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-rw-r--r--arch/powerpc/lib/rheap.c693
1 files changed, 693 insertions, 0 deletions
diff --git a/arch/powerpc/lib/rheap.c b/arch/powerpc/lib/rheap.c
new file mode 100644
index 000000000000..42c5de2c898f
--- /dev/null
+++ b/arch/powerpc/lib/rheap.c
@@ -0,0 +1,693 @@
+/*
+ * arch/ppc/syslib/rheap.c
+ *
+ * A Remote Heap. Remote means that we don't touch the memory that the
+ * heap points to. Normal heap implementations use the memory they manage
+ * to place their list. We cannot do that because the memory we manage may
+ * have special properties, for example it is uncachable or of different
+ * endianess.
+ *
+ * Author: Pantelis Antoniou <panto@intracom.gr>
+ *
+ * 2004 (c) INTRACOM S.A. Greece. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+
+#include <asm/rheap.h>
+
+/*
+ * Fixup a list_head, needed when copying lists. If the pointers fall
+ * between s and e, apply the delta. This assumes that
+ * sizeof(struct list_head *) == sizeof(unsigned long *).
+ */
+static inline void fixup(unsigned long s, unsigned long e, int d,
+ struct list_head *l)
+{
+ unsigned long *pp;
+
+ pp = (unsigned long *)&l->next;
+ if (*pp >= s && *pp < e)
+ *pp += d;
+
+ pp = (unsigned long *)&l->prev;
+ if (*pp >= s && *pp < e)
+ *pp += d;
+}
+
+/* Grow the allocated blocks */
+static int grow(rh_info_t * info, int max_blocks)
+{
+ rh_block_t *block, *blk;
+ int i, new_blocks;
+ int delta;
+ unsigned long blks, blke;
+
+ if (max_blocks <= info->max_blocks)
+ return -EINVAL;
+
+ new_blocks = max_blocks - info->max_blocks;
+
+ block = kmalloc(sizeof(rh_block_t) * max_blocks, GFP_KERNEL);
+ if (block == NULL)
+ return -ENOMEM;
+
+ if (info->max_blocks > 0) {
+
+ /* copy old block area */
+ memcpy(block, info->block,
+ sizeof(rh_block_t) * info->max_blocks);
+
+ delta = (char *)block - (char *)info->block;
+
+ /* and fixup list pointers */
+ blks = (unsigned long)info->block;
+ blke = (unsigned long)(info->block + info->max_blocks);
+
+ for (i = 0, blk = block; i < info->max_blocks; i++, blk++)
+ fixup(blks, blke, delta, &blk->list);
+
+ fixup(blks, blke, delta, &info->empty_list);
+ fixup(blks, blke, delta, &info->free_list);
+ fixup(blks, blke, delta, &info->taken_list);
+
+ /* free the old allocated memory */
+ if ((info->flags & RHIF_STATIC_BLOCK) == 0)
+ kfree(info->block);
+ }
+
+ info->block = block;
+ info->empty_slots += new_blocks;
+ info->max_blocks = max_blocks;
+ info->flags &= ~RHIF_STATIC_BLOCK;
+
+ /* add all new blocks to the free list */
+ for (i = 0, blk = block + info->max_blocks; i < new_blocks; i++, blk++)
+ list_add(&blk->list, &info->empty_list);
+
+ return 0;
+}
+
+/*
+ * Assure at least the required amount of empty slots. If this function
+ * causes a grow in the block area then all pointers kept to the block
+ * area are invalid!
