cmd->back = &lun->urq;
 
         cmd->tag = sc->tagcnt++;
-        if ((rc = ub_submit_scsi(sc, cmd)) != 0) {
+        if (ub_submit_scsi(sc, cmd) != 0) {
                 ub_put_cmd(lun, cmd);
                 ub_end_rq(rq, 0);
                 return 0;
@@ -803,12 +827,12 @@ static int ub_bd_rq_fn_1(struct ub_lun *lun, struct request *rq)
 static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
     struct ub_scsi_cmd *cmd, struct request *rq)
 {
+        struct ub_request *urq;
         int ub_dir;
-#if 0 /* We use rq->buffer for now */
-        struct scatterlist *sg;
         int n_elem;
-#endif
-        unsigned int block, nblks;
+
+        urq = &lun->urq;
+        memset(urq, 0, sizeof(struct ub_request));
 
         if (rq_data_dir(rq) == WRITE)
                 ub_dir = UB_DIR_WRITE;
@@ -818,44 +842,19 @@ static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
         /*
          * get scatterlist from block layer
          */
-#if 0 /* We use rq->buffer for now */
-        sg = &cmd->sgv[0];
-        n_elem = blk_rq_map_sg(q, rq, sg);
+        n_elem = blk_rq_map_sg(lun->disk->queue, rq, &urq->sgv[0]);
         if (n_elem <= 0) {
-                ub_put_cmd(lun, cmd);
-                ub_end_rq(rq, 0);
-                blk_start_queue(q);
-                return 0;               /* request with no s/g entries? */
+                printk(KERN_INFO "%s: failed request map (%d)\n",
+                    sc->name, n_elem); /* P3 */
+                return -1;              /* request with no s/g entries? */
         }
-
-        if (n_elem != 1) {              /* Paranoia */
+        if (n_elem > UB_MAX_REQ_SG) {   /* Paranoia */
                 printk(KERN_WARNING "%s: request with %d segments\n",
                     sc->name, n_elem);
-                ub_put_cmd(lun, cmd);
-                ub_end_rq(rq, 0);
-                blk_start_queue(q);
-                return 0;
-        }
-#endif
-
-        /*
-         * XXX Unfortunately, this check does not work. It is quite possible
-         * to get bogus non-null rq->buffer if you allow sg by mistake.
-         */
-        if (rq->buffer == NULL) {
-                /*
-                 * This must not happen if we set the queue right.
-                 * The block level must create bounce buffers for us.
-                 */
-                static int do_print = 1;
-                if (do_print) {
-                        printk(KERN_WARNING "%s: unmapped block request"
-                            " flags 0x%lx sectors %lu\n",
-                            sc->name, rq->flags, rq->nr_sectors);
-                        do_print = 0;
-                }
                 return -1;
         }
+        urq->nsg = n_elem;
+        sc->sg_stat[n_elem]++;
 
         /*
          * build the command
@@ -863,10 +862,29 @@ static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
          * The call to blk_queue_hardsect_size() guarantees that request
          * is aligned, but it is given in terms of 512 byte units, always.
          */
-        block = rq->sector >> lun->capacity.bshift;
-        nblks = rq->nr_sectors >> lun->capacity.bshift;
+        urq->current_block = rq->sector >> lun->capacity.bshift;
+        // nblks = rq->nr_sectors >> lun->capacity.bshift;
+
+        urq->rq = rq;
+        urq->current_sg = 0;
+        urq->dir = ub_dir;
+
+        ub_scsi_build_block(lun, cmd, urq);
+        return 0;
+}
+
+static void ub_scsi_build_block(struct ub_lun *lun,
+    struct ub_scsi_cmd *cmd, struct ub_request *urq)
+{
+        struct scatterlist *sg;
+        unsigned int block, nblks;
+
+        sg = &urq->sgv[urq->current_sg];
+
+        block = urq->current_block;
+        nblks = sg->length >> (lun->capacity.bshift + 9);
 
