/*
- * Copyright (c) 2006, Intel Corporation.
+ * Copyright © 2006-2009, Intel Corporation.
*
- * This file is released under the GPLv2.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
*
- * Copyright (C) 2006 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Author: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
*/
-#include "iova.h"
+#include <linux/iova.h>
void
-init_iova_domain(struct iova_domain *iovad)
+init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit)
{
- spin_lock_init(&iovad->iova_alloc_lock);
spin_lock_init(&iovad->iova_rbtree_lock);
iovad->rbroot = RB_ROOT;
iovad->cached32_node = NULL;
-
+ iovad->dma_32bit_pfn = pfn_32bit;
}
static struct rb_node *
__get_cached_rbnode(struct iova_domain *iovad, unsigned long *limit_pfn)
{
- if ((*limit_pfn != DMA_32BIT_PFN) ||
+ if ((*limit_pfn != iovad->dma_32bit_pfn) ||
(iovad->cached32_node == NULL))
return rb_last(&iovad->rbroot);
else {
__cached_rbnode_insert_update(struct iova_domain *iovad,
unsigned long limit_pfn, struct iova *new)
{
- if (limit_pfn != DMA_32BIT_PFN)
+ if (limit_pfn != iovad->dma_32bit_pfn)
return;
iovad->cached32_node = &new->node;
}
iovad->cached32_node = rb_next(&free->node);
}
-static int __alloc_iova_range(struct iova_domain *iovad,
- unsigned long size, unsigned long limit_pfn, struct iova *new)
+/* Computes the padding size required, to make the
+ * the start address naturally aligned on its size
+ */
+static int
+iova_get_pad_size(int size, unsigned int limit_pfn)
{
- struct rb_node *curr = NULL;
+ unsigned int pad_size = 0;
+ unsigned int order = ilog2(size);
+
+ if (order)
+ pad_size = (limit_pfn + 1) % (1 << order);
+
+ return pad_size;
+}
+
+static int __alloc_and_insert_iova_range(struct iova_domain *iovad,
+ unsigned long size, unsigned long limit_pfn,
+ struct iova *new, bool size_aligned)
+{
+ struct rb_node *prev, *curr = NULL;
unsigned long flags;
unsigned long saved_pfn;
+ unsigned int pad_size = 0;
/* Walk the tree backwards */
spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
saved_pfn = limit_pfn;
curr = __get_cached_rbnode(iovad, &limit_pfn);
+ prev = curr;
while (curr) {
struct iova *curr_iova = container_of(curr, struct iova, node);
+
if (limit_pfn < curr_iova->pfn_lo)
goto move_left;
- if (limit_pfn < curr_iova->pfn_hi)
+ else if (limit_pfn < curr_iova->pfn_hi)
goto adjust_limit_pfn;
- if ((curr_iova->pfn_hi + size) <= limit_pfn)
- break; /* found a free slot */
+ else {
+ if (size_aligned)
+ pad_size = iova_get_pad_size(size, limit_pfn);
+ if ((curr_iova->pfn_hi + size + pad_size) <= limit_pfn)
+ break; /* found a free slot */
+ }
adjust_limit_pfn:
limit_pfn = curr_iova->pfn_lo - 1;
move_left:
+ prev = curr;
curr = rb_prev(curr);
}
- if ((!curr) && !(IOVA_START_PFN + size <= limit_pfn)) {
- spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
- return -ENOMEM;
+ if (!curr) {
+ if (size_aligned)
+ pad_size = iova_get_pad_size(size, limit_pfn);
+ if ((IOVA_START_PFN + size + pad_size) > limit_pfn) {
+ spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+ return -ENOMEM;
+ }
}
- new->pfn_hi = limit_pfn;
- new->pfn_lo = limit_pfn - size + 1;
+
+ /* pfn_lo will point to size aligned address if size_aligned is set */
+ new->pfn_lo = limit_pfn - (size + pad_size) + 1;
+ new->pfn_hi = new->pfn_lo + size - 1;
+
+ /* Insert the new_iova into domain rbtree by holding writer lock */
+ /* Add new node and rebalance tree. */
+ {
+ struct rb_node **entry, *parent = NULL;
+
+ /* If we have 'prev', it's a valid place to start the
+ insertion. Otherwise, start from the root. */
+ if (prev)
+ entry = &prev;
+ else
+ entry = &iovad->rbroot.rb_node;
+
+ /* Figure out where to put new node */
+ while (*entry) {
+ struct iova *this = container_of(*entry,
+ struct iova, node);
+ parent = *entry;
+
+ if (new->pfn_lo < this->pfn_lo)
+ entry = &((*entry)->rb_left);
+ else if (new->pfn_lo > this->pfn_lo)
+ entry = &((*entry)->rb_right);
+ else
+ BUG(); /* this should not happen */
+ }
+
+ /* Add new node and rebalance tree. */
+ rb_link_node(&new->node, parent, entry);
+ rb_insert_color(&new->node, &iovad->rbroot);
+ }
+ __cached_rbnode_insert_update(iovad, saved_pfn, new);
spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
+
+
return 0;
}
* @iovad - iova domain in question
* @size - size of page frames to allocate
* @limit_pfn - max limit address
+ * @size_aligned - set if size_aligned address range is required
* This function allocates an iova in the range limit_pfn to IOVA_START_PFN
- * looking from limit_pfn instead from IOVA_START_PFN.