+ */
+static int assure_empty(rh_info_t * info, int slots)
+{
+ int max_blocks;
+
+ /* This function is not meant to be used to grow uncontrollably */
+ if (slots >= 4)
+ return -EINVAL;
+
+ /* Enough space */
+ if (info->empty_slots >= slots)
+ return 0;
+
+ /* Next 16 sized block */
+ max_blocks = ((info->max_blocks + slots) + 15) & ~15;
+
+ return grow(info, max_blocks);
+}
+
+static rh_block_t *get_slot(rh_info_t * info)
+{
+ rh_block_t *blk;
+
+ /* If no more free slots, and failure to extend. */
+ /* XXX: You should have called assure_empty before */
+ if (info->empty_slots == 0) {
+ printk(KERN_ERR "rh: out of slots; crash is imminent.\n");
+ return NULL;
+ }
+
+ /* Get empty slot to use */
+ blk = list_entry(info->empty_list.next, rh_block_t, list);
+ list_del_init(&blk->list);
+ info->empty_slots--;
+
+ /* Initialize */
+ blk->start = NULL;
+ blk->size = 0;
+ blk->owner = NULL;
+
+ return blk;
+}
+
+static inline void release_slot(rh_info_t * info, rh_block_t * blk)
+{
+ list_add(&blk->list, &info->empty_list);
+ info->empty_slots++;
+}
+
+static void attach_free_block(rh_info_t * info, rh_block_t * blkn)
+{
+ rh_block_t *blk;
+ rh_block_t *before;
+ rh_block_t *after;
+ rh_block_t *next;
+ int size;
+ unsigned long s, e, bs, be;
+ struct list_head *l;
+
+ /* We assume that they are aligned properly */
+ size = blkn->size;
+ s = (unsigned long)blkn->start;
+ e = s + size;
+
+ /* Find the blocks immediately before and after the given one
+ * (if any) */
+ before = NULL;
+ after = NULL;
+ next = NULL;
+
+ list_for_each(l, &info->free_list) {
+ blk = list_entry(l, rh_block_t, list);
+
+ bs = (unsigned long)blk->start;
+ be = bs + blk->size;
+
+ if (next == NULL && s >= bs)
+ next = blk;
+
+ if (be == s)
+ before = blk;
+
+ if (e == bs)
+ after = blk;
+
+ /* If both are not null, break now */
+ if (before != NULL && after != NULL)
+ break;
+ }
+
+ /* Now check if they are really adjacent */
+ if (before != NULL && s != (unsigned long)before->start + before->size)
+ before = NULL;
+
+ if (after != NULL && e != (unsigned long)after->start)
+ after = NULL;
+
+ /* No coalescing; list insert and return */
+ if (before == NULL && after == NULL) {
+
+ if (next != NULL)
+ list_add(&blkn->list, &next->list);
+ else
+ list_add(&blkn->list, &info->free_list);
+
+ return;
+ }
+
+ /* We don't need it anymore */
+ release_slot(info, blkn);
+
+ /* Grow the before block */
+ if (before != NULL && after == NULL) {
+ before->size += size;
+ return;
+ }
+
+ /* Grow the after block backwards */
+ if (before == NULL && after != NULL) {
+ after->start = (int8_t *)after->start - size;
+ after->size += size;
+ return;
+ }
+
+ /* Grow the before block, and release the after block */
+ before->size += size + after->size;
+ list_del(&after->list);
+ release_slot(info, after);
+}
+
+static void attach_taken_block(rh_info_t * info, rh_block_t * blkn)
+{
+ rh_block_t *blk;
+ struct list_head *l;
+
+ /* Find the block immediately before the given one (if any) */
+ list_for_each(l, &info->taken_list) {
+ blk = list_entry(l, rh_block_t, list);
+ if (blk->start > blkn->start) {
+ list_add_tail(&blkn->list, &blk->list);
+ return;
+ }
+ }
+
+ list_add_tail(&blkn->list, &info->taken_list);
+}
+
+/*
+ * Create a remote heap dynamically. Note that no memory for the blocks
+ * are allocated. It will upon the first allocation
+ */
+rh_info_t *rh_create(unsigned int alignment)
+{
+ rh_info_t *info;
+
+ /* Alignment must be a power of two */
+ if ((alignment & (alignment - 1)) != 0)
+ return ERR_PTR(-EINVAL);
+
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (info == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ info->alignment = alignment;
+
+ /* Initially everything as empty */
+ info->block = NULL;
+ info->max_blocks = 0;
+ info->empty_slots = 0;
+ info->flags = 0;
+
+ INIT_LIST_HEAD(&info->empty_list);
+ INIT_LIST_HEAD(&info->free_list);
+ INIT_LIST_HEAD(&info->taken_list);
+
+ return info;
+}
+
+/*
+ * Destroy a dynamically created remote heap. Deallocate only if the areas
+ * are not static
+ */
+void rh_destroy(rh_info_t * info)
+{
+ if ((info->flags & RHIF_STATIC_BLOCK) == 0 && info->block != NULL)
+ kfree(info->block);
+
+ if ((info->flags & RHIF_STATIC_INFO) == 0)
+ kfree(info);
+}
+
+/*
+ * Initialize in place a remote heap info block. This is needed to support
+ * operation very early in the startup of the kernel, when it is not yet safe
+ * to call kmalloc.
