[PATCH] IB/mthca: Split off MTT allocation

Split allocation of MTT range from creation of MR.  This will be useful for
implementing shared memory regions and userspace verbs.

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

3 files changed, 177 insertions, 168 deletions

diff --git a/drivers/infiniband/hw/mthca/mthca_dev.h b/drivers/infiniband/hw/mthca/mthca_dev.h
index df26d818c1ce..e8cf4d68d11c 100644
--- a/drivers/infiniband/hw/mthca/mthca_dev.h
+++ b/drivers/infiniband/hw/mthca/mthca_dev.h
@@ -380,6 +380,12 @@ void mthca_uar_free(struct mthca_dev *dev, struct mthca_uar *uar);
 int mthca_pd_alloc(struct mthca_dev *dev, struct mthca_pd *pd);
 void mthca_pd_free(struct mthca_dev *dev, struct mthca_pd *pd);
 
+struct mthca_mtt *mthca_alloc_mtt(struct mthca_dev *dev, int size);
+void mthca_free_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt);
+int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                    int start_index, u64 *buffer_list, int list_len);
+int mthca_mr_alloc(struct mthca_dev *dev, u32 pd, int buffer_size_shift,
+                   u64 iova, u64 total_size, u32 access, struct mthca_mr *mr);
 int mthca_mr_alloc_notrans(struct mthca_dev *dev, u32 pd,
                            u32 access, struct mthca_mr *mr);
 int mthca_mr_alloc_phys(struct mthca_dev *dev, u32 pd,
diff --git a/drivers/infiniband/hw/mthca/mthca_mr.c b/drivers/infiniband/hw/mthca/mthca_mr.c
index 29e5fe708b83..877654ae42da 100644
--- a/drivers/infiniband/hw/mthca/mthca_mr.c
+++ b/drivers/infiniband/hw/mthca/mthca_mr.c
@@ -40,6 +40,12 @@
 #include "mthca_cmd.h"
 #include "mthca_memfree.h"
 
+struct mthca_mtt {
+        struct mthca_buddy *buddy;
+        int                 order;
+        u32                 first_seg;
+};
+
 /*
  * Must be packed because mtt_seg is 64 bits but only aligned to 32 bits.
  */
@@ -173,8 +179,8 @@ static void __devexit mthca_buddy_cleanup(struct mthca_buddy *buddy)
         kfree(buddy->bits);
 }
 
-static u32 mthca_alloc_mtt(struct mthca_dev *dev, int order,
-                           struct mthca_buddy *buddy)
+static u32 mthca_alloc_mtt_range(struct mthca_dev *dev, int order,
+                                 struct mthca_buddy *buddy)
 {
         u32 seg = mthca_buddy_alloc(buddy, order);
 
@@ -191,12 +197,100 @@ static u32 mthca_alloc_mtt(struct mthca_dev *dev, int order,
         return seg;
 }
 
-static void mthca_free_mtt(struct mthca_dev *dev, u32 seg, int order,
-                           struct mthca_buddy* buddy)
+static struct mthca_mtt *__mthca_alloc_mtt(struct mthca_dev *dev, int size,
+                                           struct mthca_buddy *buddy)
+{
+        struct mthca_mtt *mtt;
+        int i;
+
+        if (size <= 0)
+                return ERR_PTR(-EINVAL);
+
+        mtt = kmalloc(sizeof *mtt, GFP_KERNEL);
+        if (!mtt)
+                return ERR_PTR(-ENOMEM);
+
+        mtt->buddy = buddy;
+        mtt->order = 0;
+        for (i = MTHCA_MTT_SEG_SIZE / 8; i < size; i <<= 1)
+                ++mtt->order;
+
+        mtt->first_seg = mthca_alloc_mtt_range(dev, mtt->order, buddy);
+        if (mtt->first_seg == -1) {
+                kfree(mtt);
+                return ERR_PTR(-ENOMEM);
+        }
+
+        return mtt;
+}
+
+struct mthca_mtt *mthca_alloc_mtt(struct mthca_dev *dev, int size)
+{
+        return __mthca_alloc_mtt(dev, size, &dev->mr_table.mtt_buddy);
+}
+
+void mthca_free_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt)
+{
+        if (!mtt)
+                return;
+
+        mthca_buddy_free(mtt->buddy, mtt->first_seg, mtt->order);
+
+        mthca_table_put_range(dev, dev->mr_table.mtt_table,
+                              mtt->first_seg,
+                              mtt->first_seg + (1 << mtt->order) - 1);
+
+        kfree(mtt);
+}
+
+int mthca_write_mtt(struct mthca_dev *dev, struct mthca_mtt *mtt,
+                    int start_index, u64 *buffer_list, int list_len)
 {
-        mthca_buddy_free(buddy, seg, order);
-        mthca_table_put_range(dev, dev->mr_table.mtt_table, seg,
-                              seg + (1 << order) - 1);
+        u64 *mtt_entry;
+        int err = 0;
+        u8 status;
+        int i;
+
+        mtt_entry = (u64 *) __get_free_page(GFP_KERNEL);
+        if (!mtt_entry)
+                return -ENOMEM;
+
+        while (list_len > 0) {
+                mtt_entry[0] = cpu_to_be64(dev->mr_table.mtt_base +
+                                           mtt->first_seg * MTHCA_MTT_SEG_SIZE +
+                                           start_index * 8);
+                mtt_entry[1] = 0;
+                for (i = 0; i < list_len && i < PAGE_SIZE / 8 - 2; ++i)
+                        mtt_entry[i + 2] = cpu_to_be64(buffer_list[i] |
+                                                       MTHCA_MTT_FLAG_PRESENT);
+
+                /*
+                 * If we have an odd number of entries to write, add
+                 * one more dummy entry for firmware efficiency.
+                 */
+                if (i & 1)
+                        mtt_entry[i + 2] = 0;
+
+                err = mthca_WRITE_MTT(dev, mtt_entry, (i + 1) & ~1, &status);
+                if (err) {
+                        mthca_warn(dev, "WRITE_MTT failed (%d)\n", err);
+                        goto out;
+                }
+                if (status) {
+                        mthca_warn(dev, "WRITE_MTT returned status 0x%02x\n",
+                                   status);
+                        err = -EINVAL;
+                        goto out;
+                }
+
+                list_len    -= i;
+                start_index += i;
+                buffer_list += i;
+        }
+
+out:
+        free_page((unsigned long) mtt_entry);
+        return err;
 }
 
 static inline u32 tavor_hw_index_to_key(u32 ind)
@@ -235,18 +329,20 @@ static inline u32 key_to_hw_index(struct mthca_dev *dev, u32 key)
                 return tavor_key_to_hw_index(key);
 }
 
-int mthca_mr_alloc_notrans(struct mthca_dev *dev, u32 pd,
-                           u32 access, struct mthca_mr *mr)
+int mthca_mr_alloc(struct mthca_dev *dev, u32 pd, int buffer_size_shift,
+                   u64 iova, u64 total_size, u32 access, struct mthca_mr *mr)
 {
-        void *mailbox = NULL;
+        void *mailbox;
         struct mthca_mpt_entry *mpt_entry;
         u32 key;
+        int i;
         int err;
         u8 status;
 
         might_sleep();
 
-        mr->order = -1;
+        WARN_ON(buffer_size_shift >= 32);
+
         key = mthca_alloc(&dev->mr_table.mpt_alloc);
         if (key == -1)
                 return -ENOMEM;
@@ -268,186 +364,98 @@ int mthca_mr_alloc_notrans(struct mthca_dev *dev, u32 pd,
 
         mpt_entry->flags = cpu_to_be32(MTHCA_MPT_FLAG_SW_OWNS     |
                                        MTHCA_MPT_FLAG_MIO         |
-                                       MTHCA_MPT_FLAG_PHYSICAL    |
                                        MTHCA_MPT_FLAG_REGION      |
                                        access);
-        mpt_entry->page_size = 0;
+        if (!mr->mtt)
+                mpt_entry->flags |= cpu_to_be32(MTHCA_MPT_FLAG_PHYSICAL);
+
+        mpt_entry->page_size = cpu_to_be32(buffer_size_shift - 12);
         mpt_entry->key       = cpu_to_be32(key);
         mpt_entry->pd        = cpu_to_be32(pd);
-        mpt_entry->start     = 0;
-        mpt_entry->length    = ~0ULL;
+        mpt_entry->start     = cpu_to_be64(iova);
+        mpt_entry->length    = cpu_to_be64(total_size);
 
         memset(&mpt_entry->lkey, 0,
                sizeof *mpt_entry - offsetof(struct mthca_mpt_entry, lkey));
 
+        if (mr->mtt)
+                mpt_entry->mtt_seg =
+                        cpu_to_be64(dev->mr_table.mtt_base +
+                                    mr->mtt->first_seg * MTHCA_MTT_SEG_SIZE);
+
+        if (0) {
+                mthca_dbg(dev, "Dumping MPT entry %08x:\n", mr->ibmr.lkey);
+                for (i = 0; i < sizeof (struct mthca_mpt_entry) / 4; ++i) {
+                        if (i % 4 == 0)
+                                printk("[%02x] ", i * 4);
+                        printk(" %08x", be32_to_cpu(((u32 *) mpt_entry)[i]));
+                        if ((i + 1) % 4 == 0)
+                                printk("\n");
+                }
+        }
+
         err = mthca_SW2HW_MPT(dev, mpt_entry,
                               key & (dev->limits.num_mpts - 1),
                               &status);
         if (err) {
                 mthca_warn(dev, "SW2HW_MPT failed (%d)\n", err);
-                goto err_out_table;
+                goto err_out_mailbox;
         } else if (status) {
                 mthca_warn(dev, "SW2HW_MPT returned status 0x%02x\n",
                            status);
                 err = -EINVAL;
-                goto err_out_table;
+                goto err_out_mailbox;
         }
 
         kfree(mailbox);
         return err;
 
+err_out_mailbox:
+        kfree(mailbox);
+
 err_out_table:
         mthca_table_put(dev, dev->mr_table.mpt_table, key);
 
 err_out_mpt_free:
         mthca_free(&dev->mr_table.mpt_alloc, key);
-        kfree(mailbox);
         return err;
 }
 
+int mthca_mr_alloc_notrans(struct mthca_dev *dev, u32 pd,
+                           u32 access, struct mthca_mr *mr)
+{
+        mr->mtt = NULL;
+        return mthca_mr_alloc(dev, pd, 12, 0, ~0ULL, access, mr);
+}
+
 int mthca_mr_alloc_phys(struct mthca_dev *dev, u32 pd,
                         u64 *buffer_list, int buffer_size_shift,
                         int list_len, u64 iova, u64 total_size,
                         u32 access, struct mthca_mr *mr)
 {
-        void *mailbox;
-        u64 *mtt_entry;
-        struct mthca_mpt_entry *mpt_entry;
-        u32 key;
-        int err = -ENOMEM;
-        u8 status;
-        int i;
-
-        might_sleep();
-        WARN_ON(buffer_size_shift >= 32);
-
-        key = mthca_alloc(&dev->mr_table.mpt_alloc);
-        if (key == -1)
-                return -ENOMEM;
-        mr->ibmr.rkey = mr->ibmr.lkey = hw_index_to_key(dev, key);
-
-        if (mthca_is_memfree(dev)) {
-                err = mthca_table_get(dev, dev->mr_table.mpt_table, key);
-                if (err)
-                        goto err_out_mpt_free;
-        }
-
-        for (i = MTHCA_MTT_SEG_SIZE / 8, mr->order = 0;
-             i < list_len;
-             i <<= 1, ++mr->order)
-                ; /* nothing */
-
-        mr->first_seg = mthca_alloc_mtt(dev, mr->order,
-                                        &dev->mr_table.mtt_buddy);
-        if (mr->first_seg == -1)
-                goto err_out_table;
-
-        /*
-         * If list_len is odd, we add one more dummy entry for
-         * firmware efficiency.
-         */
-        mailbox = kmalloc(max(sizeof *mpt_entry,
-                              (size_t) 8 * (list_len + (list_len & 1) + 2)) +
-                          MTHCA_CMD_MAILBOX_EXTRA,
-                          GFP_KERNEL);
-        if (!mailbox)
-                goto err_out_free_mtt;
-
-        mtt_entry = MAILBOX_ALIGN(mailbox);
-
-        mtt_entry[0] = cpu_to_be64(dev->mr_table.mtt_base +
-                                   mr->first_seg * MTHCA_MTT_SEG_SIZE);
-        mtt_entry[1] = 0;
-        for (i = 0; i < list_len; ++i)
-                mtt_entry[i + 2] = cpu_to_be64(buffer_list[i] |
-                                               MTHCA_MTT_FLAG_PRESENT);
-        if (list_len & 1) {
-                mtt_entry[i + 2] = 0;
-                ++list_len;
-        }
+        int err;
 
-        if (0) {
-                mthca_dbg(dev, "Dumping MPT entry\n");
-                for (i = 0; i < list_len + 2; ++i)
-                        printk(KERN_ERR "[%2d] %016llx\n",
-                               i, (unsigned long long) be64_to_cpu(mtt_entry[i]));
-        }
+        mr->mtt = mthca_alloc_mtt(dev, list_len);
+        if (IS_ERR(mr->mtt))
+                return PTR_ERR(mr->mtt);
 
-        err = mthca_WRITE_MTT(dev, mtt_entry, list_len, &status);
+        err = mthca_write_mtt(dev, mr->mtt, 0, buffer_list, list_len);
         if (err) {
-                mthca_warn(dev, "WRITE_MTT failed (%d)\n", err);
-                goto err_out_mailbox_free;
-        }
-        if (status) {
-                mthca_warn(dev, "WRITE_MTT returned status 0x%02x\n",
-                           status);
-                err = -EINVAL;
-                goto err_out_mailbox_free;
-        }
-
-        mpt_entry = MAILBOX_ALIGN(mailbox);
-
-        mpt_entry->flags = cpu_to_be32(MTHCA_MPT_FLAG_SW_OWNS     |
-                                       MTHCA_MPT_FLAG_MIO         |
-                                       MTHCA_MPT_FLAG_REGION      |
-                                       access);
-
-        mpt_entry->page_size = cpu_to_be32(buffer_size_shift - 12);
-        mpt_entry->key       = cpu_to_be32(key);
-        mpt_entry->pd        = cpu_to_be32(pd);
-        mpt_entry->start     = cpu_to_be64(iova);
-        mpt_entry->length    = cpu_to_be64(total_size);
-        memset(&mpt_entry->lkey, 0,
-               sizeof *mpt_entry - offsetof(struct mthca_mpt_entry, lkey));
-        mpt_entry->mtt_seg   = cpu_to_be64(dev->mr_table.mtt_base +
-                                           mr->first_seg * MTHCA_MTT_SEG_SIZE);
-
-        if (0) {
-                mthca_dbg(dev, "Dumping MPT entry %08x:\n", mr->ibmr.lkey);
-                for (i = 0; i < sizeof (struct mthca_mpt_entry) / 4; ++i) {
-                        if (i % 4 == 0)
-                                printk("[%02x] ", i * 4);
-                        printk(" %08x", be32_to_cpu(((u32 *) mpt_entry)[i]));
-                        if ((i + 1) % 4 == 0)
-                                printk("\n");
-                }
+                mthca_free_mtt(dev, mr->mtt);
+                return err;
         }
 
-        err = mthca_SW2HW_MPT(dev, mpt_entry,
-                              key & (dev->limits.num_mpts - 1),
-                              &status);
+        err = mthca_mr_alloc(dev, pd, buffer_size_shift, iova,
+                             total_size, access, mr);
         if (err)
-                mthca_warn(dev, "SW2HW_MPT failed (%d)\n", err);
-        else if (status) {
-                mthca_warn(dev, "SW2HW_MPT returned status 0x%02x\n",
-                           status);
-                err = -EINVAL;
-        }
+                mthca_free_mtt(dev, mr->mtt);
 
-        kfree(mailbox);
-        return err;
-
-err_out_mailbox_free:
-        kfree(mailbox);
-
-err_out_free_mtt:
-        mthca_free_mtt(dev, mr->first_seg, mr->order, &dev->mr_table.mtt_buddy);
-
-err_out_table:
-        mthca_table_put(dev, dev->mr_table.mpt_table, key);
-
-err_out_mpt_free:
-        mthca_free(&dev->mr_table.mpt_alloc, key);
         return err;
 }
 
 /* Free mr or fmr */
-static void mthca_free_region(struct mthca_dev *dev, u32 lkey, int order,
-                              u32 first_seg, struct mthca_buddy *buddy)
+static void mthca_free_region(struct mthca_dev *dev, u32 lkey)
 {
-        if (order >= 0)
-                mthca_free_mtt(dev, first_seg, order, buddy);
-
         mthca_table_put(dev, dev->mr_table.mpt_table,
                         arbel_key_to_hw_index(lkey));
 
@@ -471,8 +479,8 @@ void mthca_free_mr(struct mthca_dev *dev, struct mthca_mr *mr)
                 mthca_warn(dev, "HW2SW_MPT returned status 0x%02x\n",
                            status);
 
