Merge branch 'pending' of master.kernel.org:/pub/scm/linux/kernel/git/vxy/lksctp-dev

[linux-2.6] / drivers / scsi / scsi_lib.c

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 4560713ecb14a17baee5b8a5df3896ee40faf273..135c1d0547015e3ce54edcf634f24d3f7247cefb 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/bio.h>
+#include <linux/bitops.h>
 #include <linux/blkdev.h>
 #include <linux/completion.h>
 #include <linux/kernel.h>
@@ -34,13 +35,6 @@
 #define SG_MEMPOOL_NR          ARRAY_SIZE(scsi_sg_pools)
 #define SG_MEMPOOL_SIZE                2
 
-/*
- * The maximum number of SG segments that we will put inside a scatterlist
- * (unless chaining is used). Should ideally fit inside a single page, to
- * avoid a higher order allocation.
- */
-#define SCSI_MAX_SG_SEGMENTS   128
-
 struct scsi_host_sg_pool {
        size_t          size;
        char            *name;
@@ -48,19 +42,26 @@ struct scsi_host_sg_pool {
        mempool_t       *pool;
 };
 
-#define SP(x) { x, "sgpool-" #x }
+#define SP(x) { x, "sgpool-" __stringify(x) }
+#if (SCSI_MAX_SG_SEGMENTS < 32)
+#error SCSI_MAX_SG_SEGMENTS is too small (must be 32 or greater)
+#endif
 static struct scsi_host_sg_pool scsi_sg_pools[] = {
        SP(8),
        SP(16),
-#if (SCSI_MAX_SG_SEGMENTS > 16)
-       SP(32),
 #if (SCSI_MAX_SG_SEGMENTS > 32)
-       SP(64),
+       SP(32),
 #if (SCSI_MAX_SG_SEGMENTS > 64)
+       SP(64),
+#if (SCSI_MAX_SG_SEGMENTS > 128)
        SP(128),
+#if (SCSI_MAX_SG_SEGMENTS > 256)
+#error SCSI_MAX_SG_SEGMENTS is too large (256 MAX)
 #endif
 #endif
 #endif
+#endif
+       SP(SCSI_MAX_SG_SEGMENTS)
 };
 #undef SP
 
@@ -300,7 +301,6 @@ static int scsi_req_map_sg(struct request *rq, struct scatterlist *sgl,
                page = sg_page(sg);
                off = sg->offset;
                len = sg->length;
-               data_len += len;
 
                while (len > 0 && data_len > 0) {
                        /*
@@ -692,42 +692,16 @@ static struct scsi_cmnd *scsi_end_request(struct scsi_cmnd *cmd, int error,
        return NULL;
 }
 
-/*
- * Like SCSI_MAX_SG_SEGMENTS, but for archs that have sg chaining. This limit
- * is totally arbitrary, a setting of 2048 will get you at least 8mb ios.
- */
-#define SCSI_MAX_SG_CHAIN_SEGMENTS     2048
-
 static inline unsigned int scsi_sgtable_index(unsigned short nents)
 {
        unsigned int index;
 
-       switch (nents) {
-       case 1 ... 8:
+       BUG_ON(nents > SCSI_MAX_SG_SEGMENTS);
+
+       if (nents <= 8)
                index = 0;
-               break;
-       case 9 ... 16:
-               index = 1;
-               break;
-#if (SCSI_MAX_SG_SEGMENTS > 16)
-       case 17 ... 32:
-               index = 2;
-               break;
-#if (SCSI_MAX_SG_SEGMENTS > 32)
-       case 33 ... 64:
-               index = 3;
-               break;
-#if (SCSI_MAX_SG_SEGMENTS > 64)
-       case 65 ... 128:
-               index = 4;
-               break;
-#endif
-#endif
-#endif
-       default:
-               printk(KERN_ERR "scsi: bad segment count=%d\n", nents);
-               BUG();
-       }
+       else
+               index = get_count_order(nents) - 3;
 
        return index;
 }
@@ -1594,6 +1568,7 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
                                         request_fn_proc *request_fn)
 {
        struct request_queue *q;
+       struct device *dev = shost->shost_gendev.parent;
 
        q = blk_init_queue(request_fn, NULL);
        if (!q)
@@ -1603,24 +1578,14 @@ struct request_queue *__scsi_alloc_queue(struct Scsi_Host *shost,
         * this limit is imposed by hardware restrictions
         */
        blk_queue_max_hw_segments(q, shost->sg_tablesize);
-
-       /*
-        * In the future, sg chaining support will be mandatory and this
-        * ifdef can then go away. Right now we don't have all archs
-        * converted, so better keep it safe.
-        */
-#ifdef ARCH_HAS_SG_CHAIN
-       if (shost->use_sg_chaining)
-               blk_queue_max_phys_segments(q, SCSI_MAX_SG_CHAIN_SEGMENTS);
-       else
-               blk_queue_max_phys_segments(q, SCSI_MAX_SG_SEGMENTS);
-#else
-       blk_queue_max_phys_segments(q, SCSI_MAX_SG_SEGMENTS);
-#endif
+       blk_queue_max_phys_segments(q, SCSI_MAX_SG_CHAIN_SEGMENTS);
 
        blk_queue_max_sectors(q, shost->max_sectors);
        blk_queue_bounce_limit(q, scsi_calculate_bounce_limit(shost));
        blk_queue_segment_boundary(q, shost->dma_boundary);
+       dma_set_seg_boundary(dev, shost->dma_boundary);
+
+       blk_queue_max_segment_size(q, dma_get_max_seg_size(dev));
 
        if (!shost->use_clustering)
                clear_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
@@ -1720,7 +1685,7 @@ int __init scsi_init_queue(void)
                                        0, 0, NULL);
        if (!scsi_bidi_sdb_cache) {
                printk(KERN_ERR "SCSI: can't init scsi bidi sdb cache\n");
-               return -ENOMEM;
+               goto cleanup_io_context;
        }
 
        for (i = 0; i < SG_MEMPOOL_NR; i++) {
@@ -1732,6 +1697,7 @@ int __init scsi_init_queue(void)
                if (!sgp->slab) {
                        printk(KERN_ERR "SCSI: can't init sg slab %s\n",
                                        sgp->name);
+                       goto cleanup_bidi_sdb;
                }
 
                sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE,
@@ -1739,10 +1705,25 @@ int __init scsi_init_queue(void)
                if (!sgp->pool) {
                        printk(KERN_ERR "SCSI: can't init sg mempool %s\n",
                                        sgp->name);
+                       goto cleanup_bidi_sdb;
                }
        }
 
        return 0;
+
+cleanup_bidi_sdb:
+       for (i = 0; i < SG_MEMPOOL_NR; i++) {
+               struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;
+               if (sgp->pool)
+                       mempool_destroy(sgp->pool);
+               if (sgp->slab)
+                       kmem_cache_destroy(sgp->slab);
+       }
+       kmem_cache_destroy(scsi_bidi_sdb_cache);
+cleanup_io_context:
+       kmem_cache_destroy(scsi_io_context_cache);
+
+       return -ENOMEM;
 }
 
 void scsi_exit_queue(void)
@@ -1750,6 +1731,7 @@ void scsi_exit_queue(void)
        int i;
 
        kmem_cache_destroy(scsi_io_context_cache);
+       kmem_cache_destroy(scsi_bidi_sdb_cache);
 
        for (i = 0; i < SG_MEMPOOL_NR; i++) {
                struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;