[PATCH] IB uverbs: add mthca user doorbell record support

Add support for userspace doorbell records to mthca.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/drivers/infiniband/hw/mthca/mthca_memfree.c b/drivers/infiniband/hw/mthca/mthca_memfree.c
index 6d3b05d..2a86461 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_memfree.c
+++ b/drivers/infiniband/hw/mthca/mthca_memfree.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Cisco Systems.  All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -47,6 +48,15 @@ enum {
        MTHCA_TABLE_CHUNK_SIZE = 1 << 18
 };
 
+struct mthca_user_db_table {
+       struct semaphore mutex;
+       struct {
+               u64                uvirt;
+               struct scatterlist mem;
+               int                refcount;
+       }                page[0];
+};
+
 void mthca_free_icm(struct mthca_dev *dev, struct mthca_icm *icm)
 {
        struct mthca_icm_chunk *chunk, *tmp;
@@ -344,13 +354,133 @@ void mthca_free_icm_table(struct mthca_dev *dev, struct mthca_icm_table *table)
        kfree(table);
 }
 
-static u64 mthca_uarc_virt(struct mthca_dev *dev, int page)
+static u64 mthca_uarc_virt(struct mthca_dev *dev, struct mthca_uar *uar, int page)
 {
        return dev->uar_table.uarc_base +
-               dev->driver_uar.index * dev->uar_table.uarc_size +
+               uar->index * dev->uar_table.uarc_size +
                page * 4096;
 }
 
+int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
+                     struct mthca_user_db_table *db_tab, int index, u64 uaddr)
+{
+       int ret = 0;
+       u8 status;
+       int i;
+
+       if (!mthca_is_memfree(dev))
+               return 0;
+
+       if (index < 0 || index > dev->uar_table.uarc_size / 8)
+               return -EINVAL;
+
+       down(&db_tab->mutex);
+
+       i = index / MTHCA_DB_REC_PER_PAGE;
+
+       if ((db_tab->page[i].refcount >= MTHCA_DB_REC_PER_PAGE)       ||
+           (db_tab->page[i].uvirt && db_tab->page[i].uvirt != uaddr) ||
+           (uaddr & 4095)) {
+               ret = -EINVAL;
+               goto out;
+       }
+
+       if (db_tab->page[i].refcount) {
+               ++db_tab->page[i].refcount;
+               goto out;
+       }
+
+       ret = get_user_pages(current, current->mm, uaddr & PAGE_MASK, 1, 1, 0,
+                            &db_tab->page[i].mem.page, NULL);
+       if (ret < 0)
+               goto out;
+
+       db_tab->page[i].mem.length = 4096;
+       db_tab->page[i].mem.offset = uaddr & ~PAGE_MASK;
+
+       ret = pci_map_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
+       if (ret < 0) {
+               put_page(db_tab->page[i].mem.page);
+               goto out;
+       }
+
+       ret = mthca_MAP_ICM_page(dev, sg_dma_address(&db_tab->page[i].mem),
+                                mthca_uarc_virt(dev, uar, i), &status);
+       if (!ret && status)
+               ret = -EINVAL;
+       if (ret) {
+               pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
+               put_page(db_tab->page[i].mem.page);
+               goto out;
+       }
+
+       db_tab->page[i].uvirt    = uaddr;
+       db_tab->page[i].refcount = 1;
+
+out:
+       up(&db_tab->mutex);
+       return ret;
+}
+
+void mthca_unmap_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
+                        struct mthca_user_db_table *db_tab, int index)
+{
+       if (!mthca_is_memfree(dev))
+               return;
+
+       /*
+        * To make our bookkeeping simpler, we don't unmap DB
+        * pages until we clean up the whole db table.
+        */
+
+       down(&db_tab->mutex);
+
+       --db_tab->page[index / MTHCA_DB_REC_PER_PAGE].refcount;
+
+       up(&db_tab->mutex);
+}
+
+struct mthca_user_db_table *mthca_init_user_db_tab(struct mthca_dev *dev)
+{
+       struct mthca_user_db_table *db_tab;
+       int npages;
+       int i;
+
+       if (!mthca_is_memfree(dev))
+               return NULL;
+
+       npages = dev->uar_table.uarc_size / 4096;
+       db_tab = kmalloc(sizeof *db_tab + npages * sizeof *db_tab->page, GFP_KERNEL);
+       if (!db_tab)
+               return ERR_PTR(-ENOMEM);
+
+       init_MUTEX(&db_tab->mutex);
+       for (i = 0; i < npages; ++i) {
+               db_tab->page[i].refcount = 0;
+               db_tab->page[i].uvirt    = 0;
+       }
+
+       return db_tab;
+}
+
+void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
+                              struct mthca_user_db_table *db_tab)
+{
+       int i;
+       u8 status;
+
+       if (!mthca_is_memfree(dev))
+               return;
+
+       for (i = 0; i < dev->uar_table.uarc_size / 4096; ++i) {
+               if (db_tab->page[i].uvirt) {
+                       mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, uar, i), 1, &status);
+                       pci_unmap_sg(dev->pdev, &db_tab->page[i].mem, 1, PCI_DMA_TODEVICE);
+                       put_page(db_tab->page[i].mem.page);
+               }
+       }
+}
+
 int mthca_alloc_db(struct mthca_dev *dev, int type, u32 qn, u32 **db)
 {
        int group;
@@ -407,7 +537,8 @@ int mthca_alloc_db(struct mthca_dev *dev, int type, u32 qn, u32 **db)
        }
        memset(page->db_rec, 0, 4096);
 