-        mthca_free_region(dev, mr->ibmr.lkey, mr->order, mr->first_seg,
-                          &dev->mr_table.mtt_buddy);
+        mthca_free_region(dev, mr->ibmr.lkey);
+        mthca_free_mtt(dev, mr->mtt);
 }
 
 int mthca_fmr_alloc(struct mthca_dev *dev, u32 pd,
@@ -517,21 +525,15 @@ int mthca_fmr_alloc(struct mthca_dev *dev, u32 pd,
                 mr->mem.tavor.mpt = dev->mr_table.tavor_fmr.mpt_base +
                         sizeof *(mr->mem.tavor.mpt) * idx;
 
-        for (i = MTHCA_MTT_SEG_SIZE / 8, mr->order = 0;
-             i < list_len;
-             i <<= 1, ++mr->order)
-                ; /* nothing */
-
-        mr->first_seg = mthca_alloc_mtt(dev, mr->order,
-                                        dev->mr_table.fmr_mtt_buddy);
-        if (mr->first_seg == -1)
+        mr->mtt = __mthca_alloc_mtt(dev, list_len, dev->mr_table.fmr_mtt_buddy);
+        if (IS_ERR(mr->mtt))
                 goto err_out_table;
 
-        mtt_seg = mr->first_seg * MTHCA_MTT_SEG_SIZE;
+        mtt_seg = mr->mtt->first_seg * MTHCA_MTT_SEG_SIZE;
 
         if (mthca_is_memfree(dev)) {
                 mr->mem.arbel.mtts = mthca_table_find(dev->mr_table.mtt_table,
-                                                      mr->first_seg);
+                                                      mr->mtt->first_seg);
                 BUG_ON(!mr->mem.arbel.mtts);
         } else
                 mr->mem.tavor.mtts = dev->mr_table.tavor_fmr.mtt_base + mtt_seg;
@@ -587,8 +589,7 @@ err_out_mailbox_free:
         kfree(mailbox);
 
 err_out_free_mtt:
-        mthca_free_mtt(dev, mr->first_seg, mr->order,
-                       dev->mr_table.fmr_mtt_buddy);
+        mthca_free_mtt(dev, mr->mtt);
 
 err_out_table:
         mthca_table_put(dev, dev->mr_table.mpt_table, key);
@@ -603,8 +604,9 @@ int mthca_free_fmr(struct mthca_dev *dev, struct mthca_fmr *fmr)
         if (fmr->maps)
                 return -EBUSY;
 
-        mthca_free_region(dev, fmr->ibmr.lkey, fmr->order, fmr->first_seg,
-                          dev->mr_table.fmr_mtt_buddy);
+        mthca_free_region(dev, fmr->ibmr.lkey);
+        mthca_free_mtt(dev, fmr->mtt);
+
         return 0;
 }
 
@@ -820,7 +822,8 @@ int __devinit mthca_init_mr_table(struct mthca_dev *dev)
         if (dev->limits.reserved_mtts) {
                 i = fls(dev->limits.reserved_mtts - 1);
 
-                if (mthca_alloc_mtt(dev, i, dev->mr_table.fmr_mtt_buddy) == -1) {
+                if (mthca_alloc_mtt_range(dev, i,
+                                          dev->mr_table.fmr_mtt_buddy) == -1) {
                         mthca_warn(dev, "MTT table of order %d is too small.\n",
                                   dev->mr_table.fmr_mtt_buddy->max_order);
                         err = -ENOMEM;
diff --git a/drivers/infiniband/hw/mthca/mthca_provider.h b/drivers/infiniband/hw/mthca/mthca_provider.h
index 619710f95a87..4d976cccb1a8 100644
--- a/drivers/infiniband/hw/mthca/mthca_provider.h
+++ b/drivers/infiniband/hw/mthca/mthca_provider.h
@@ -54,18 +54,18 @@ struct mthca_uar {
         int           index;
 };
 
+struct mthca_mtt;
+
 struct mthca_mr {
-        struct ib_mr ibmr;
-        int order;
-        u32 first_seg;
+        struct ib_mr      ibmr;
+        struct mthca_mtt *mtt;
 };
 
 struct mthca_fmr {
-        struct ib_fmr ibmr;
+        struct ib_fmr      ibmr;
         struct ib_fmr_attr attr;
-        int order;
-        u32 first_seg;
-        int maps;
+        struct mthca_mtt  *mtt;
+        int                maps;
         union {
                 struct {
                         struct mthca_mpt_entry __iomem *mpt;