3 files changed, 119 insertions, 43 deletions

diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.c b/drivers/scsi/mpt2sas/mpt2sas_base.c
index 0e30827d44e7..c8f39f8c6fed 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.c
@@ -65,7 +65,6 @@
 static MPT_CALLBACK     mpt_callbacks[MPT_MAX_CALLBACKS];
 
 #define FAULT_POLLING_INTERVAL 1000 /* in milliseconds */
-#define MPT2SAS_MAX_REQUEST_QUEUE 600 /* maximum controller queue depth */
 
 static int max_queue_depth = -1;
 module_param(max_queue_depth, int, 0);
@@ -1497,6 +1496,7 @@ mpt2sas_base_free_smid(struct MPT2SAS_ADAPTER *ioc, u16 smid)
 {
         unsigned long flags;
         int i;
+        struct chain_tracker *chain_req, *next;
 
         spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
         if (smid >= ioc->hi_priority_smid) {
@@ -1519,6 +1519,14 @@ mpt2sas_base_free_smid(struct MPT2SAS_ADAPTER *ioc, u16 smid)
 
         /* scsiio queue */
         i = smid - 1;
+        if (!list_empty(&ioc->scsi_lookup[i].chain_list)) {
+                list_for_each_entry_safe(chain_req, next,
+                    &ioc->scsi_lookup[i].chain_list, tracker_list) {
+                        list_del_init(&chain_req->tracker_list);
+                        list_add_tail(&chain_req->tracker_list,
+                            &ioc->free_chain_list);
+                }
+        }
         ioc->scsi_lookup[i].cb_idx = 0xFF;
         ioc->scsi_lookup[i].scmd = NULL;
         list_add_tail(&ioc->scsi_lookup[i].tracker_list,
@@ -1968,6 +1976,8 @@ _base_static_config_pages(struct MPT2SAS_ADAPTER *ioc)
 static void
 _base_release_memory_pools(struct MPT2SAS_ADAPTER *ioc)
 {
+        int i;
+
         dexitprintk(ioc, printk(MPT2SAS_INFO_FMT "%s\n", ioc->name,
             __func__));
 
@@ -2032,6 +2042,20 @@ _base_release_memory_pools(struct MPT2SAS_ADAPTER *ioc)
         }
         kfree(ioc->hpr_lookup);
         kfree(ioc->internal_lookup);
+        if (ioc->chain_lookup) {
+                for (i = 0; i < ioc->chain_depth; i++) {
+                        if (ioc->chain_lookup[i].chain_buffer)
+                                pci_pool_free(ioc->chain_dma_pool,
+                                    ioc->chain_lookup[i].chain_buffer,
+                                    ioc->chain_lookup[i].chain_buffer_dma);
+                }
+                if (ioc->chain_dma_pool)
+                        pci_pool_destroy(ioc->chain_dma_pool);
+        }
+        if (ioc->chain_lookup) {
+                free_pages((ulong)ioc->chain_lookup, ioc->chain_pages);
+                ioc->chain_lookup = NULL;
+        }
 }
 
 
@@ -2053,6 +2077,7 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
         u32 sz, total_sz;
         u32 retry_sz;
         u16 max_request_credit;
+        int i;
 
         dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "%s\n", ioc->name,
             __func__));
@@ -2070,14 +2095,11 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
         }
 
         /* command line tunables  for max controller queue depth */
-        if (max_queue_depth != -1) {
+        if (max_queue_depth != -1)
                 max_request_credit = (max_queue_depth < facts->RequestCredit)
                     ? max_queue_depth : facts->RequestCredit;
-        } else {
-                max_request_credit = (facts->RequestCredit >
-                    MPT2SAS_MAX_REQUEST_QUEUE) ? MPT2SAS_MAX_REQUEST_QUEUE :
-                    facts->RequestCredit;
-        }
+        else
+                max_request_credit = facts->RequestCredit;
 
         ioc->hba_queue_depth = max_request_credit;
         ioc->hi_priority_depth = facts->HighPriorityCredit;
@@ -2183,7 +2205,7 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
          * "frame for smid=0
          */
         ioc->chain_depth = ioc->chains_needed_per_io * ioc->scsiio_depth;
-        sz = ((ioc->scsiio_depth + 1 + ioc->chain_depth) * ioc->request_sz);
+        sz = ((ioc->scsiio_depth + 1) * ioc->request_sz);
 
         /* hi-priority queue */
         sz += (ioc->hi_priority_depth * ioc->request_sz);
@@ -2224,19 +2246,11 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
         ioc->internal_dma = ioc->hi_priority_dma + (ioc->hi_priority_depth *
             ioc->request_sz);
 
-        ioc->chain = ioc->internal + (ioc->internal_depth *
-            ioc->request_sz);
-        ioc->chain_dma = ioc->internal_dma + (ioc->internal_depth *
-            ioc->request_sz);
 
         dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "request pool(0x%p): "
             "depth(%d), frame_size(%d), pool_size(%d kB)\n", ioc->name,
             ioc->request, ioc->hba_queue_depth, ioc->request_sz,
             (ioc->hba_queue_depth * ioc->request_sz)/1024));
-        dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "chain pool(0x%p): depth"
-            "(%d), frame_size(%d), pool_size(%d kB)\n", ioc->name, ioc->chain,
-            ioc->chain_depth, ioc->request_sz, ((ioc->chain_depth *
-            ioc->request_sz))/1024));
         dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "request pool: dma(0x%llx)\n",
             ioc->name, (unsigned long long) ioc->request_dma));
         total_sz += sz;
@@ -2255,6 +2269,38 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
             "depth(%d)\n", ioc->name, ioc->request,
             ioc->scsiio_depth));
 
+        /* loop till the allocation succeeds */
+        do {
+                sz = ioc->chain_depth * sizeof(struct chain_tracker);
+                ioc->chain_pages = get_order(sz);
+                ioc->chain_lookup = (struct chain_tracker *)__get_free_pages(
+                    GFP_KERNEL, ioc->chain_pages);
+                if (ioc->chain_lookup == NULL)
+                        ioc->chain_depth -= 100;
+        } while (ioc->chain_lookup == NULL);
+        ioc->chain_dma_pool = pci_pool_create("chain pool", ioc->pdev,
+            ioc->request_sz, 16, 0);
+        if (!ioc->chain_dma_pool) {
+                printk(MPT2SAS_ERR_FMT "chain_dma_pool: pci_pool_create "
+                    "failed\n", ioc->name);
+                goto out;
+        }
+        for (i = 0; i < ioc->chain_depth; i++) {
+                ioc->chain_lookup[i].chain_buffer = pci_pool_alloc(
+                    ioc->chain_dma_pool , GFP_KERNEL,
+                    &ioc->chain_lookup[i].chain_buffer_dma);
+                if (!ioc->chain_lookup[i].chain_buffer) {
+                        ioc->chain_depth = i;
+                        goto chain_done;
+                }
+                total_sz += ioc->request_sz;
+        }
+chain_done:
+        dinitprintk(ioc, printk(MPT2SAS_INFO_FMT "chain pool depth"
+            "(%d), frame_size(%d), pool_size(%d kB)\n", ioc->name,
+            ioc->chain_depth, ioc->request_sz, ((ioc->chain_depth *
+            ioc->request_sz))/1024));
+
         /* initialize hi-priority queue smid's */
         ioc->hpr_lookup = kcalloc(ioc->hi_priority_depth,
             sizeof(struct request_tracker), GFP_KERNEL);
@@ -2404,7 +2450,6 @@ _base_allocate_memory_pools(struct MPT2SAS_ADAPTER *ioc,  int sleep_flag)
         return 0;
 
  out:
-        _base_release_memory_pools(ioc);
         return -ENOMEM;
 }
 
@@ -3587,6 +3632,7 @@ _base_make_ioc_operational(struct MPT2SAS_ADAPTER *ioc, int sleep_flag)
         INIT_LIST_HEAD(&ioc->free_list);
         smid = 1;
         for (i = 0; i < ioc->scsiio_depth; i++, smid++) {
+                INIT_LIST_HEAD(&ioc->scsi_lookup[i].chain_list);
                 ioc->scsi_lookup[i].cb_idx = 0xFF;
                 ioc->scsi_lookup[i].smid = smid;
                 ioc->scsi_lookup[i].scmd = NULL;
@@ -3613,6 +3659,13 @@ _base_make_ioc_operational(struct MPT2SAS_ADAPTER *ioc, int sleep_flag)
                 list_add_tail(&ioc->internal_lookup[i].tracker_list,
                     &ioc->internal_free_list);
         }
+
+        /* chain pool */
+        INIT_LIST_HEAD(&ioc->free_chain_list);
+        for (i = 0; i < ioc->chain_depth; i++)
+                list_add_tail(&ioc->chain_lookup[i].tracker_list,
+                    &ioc->free_chain_list);
+
         spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
 
         /* initialize Reply Free Queue */
diff --git a/drivers/scsi/mpt2sas/mpt2sas_base.h b/drivers/scsi/mpt2sas/mpt2sas_base.h
index 63f7a196f42d..edf1a028db6c 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_base.h
+++ b/drivers/scsi/mpt2sas/mpt2sas_base.h
@@ -419,6 +419,18 @@ enum reset_type {
 };
 
 /**
+ * struct chain_tracker - firmware chain tracker
+ * @chain_buffer: chain buffer
+ * @chain_buffer_dma: physical address
+ * @tracker_list: list of free request (ioc->free_chain_list)
+ */
+struct chain_tracker {
+        void *chain_buffer;
+        dma_addr_t chain_buffer_dma;
+        struct list_head tracker_list;
+};
+
+/**
  * struct request_tracker - firmware request tracker
  * @smid: system message id
  * @scmd: scsi request pointer
@@ -430,6 +442,7 @@ struct request_tracker {
         u16     smid;
         struct scsi_cmnd *scmd;
         u8      cb_idx;
+        struct list_head chain_list;
         struct list_head tracker_list;
 };
 