+ */
+void rh_init(rh_info_t * info, unsigned int alignment, int max_blocks,
+ rh_block_t * block)
+{
+ int i;
+ rh_block_t *blk;
+
+ /* Alignment must be a power of two */
+ if ((alignment & (alignment - 1)) != 0)
+ return;
+
+ info->alignment = alignment;
+
+ /* Initially everything as empty */
+ info->block = block;
+ info->max_blocks = max_blocks;
+ info->empty_slots = max_blocks;
+ info->flags = RHIF_STATIC_INFO | RHIF_STATIC_BLOCK;
+
+ INIT_LIST_HEAD(&info->empty_list);
+ INIT_LIST_HEAD(&info->free_list);
+ INIT_LIST_HEAD(&info->taken_list);
+
+ /* Add all new blocks to the free list */
+ for (i = 0, blk = block; i < max_blocks; i++, blk++)
+ list_add(&blk->list, &info->empty_list);
+}
+
+/* Attach a free memory region, coalesces regions if adjuscent */
+int rh_attach_region(rh_info_t * info, void *start, int size)
+{
+ rh_block_t *blk;
+ unsigned long s, e, m;
+ int r;
+
+ /* The region must be aligned */
+ s = (unsigned long)start;
+ e = s + size;
+ m = info->alignment - 1;
+
+ /* Round start up */
+ s = (s + m) & ~m;
+
+ /* Round end down */
+ e = e & ~m;
+
+ /* Take final values */
+ start = (void *)s;
+ size = (int)(e - s);
+
+ /* Grow the blocks, if needed */
+ r = assure_empty(info, 1);
+ if (r < 0)
+ return r;
+
+ blk = get_slot(info);
+ blk->start = start;
+ blk->size = size;
+ blk->owner = NULL;
+
+ attach_free_block(info, blk);
+
+ return 0;
+}
+
+/* Detatch given address range, splits free block if needed. */
+void *rh_detach_region(rh_info_t * info, void *start, int size)
+{
+ struct list_head *l;
+ rh_block_t *blk, *newblk;
+ unsigned long s, e, m, bs, be;
+
+ /* Validate size */
+ if (size <= 0)
+ return ERR_PTR(-EINVAL);
+
+ /* The region must be aligned */
+ s = (unsigned long)start;
+ e = s + size;
+ m = info->alignment - 1;
+
+ /* Round start up */
+ s = (s + m) & ~m;
+
+ /* Round end down */
+ e = e & ~m;
+
+ if (assure_empty(info, 1) < 0)
+ return ERR_PTR(-ENOMEM);
+
+ blk = NULL;
+ list_for_each(l, &info->free_list) {
+ blk = list_entry(l, rh_block_t, list);
+ /* The range must lie entirely inside one free block */
+ bs = (unsigned long)blk->start;
+ be = (unsigned long)blk->start + blk->size;
+ if (s >= bs && e <= be)
+ break;
+ blk = NULL;
+ }
+
+ if (blk == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ /* Perfect fit */
+ if (bs == s && be == e) {
+ /* Delete from free list, release slot */
+ list_del(&blk->list);
+ release_slot(info, blk);
+ return (void *)s;
+ }
+
+ /* blk still in free list, with updated start and/or size */
+ if (bs == s || be == e) {
+ if (bs == s)
+ blk->start = (int8_t *)blk->start + size;
+ blk->size -= size;
+
+ } else {
+ /* The front free fragment */
+ blk->size = s - bs;
+
+ /* the back free fragment */
+ newblk = get_slot(info);
+ newblk->start = (void *)e;
+ newblk->size = be - e;
+
+ list_add(&newblk->list, &blk->list);
+ }
+
+ return (void *)s;
+}
+
+void *rh_alloc(rh_info_t * info, int size, const char *owner)
+{
+ struct list_head *l;
+ rh_block_t *blk;
+ rh_block_t *newblk;
+ void *start;
+
+ /* Validate size */
+ if (size <= 0)
+ return ERR_PTR(-EINVAL);
+
+ /* Align to configured alignment */
+ size = (size + (info->alignment - 1)) & ~(info->alignment - 1);
+
+ if (assure_empty(info, 1) < 0)
+ return ERR_PTR(-ENOMEM);
+
+ blk = NULL;
+ list_for_each(l, &info->free_list) {
+ blk = list_entry(l, rh_block_t, list);
+ if (size <= blk->size)
+ break;
+ blk = NULL;
+ }
+
+ if (blk == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ /* Just fits */
+ if (blk->size == size) {
+ /* Move from free list to taken list */
+ list_del(&blk->list);
+ blk->owner = owner;
+ start = blk->start;
+
+ attach_taken_block(info, blk);
+
+ return start;
+ }
+
+ newblk = get_slot(info);
+ newblk->start = blk->start;
+ newblk->size = size;
+ newblk->owner = owner;
+
+ /* blk still in free list, with updated start, size */
+ blk->start = (int8_t *)blk->start + size;
+ blk->size -= size;
+
+ start = newblk->start;
+
+ attach_taken_block(info, newblk);
+
+ return start;
+}
+
+/* allocate at precisely the given address */
+void *rh_alloc_fixed(rh_info_t * info, void *start, int size, const char *owner)
+{
+ struct list_head *l;
+ rh_block_t *blk, *newblk1, *newblk2;
+ unsigned long s, e, m, bs, be;
+
+ /* Validate size */
+ if (size <= 0)
+ return ERR_PTR(-EINVAL);
+
+ /* The region must be aligned */
+ s = (unsigned long)start;
+ e = s + size;
+ m = info->alignment - 1;
+
+ /* Round start up */
+ s = (s + m) & ~m;
+
+ /* Round end down */
+ e = e & ~m;
+
+ if (assure_empty(info, 2) < 0)
+ return ERR_PTR(-ENOMEM);
+
+ blk = NULL;
+ list_for_each(l, &info->free_list) {
+ blk = list_entry(l, rh_block_t, list);
+ /* The range must lie entirely inside one free block */
+ bs = (unsigned long)blk->start;
+ be = (unsigned long)blk->start + blk->size;
+ if (s >= bs && e <= be)
+ break;
+ }
+
+ if (blk == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ /* Perfect fit */
+ if (bs == s && be == e) {
+ /* Move from free list to taken list */
+ list_del(&blk->list);
+ blk->owner = owner;
+
+ start = blk->start;
+ attach_taken_block(info, blk);
+
+ return start;
+
+ }
+
+ /* blk still in free list, with updated start and/or size */
+ if (bs == s || be == e) {
+ if (bs == s)
+ blk->start = (int8_t *)blk->start + size;
+ blk->size -= size;
+
+ } else {
+ /* The front free fragment */
+ blk->size = s - bs;
+
+ /* The back free fragment */
+ newblk2 = get_slot(info);
+ newblk2->start = (void *)e;
+ newblk2->size = be - e;
+
+ list_add(&newblk2->list, &blk->list);
+ }
+
+ newblk1 = get_slot(info);
+ newblk1->start = (void *)s;
+ newblk1->size = e - s;
+ newblk1->owner = owner;
+
+ start = newblk1->start;
+ attach_taken_block(info, newblk1);
+
+ return start;
+}
+
+int rh_free(rh_info_t * info, void *start)
+{
+ rh_block_t *blk, *blk2;
+ struct list_head *l;
+ int size;
+
+ /* Linear search for block */
+ blk = NULL;
+ list_for_each(l, &info->taken_list) {
+ blk2 = list_entry(l, rh_block_t, list);
+ if (start < blk2->start)
+ break;
+ blk = blk2;
+ }
+
+ if (blk == NULL || start > (blk->start + blk->size))
+ return -EINVAL;
+
+ /* Remove from taken list */
+ list_del(&blk->list);
+
+ /* Get size of freed block */
+ size = blk->size;
+ attach_free_block(info, blk);
+
+ return size;
+}
+
+int rh_get_stats(rh_info_t * info, int what, int max_stats, rh_stats_t * stats)
+{
+ rh_block_t *blk;
+ struct list_head *l;
+ struct list_head *h;
+ int nr;
+
+ switch (what) {
+
+ case RHGS_FREE:
+ h = &info->free_list;
+ break;
+
+ case RHGS_TAKEN:
+ h = &info->taken_list;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ /* Linear search for block */
+ nr = 0;
+ list_for_each(l, h) {
+ blk = list_entry(l, rh_block_t, list);
+ if (stats != NULL && nr < max_stats) {
+ stats->start = blk->start;
+ stats->size = blk->size;
+ stats->owner = blk->owner;
+ stats++;
+ }
+ nr++;
+ }
+
+ return nr;
+}
+
+int rh_set_owner(rh_info_t * info, void *start, const char *owner)
+{
+ rh_block_t *blk, *blk2;
+ struct list_head *l;
+ int size;
+
+ /* Linear search for block */
+ blk = NULL;
+ list_for_each(l, &info->taken_list) {
+ blk2 = list_entry(l, rh_block_t, list);
+ if (start < blk2->start)
+ break;
+ blk = blk2;
+ }
+
+ if (blk == NULL || start > (blk->start + blk->size))
+ return -EINVAL;
+
+ blk->owner = owner;
+ size = blk->size;
+
+ return size;
+}
+
+void rh_dump(rh_info_t * info)
+{
+ static rh_stats_t st[32]; /* XXX maximum 32 blocks */
+ int maxnr;
+ int i, nr;
+
+ maxnr = sizeof(st) / sizeof(st[0]);
+
+ printk(KERN_INFO
+ "info @0x%p (%d slots empty / %d max)\n",
+ info, info->empty_slots, info->max_blocks);
+
+ printk(KERN_INFO " Free:\n");
+ nr = rh_get_stats(info, RHGS_FREE, maxnr, st);
+ if (nr > maxnr)
+ nr = maxnr;
+ for (i = 0; i < nr; i++)
+ printk(KERN_INFO
+ " 0x%p-0x%p (%u)\n",
+ st[i].start, (int8_t *) st[i].start + st[i].size,
+ st[i].size);
+ printk(KERN_INFO "\n");
+
+ printk(KERN_INFO " Taken:\n");
+ nr = rh_get_stats(info, RHGS_TAKEN, maxnr, st);
+ if (nr > maxnr)
+ nr = maxnr;
+ for (i = 0; i < nr; i++)
+ printk(KERN_INFO
+ " 0x%p-0x%p (%u) %s\n",
+ st[i].start, (int8_t *) st[i].start + st[i].size,
+ st[i].size, st[i].owner != NULL ? st[i].owner : "");
+ printk(KERN_INFO "\n");
+}
+
+void rh_dump_blk(rh_info_t * info, rh_block_t * blk)
+{
+ printk(KERN_INFO
+ "blk @0x%p: 0x%p-0x%p (%u)\n",
+ blk, blk->start, (int8_t *) blk->start + blk->size, blk->size);
+}