+ * looking from limit_pfn instead from IOVA_START_PFN. If the size_aligned
+ * flag is set then the allocated address iova->pfn_lo will be naturally
+ * aligned on roundup_power_of_two(size).
*/
struct iova *
alloc_iova(struct iova_domain *iovad, unsigned long size,
- unsigned long limit_pfn)
+ unsigned long limit_pfn,
+ bool size_aligned)
{
- unsigned long flags;
struct iova *new_iova;
int ret;
if (!new_iova)
return NULL;
- spin_lock_irqsave(&iovad->iova_alloc_lock, flags);
- ret = __alloc_iova_range(iovad, size, limit_pfn, new_iova);
+ /* If size aligned is set then round the size to
+ * to next power of two.
+ */
+ if (size_aligned)
+ size = __roundup_pow_of_two(size);
+
+ ret = __alloc_and_insert_iova_range(iovad, size, limit_pfn,
+ new_iova, size_aligned);
if (ret) {
- spin_unlock_irqrestore(&iovad->iova_alloc_lock, flags);
free_iova_mem(new_iova);
return NULL;
}
- /* Insert the new_iova into domain rbtree by holding writer lock */
- spin_lock(&iovad->iova_rbtree_lock);
- iova_insert_rbtree(&iovad->rbroot, new_iova);
- __cached_rbnode_insert_update(iovad, limit_pfn, new_iova);
- spin_unlock(&iovad->iova_rbtree_lock);
-
- spin_unlock_irqrestore(&iovad->iova_alloc_lock, flags);
-
return new_iova;
}
struct iova *iova;
unsigned int overlap = 0;
- spin_lock_irqsave(&iovad->iova_alloc_lock, flags);
- spin_lock(&iovad->iova_rbtree_lock);
+ spin_lock_irqsave(&iovad->iova_rbtree_lock, flags);
for (node = rb_first(&iovad->rbroot); node; node = rb_next(node)) {
if (__is_range_overlap(node, pfn_lo, pfn_hi)) {
iova = container_of(node, struct iova, node);
iova = __insert_new_range(iovad, pfn_lo, pfn_hi);
finish:
- spin_unlock(&iovad->iova_rbtree_lock);
- spin_unlock_irqrestore(&iovad->iova_alloc_lock, flags);
+ spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags);
return iova;
}
unsigned long flags;
struct rb_node *node;
- spin_lock_irqsave(&from->iova_alloc_lock, flags);
- spin_lock(&from->iova_rbtree_lock);
+ spin_lock_irqsave(&from->iova_rbtree_lock, flags);
for (node = rb_first(&from->rbroot); node; node = rb_next(node)) {
struct iova *iova = container_of(node, struct iova, node);
struct iova *new_iova;
printk(KERN_ERR "Reserve iova range %lx@%lx failed\n",
iova->pfn_lo, iova->pfn_lo);
}
- spin_unlock(&from->iova_rbtree_lock);
- spin_unlock_irqrestore(&from->iova_alloc_lock, flags);
+ spin_unlock_irqrestore(&from->iova_rbtree_lock, flags);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff