[PATCH][17/27] IB/mthca: encapsulate MTT buddy allocator

Roland Dreier
2005-04-01T21:45:48Z

From: Michael S. Tsirkin <mst@mellanox.co.il>

Encapsulate the buddy allocator used for MTT segments. This cleans up
the code and also gets us ready to add FMR support.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <roland@topspin.com>

--- linux-export.orig/drivers/infiniband/hw/mthca/mthca_dev.h 2005-04-01 12:38:26.173279180 -0800
+++ linux-export/drivers/infiniband/hw/mthca/mthca_dev.h 2005-04-01 12:38:27.068084943 -0800
@@ -170,10 +170,15 @@
struct mthca_alloc alloc;
};

+struct mthca_buddy {
+ unsigned long **bits;
+ int max_order;
+ spinlock_t lock;
+};
+
struct mthca_mr_table {
struct mthca_alloc mpt_alloc;
- int max_mtt_order;
- unsigned long **mtt_buddy;
+ struct mthca_buddy mtt_buddy;
u64 mtt_base;
struct mthca_icm_table *mtt_table;
struct mthca_icm_table *mpt_table;
--- linux-export.orig/drivers/infiniband/hw/mthca/mthca_mr.c 2005-04-01 12:38:25.582407442 -0800
+++ linux-export/drivers/infiniband/hw/mthca/mthca_mr.c 2005-04-01 12:38:27.075083423 -0800
@@ -72,60 +72,108 @@
* through the bitmaps)
*/

-static u32 __mthca_alloc_mtt(struct mthca_dev *dev, int order)
+static u32 mthca_buddy_alloc(struct mthca_buddy *buddy, int order)
{
int o;
int m;
u32 seg;

- spin_lock(&dev->mr_table.mpt_alloc.lock);
+ spin_lock(&buddy->lock);

- for (o = order; o <= dev->mr_table.max_mtt_order; ++o) {
- m = 1 << (dev->mr_table.max_mtt_order - o);
- seg = find_first_bit(dev->mr_table.mtt_buddy[o], m);
+ for (o = order; o <= buddy->max_order; ++o) {
+ m = 1 << (buddy->max_order - o);
+ seg = find_first_bit(buddy->bits[o], m);
if (seg < m)
goto found;
}

- spin_unlock(&dev->mr_table.mpt_alloc.lock);
+ spin_unlock(&buddy->lock);
return -1;

found:
- clear_bit(seg, dev->mr_table.mtt_buddy[o]);
+ clear_bit(seg, buddy->bits[o]);

while (o > order) {
--o;
seg <<= 1;
- set_bit(seg ^ 1, dev->mr_table.mtt_buddy[o]);
+ set_bit(seg ^ 1, buddy->bits[o]);
}

- spin_unlock(&dev->mr_table.mpt_alloc.lock);
+ spin_unlock(&buddy->lock);

seg <<= order;

return seg;
}

-static void __mthca_free_mtt(struct mthca_dev *dev, u32 seg, int order)
+static void mthca_buddy_free(struct mthca_buddy *buddy, u32 seg, int order)
{
seg >>= order;

- spin_lock(&dev->mr_table.mpt_alloc.lock);
+ spin_lock(&buddy->lock);

- while (test_bit(seg ^ 1, dev->mr_table.mtt_buddy[order])) {
- clear_bit(seg ^ 1, dev->mr_table.mtt_buddy[order]);
+ while (test_bit(seg ^ 1, buddy->bits[order])) {
+ clear_bit(seg ^ 1, buddy->bits[order]);
seg >>= 1;
++order;
}

- set_bit(seg, dev->mr_table.mtt_buddy[order]);
+ set_bit(seg, buddy->bits[order]);

- spin_unlock(&dev->mr_table.mpt_alloc.lock);
+ spin_unlock(&buddy->lock);
}

-static u32 mthca_alloc_mtt(struct mthca_dev *dev, int order)
+static int __devinit mthca_buddy_init(struct mthca_buddy *buddy, int max_order)
{
- u32 seg = __mthca_alloc_mtt(dev, order);
+ int i, s;
+
+ buddy->max_order = max_order;
+ spin_lock_init(&buddy->lock);
+
+ buddy->bits = kmalloc((buddy->max_order + 1) * sizeof (long *),
+ GFP_KERNEL);
+ if (!buddy->bits)
+ goto err_out;
+
+ memset(buddy->bits, 0, (buddy->max_order + 1) * sizeof (long *));
+
+ for (i = 0; i <= buddy->max_order; ++i) {
+ s = BITS_TO_LONGS(1 << (buddy->max_order - i));
+ buddy->bits[i] = kmalloc(s * sizeof (long), GFP_KERNEL);
+ if (!buddy->bits[i])
+ goto err_out_free;
+ bitmap_zero(buddy->bits[i],
+ 1 << (buddy->max_order - i));
+ }
+
+ set_bit(0, buddy->bits[buddy->max_order]);
+
+ return 0;
+
+err_out_free:
+ for (i = 0; i <= buddy->max_order; ++i)
+ kfree(buddy->bits[i]);
+
+ kfree(buddy->bits);
+
+err_out:
+ return -ENOMEM;
+}
+
+static void __devexit mthca_buddy_cleanup(struct mthca_buddy *buddy)
+{
+ int i;
+
+ for (i = 0; i <= buddy->max_order; ++i)
+ kfree(buddy->bits[i]);
+
+ kfree(buddy->bits);
+}
+
+static u32 mthca_alloc_mtt(struct mthca_dev *dev, int order,
+ struct mthca_buddy *buddy)
+{
+ u32 seg = mthca_buddy_alloc(buddy, order);