-       ret = mthca_MAP_ICM_page(dev, page->mapping, mthca_uarc_virt(dev, i), &status);
+       ret = mthca_MAP_ICM_page(dev, page->mapping,
+                                mthca_uarc_virt(dev, &dev->driver_uar, i), &status);
        if (!ret && status)
                ret = -EINVAL;
        if (ret) {
@@ -461,7 +592,7 @@ void mthca_free_db(struct mthca_dev *dev, int type, int db_index)
 
        if (bitmap_empty(page->used, MTHCA_DB_REC_PER_PAGE) &&
            i >= dev->db_tab->max_group1 - 1) {
-               mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, i), 1, &status);
+               mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 
                dma_free_coherent(&dev->pdev->dev, 4096,
                                  page->db_rec, page->mapping);
@@ -530,7 +661,7 @@ void mthca_cleanup_db_tab(struct mthca_dev *dev)
                if (!bitmap_empty(dev->db_tab->page[i].used, MTHCA_DB_REC_PER_PAGE))
                        mthca_warn(dev, "Kernel UARC page %d not empty\n", i);
 
-               mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, i), 1, &status);
+               mthca_UNMAP_ICM(dev, mthca_uarc_virt(dev, &dev->driver_uar, i), 1, &status);
 
                dma_free_coherent(&dev->pdev->dev, 4096,
                                  dev->db_tab->page[i].db_rec,

diff --git a/drivers/infiniband/hw/mthca/mthca_memfree.h b/drivers/infiniband/hw/mthca/mthca_memfree.h
index fe7be2a..4761d84 100644 (file)
--- a/drivers/infiniband/hw/mthca/mthca_memfree.h
+++ b/drivers/infiniband/hw/mthca/mthca_memfree.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2004, 2005 Topspin Communications.  All rights reserved.
+ * Copyright (c) 2005 Cisco Systems.  All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
@@ -148,7 +149,7 @@ struct mthca_db_table {
        struct semaphore      mutex;
 };
 
-enum {
+enum mthca_db_type {
        MTHCA_DB_TYPE_INVALID   = 0x0,
        MTHCA_DB_TYPE_CQ_SET_CI = 0x1,
        MTHCA_DB_TYPE_CQ_ARM    = 0x2,
@@ -158,6 +159,17 @@ enum {
        MTHCA_DB_TYPE_GROUP_SEP = 0x7
 };
 
+struct mthca_user_db_table;
+struct mthca_uar;
+
+int mthca_map_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
+                     struct mthca_user_db_table *db_tab, int index, u64 uaddr);
+void mthca_unmap_user_db(struct mthca_dev *dev, struct mthca_uar *uar,
+                        struct mthca_user_db_table *db_tab, int index);
+struct mthca_user_db_table *mthca_init_user_db_tab(struct mthca_dev *dev);
+void mthca_cleanup_user_db_tab(struct mthca_dev *dev, struct mthca_uar *uar,
+                              struct mthca_user_db_table *db_tab);
+
 int mthca_init_db_tab(struct mthca_dev *dev);
 void mthca_cleanup_db_tab(struct mthca_dev *dev);
 int mthca_alloc_db(struct mthca_dev *dev, int type, u32 qn, u32 **db);