@@ -704,8 +717,10 @@ struct MPT2SAS_ADAPTER {
         wait_queue_head_t reset_wq;
 
         /* chain */
-        u8              *chain;
-        dma_addr_t      chain_dma;
+        struct chain_tracker *chain_lookup;
+        struct list_head free_chain_list;
+        struct dma_pool *chain_dma_pool;
+        ulong           chain_pages;
         u16             max_sges_in_main_message;
         u16             max_sges_in_chain_message;
         u16             chains_needed_per_io;
diff --git a/drivers/scsi/mpt2sas/mpt2sas_scsih.c b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
index 5af5781d9464..3e9c78aa4ccb 100644
--- a/drivers/scsi/mpt2sas/mpt2sas_scsih.c
+++ b/drivers/scsi/mpt2sas/mpt2sas_scsih.c
@@ -931,31 +931,32 @@ _scsih_scsi_lookup_find_by_lun(struct MPT2SAS_ADAPTER *ioc, int id,
 }
 
 /**
- * _scsih_get_chain_buffer_dma - obtain block of chains (dma address)
+ * _scsih_get_chain_buffer_tracker - obtain chain tracker
  * @ioc: per adapter object
- * @smid: system request message index
+ * @smid: smid associated to an IO request
  *
- * Returns phys pointer to chain buffer.
+ * Returns chain tracker(from ioc->free_chain_list)
  */
-static dma_addr_t
-_scsih_get_chain_buffer_dma(struct MPT2SAS_ADAPTER *ioc, u16 smid)
+static struct chain_tracker *
+_scsih_get_chain_buffer_tracker(struct MPT2SAS_ADAPTER *ioc, u16 smid)
 {
-        return ioc->chain_dma + ((smid - 1) * (ioc->request_sz *
-            ioc->chains_needed_per_io));
-}
+        struct chain_tracker *chain_req;
+        unsigned long flags;
 
-/**
- * _scsih_get_chain_buffer - obtain block of chains assigned to a mf request
- * @ioc: per adapter object
- * @smid: system request message index
- *
- * Returns virt pointer to chain buffer.
- */
-static void *
-_scsih_get_chain_buffer(struct MPT2SAS_ADAPTER *ioc, u16 smid)
-{
-        return (void *)(ioc->chain + ((smid - 1) * (ioc->request_sz *
-            ioc->chains_needed_per_io)));
+        spin_lock_irqsave(&ioc->scsi_lookup_lock, flags);
+        if (list_empty(&ioc->free_chain_list)) {
+                spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
+                printk(MPT2SAS_WARN_FMT "chain buffers not available\n",
+                    ioc->name);
+                return NULL;
+        }
+        chain_req = list_entry(ioc->free_chain_list.next,
+            struct chain_tracker, tracker_list);
+        list_del_init(&chain_req->tracker_list);
+        list_add_tail(&chain_req->tracker_list,
+            &ioc->scsi_lookup[smid - 1].chain_list);
+        spin_unlock_irqrestore(&ioc->scsi_lookup_lock, flags);
+        return chain_req;
 }
 
 /**
@@ -986,6 +987,7 @@ _scsih_build_scatter_gather(struct MPT2SAS_ADAPTER *ioc,
         u32 sgl_flags;
         u32 sgl_flags_last_element;
         u32 sgl_flags_end_buffer;
+        struct chain_tracker *chain_req;
 
         mpi_request = mpt2sas_base_get_msg_frame(ioc, smid);
 
@@ -1033,8 +1035,11 @@ _scsih_build_scatter_gather(struct MPT2SAS_ADAPTER *ioc,
 
         /* initializing the chain flags and pointers */
         chain_flags = MPI2_SGE_FLAGS_CHAIN_ELEMENT << MPI2_SGE_FLAGS_SHIFT;
-        chain = _scsih_get_chain_buffer(ioc, smid);
-        chain_dma = _scsih_get_chain_buffer_dma(ioc, smid);
+        chain_req = _scsih_get_chain_buffer_tracker(ioc, smid);
+        if (!chain_req)
+                return -1;
+        chain = chain_req->chain_buffer;
+        chain_dma = chain_req->chain_buffer_dma;
         do {
                 sges_in_segment = (sges_left <=
                     ioc->max_sges_in_chain_message) ? sges_left :
@@ -1070,8 +1075,11 @@ _scsih_build_scatter_gather(struct MPT2SAS_ADAPTER *ioc,
                         sges_in_segment--;
                 }
 
-                chain_dma += ioc->request_sz;
-                chain += ioc->request_sz;
+                chain_req = _scsih_get_chain_buffer_tracker(ioc, smid);
+                if (!chain_req)
+                        return -1;
+                chain = chain_req->chain_buffer;
+                chain_dma = chain_req->chain_buffer_dma;
         } while (1);