if (seg == -1)
return -1;
@@ -133,16 +181,17 @@
if (dev->hca_type == ARBEL_NATIVE)
if (mthca_table_get_range(dev, dev->mr_table.mtt_table, seg,
seg + (1 << order) - 1)) {
- __mthca_free_mtt(dev, seg, order);
+ mthca_buddy_free(buddy, seg, order);
seg = -1;
}

return seg;
}

-static void mthca_free_mtt(struct mthca_dev *dev, u32 seg, int order)
+static void mthca_free_mtt(struct mthca_dev *dev, u32 seg, int order,
+ struct mthca_buddy* buddy)
{
- __mthca_free_mtt(dev, seg, order);
+ mthca_buddy_free(buddy, seg, order);

if (dev->hca_type == ARBEL_NATIVE)
mthca_table_put_range(dev, dev->mr_table.mtt_table, seg,
@@ -268,7 +317,8 @@
i <<= 1, ++mr->order)
; /* nothing */

- mr->first_seg = mthca_alloc_mtt(dev, mr->order);
+ mr->first_seg = mthca_alloc_mtt(dev, mr->order,
+ &dev->mr_table.mtt_buddy);
if (mr->first_seg == -1)
goto err_out_table;

@@ -361,7 +411,7 @@
kfree(mailbox);

err_out_free_mtt:
- mthca_free_mtt(dev, mr->first_seg, mr->order);
+ mthca_free_mtt(dev, mr->first_seg, mr->order, &dev->mr_table.mtt_buddy);

err_out_table:
if (dev->hca_type == ARBEL_NATIVE)
@@ -390,7 +440,7 @@
status);

if (mr->order >= 0)
- mthca_free_mtt(dev, mr->first_seg, mr->order);
+ mthca_free_mtt(dev, mr->first_seg, mr->order, &dev->mr_table.mtt_buddy);

if (dev->hca_type == ARBEL_NATIVE)
mthca_table_put(dev, dev->mr_table.mpt_table,
@@ -401,7 +451,6 @@
int __devinit mthca_init_mr_table(struct mthca_dev *dev)
{
int err;
- int i, s;

err = mthca_alloc_init(&dev->mr_table.mpt_alloc,
dev->limits.num_mpts,
@@ -409,53 +458,24 @@
if (err)
return err;

- err = -ENOMEM;
-
- for (i = 1, dev->mr_table.max_mtt_order = 0;
- i < dev->limits.num_mtt_segs;
- i <<= 1, ++dev->mr_table.max_mtt_order)
- ; /* nothing */
-
- dev->mr_table.mtt_buddy = kmalloc((dev->mr_table.max_mtt_order + 1) *
- sizeof (long *),
- GFP_KERNEL);
- if (!dev->mr_table.mtt_buddy)
- goto err_out;
-
- for (i = 0; i <= dev->mr_table.max_mtt_order; ++i)
- dev->mr_table.mtt_buddy[i] = NULL;
-
- for (i = 0; i <= dev->mr_table.max_mtt_order; ++i) {
- s = BITS_TO_LONGS(1 << (dev->mr_table.max_mtt_order - i));
- dev->mr_table.mtt_buddy[i] = kmalloc(s * sizeof (long),
- GFP_KERNEL);
- if (!dev->mr_table.mtt_buddy[i])
- goto err_out_free;
- bitmap_zero(dev->mr_table.mtt_buddy[i],
- 1 << (dev->mr_table.max_mtt_order - i));
- }
-
- set_bit(0, dev->mr_table.mtt_buddy[dev->mr_table.max_mtt_order]);
-
- for (i = 0; i < dev->mr_table.max_mtt_order; ++i)
- if (1 << i >= dev->limits.reserved_mtts)
- break;
+ err = mthca_buddy_init(&dev->mr_table.mtt_buddy,
+ fls(dev->limits.num_mtt_segs - 1));
+ if (err)
+ goto err_mtt_buddy;

- if (i == dev->mr_table.max_mtt_order) {
- mthca_err(dev, "MTT table of order %d is "
- "too small.\n", i);
- goto err_out_free;
+ if (dev->limits.reserved_mtts) {
+ if (mthca_alloc_mtt(dev, fls(dev->limits.reserved_mtts - 1),
+ &dev->mr_table.mtt_buddy) == -1) {
+ mthca_warn(dev, "MTT table of order %d is too small.\n",
+ dev->mr_table.mtt_buddy.max_order);
+ err = -ENOMEM;
+ goto err_mtt_buddy;
+ }
}

- (void) mthca_alloc_mtt(dev, i);
-
return 0;

- err_out_free:
- for (i = 0; i <= dev->mr_table.max_mtt_order; ++i)
- kfree(dev->mr_table.mtt_buddy[i]);
-
- err_out:
+err_mtt_buddy:
mthca_alloc_cleanup(&dev->mr_table.mpt_alloc);

return err;
@@ -463,11 +483,7 @@

void __devexit mthca_cleanup_mr_table(struct mthca_dev *dev)
{
- int i;
-
/* XXX check if any MRs are still allocated? */
- for (i = 0; i <= dev->mr_table.max_mtt_order; ++i)
- kfree(dev->mr_table.mtt_buddy[i]);
- kfree(dev->mr_table.mtt_buddy);
+ mthca_buddy_cleanup(&dev->mr_table.mtt_buddy);
mthca_alloc_cleanup(&dev->mr_table.mpt_alloc);
}