-        cmd->cdb[0] = (ub_dir == UB_DIR_READ)? READ_10: WRITE_10;
+        cmd->cdb[0] = (urq->dir == UB_DIR_READ)? READ_10: WRITE_10;
         /* 10-byte uses 4 bytes of LBA: 2147483648KB, 2097152MB, 2048GB */
         cmd->cdb[2] = block >> 24;
         cmd->cdb[3] = block >> 16;
@@ -876,16 +894,20 @@ static int ub_cmd_build_block(struct ub_dev *sc, struct ub_lun *lun,
         cmd->cdb[8] = nblks;
         cmd->cdb_len = 10;
 
-        cmd->dir = ub_dir;
-        cmd->data = rq->buffer;
-        cmd->len = rq->nr_sectors * 512;
-
-        return 0;
+        cmd->dir = urq->dir;
+        cmd->data = page_address(sg->page) + sg->offset;
+        cmd->len = sg->length;
 }
 
-static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
-    struct request *rq)
+static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_lun *lun,
+    struct ub_scsi_cmd *cmd, struct request *rq)
 {
+        struct ub_request *urq;
+
+        urq = &lun->urq;
+        memset(urq, 0, sizeof(struct ub_request));
+        urq->rq = rq;
+        sc->sg_stat[0]++;
 
         if (rq->data_len != 0 && rq->data == NULL) {
                 static int do_print = 1;
@@ -917,12 +939,13 @@ static int ub_cmd_build_packet(struct ub_dev *sc, struct ub_scsi_cmd *cmd,
 
 static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
 {
-        struct request *rq = cmd->back;
         struct ub_lun *lun = cmd->lun;
-        struct gendisk *disk = lun->disk;
-        request_queue_t *q = disk->queue;
+        struct ub_request *urq = cmd->back;
+        struct request *rq;
         int uptodate;
 
+        rq = urq->rq;
+
         if (blk_pc_request(rq)) {
                 /* UB_SENSE_SIZE is smaller than SCSI_SENSE_BUFFERSIZE */
                 memcpy(rq->sense, sc->top_sense, UB_SENSE_SIZE);
@@ -934,9 +957,19 @@ static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
         else
                 uptodate = 0;
 
+        if (cmd->error == 0 && urq->current_sg+1 < urq->nsg) {
+                if (ub_request_advance(sc, lun, urq, cmd) == 0) {
+                        /* Stay on target... */
+                        return;
+                }
+                uptodate = 0;
+        }
+
+        urq->rq = NULL;
+
         ub_put_cmd(lun, cmd);
         ub_end_rq(rq, uptodate);
-        blk_start_queue(q);
+        blk_start_queue(lun->disk->queue);
 }
 
 static void ub_end_rq(struct request *rq, int uptodate)
@@ -948,6 +981,40 @@ static void ub_end_rq(struct request *rq, int uptodate)
         end_that_request_last(rq);
 }
 
+static int ub_request_advance(struct ub_dev *sc, struct ub_lun *lun,
+    struct ub_request *urq, struct ub_scsi_cmd *cmd)
+{
+        struct scatterlist *sg;
+        unsigned int nblks;
+
+        /* XXX This is temporary, until we sort out S/G in packet requests. */
+        if (blk_pc_request(urq->rq)) {
+                printk(KERN_WARNING
+                    "2-segment packet request completed\n"); /* P3 */
+                return -1;
+        }
+
+        sg = &urq->sgv[urq->current_sg];
+        nblks = sg->length >> (lun->capacity.bshift + 9);
+        urq->current_block += nblks;
+        urq->current_sg++;
+        sg++;
+
+        memset(cmd, 0, sizeof(struct ub_scsi_cmd));
+        ub_scsi_build_block(lun, cmd, urq);
+        cmd->state = UB_CMDST_INIT;
+        cmd->lun = lun;
+        cmd->done = ub_rw_cmd_done;
+        cmd->back = &lun->urq;
+
+        cmd->tag = sc->tagcnt++;
+        if (ub_submit_scsi(sc, cmd) != 0) {
+                return -1;
+        }
+
+        return 0;
+}
+
 /*
  * Submit a regular SCSI operation (not an auto-sense).
  *