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-rw-r--r--arch/powerpc/mm/imalloc.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/arch/powerpc/mm/imalloc.c b/arch/powerpc/mm/imalloc.c
new file mode 100644
index 000000000000..c65b87b92756
--- /dev/null
+++ b/arch/powerpc/mm/imalloc.c
@@ -0,0 +1,317 @@
+/*
+ * c 2001 PPC 64 Team, IBM Corp
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/semaphore.h>
+#include <asm/imalloc.h>
+#include <asm/cacheflush.h>
+
+static DECLARE_MUTEX(imlist_sem);
+struct vm_struct * imlist = NULL;
+
+static int get_free_im_addr(unsigned long size, unsigned long *im_addr)
+{
+ unsigned long addr;
+ struct vm_struct **p, *tmp;
+
+ addr = ioremap_bot;
+ for (p = &imlist; (tmp = *p) ; p = &tmp->next) {
+ if (size + addr < (unsigned long) tmp->addr)
+ break;
+ if ((unsigned long)tmp->addr >= ioremap_bot)
+ addr = tmp->size + (unsigned long) tmp->addr;
+ if (addr >= IMALLOC_END-size)
+ return 1;
+ }
+ *im_addr = addr;
+
+ return 0;
+}
+
+/* Return whether the region described by v_addr and size is a subset
+ * of the region described by parent
+ */
+static inline int im_region_is_subset(unsigned long v_addr, unsigned long size,
+ struct vm_struct *parent)
+{
+ return (int) (v_addr >= (unsigned long) parent->addr &&
+ v_addr < (unsigned long) parent->addr + parent->size &&
+ size < parent->size);
+}
+
+/* Return whether the region described by v_addr and size is a superset
+ * of the region described by child
+ */
+static int im_region_is_superset(unsigned long v_addr, unsigned long size,
+ struct vm_struct *child)
+{
+ struct vm_struct parent;
+
+ parent.addr = (void *) v_addr;
+ parent.size = size;
+
+ return im_region_is_subset((unsigned long) child->addr, child->size,
+ &parent);
+}
+
+/* Return whether the region described by v_addr and size overlaps
+ * the region described by vm. Overlapping regions meet the
+ * following conditions:
+ * 1) The regions share some part of the address space
+ * 2) The regions aren't identical
+ * 3) Neither region is a subset of the other
+ */
+static int im_region_overlaps(unsigned long v_addr, unsigned long size,
+ struct vm_struct *vm)
+{
+ if (im_region_is_superset(v_addr, size, vm))
+ return 0;
+
+ return (v_addr + size > (unsigned long) vm->addr + vm->size &&
+ v_addr < (unsigned long) vm->addr + vm->size) ||
+ (v_addr < (unsigned long) vm->addr &&
+ v_addr + size > (unsigned long) vm->addr);
+}
+
+/* Determine imalloc status of region described by v_addr and size.
+ * Can return one of the following:
+ * IM_REGION_UNUSED - Entire region is unallocated in imalloc space.
+ * IM_REGION_SUBSET - Region is a subset of a region that is already
+ * allocated in imalloc space.
+ * vm will be assigned to a ptr to the parent region.
+ * IM_REGION_EXISTS - Exact region already allocated in imalloc space.
+ * vm will be assigned to a ptr to the existing imlist
+ * member.
+ * IM_REGION_OVERLAPS - Region overlaps an allocated region in imalloc space.
+ * IM_REGION_SUPERSET - Region is a superset of a region that is already
+ * allocated in imalloc space.
+ */
+static int im_region_status(unsigned long v_addr, unsigned long size,
+ struct vm_struct **vm)
+{
+ struct vm_struct *tmp;
+
+ for (tmp = imlist; tmp; tmp = tmp->next)
+ if (v_addr < (unsigned long) tmp->addr + tmp->size)
+ break;
+
+ if (tmp) {
+ if (im_region_overlaps(v_addr, size, tmp))
+ return IM_REGION_OVERLAP;
+
+ *vm = tmp;
+ if (im_region_is_subset(v_addr, size, tmp)) {
+ /* Return with tmp pointing to superset */
+ return IM_REGION_SUBSET;
+ }
+ if (im_region_is_superset(v_addr, size, tmp)) {
+ /* Return with tmp pointing to first subset */
+ return IM_REGION_SUPERSET;
+ }
+ else if (v_addr == (unsigned long) tmp->addr &&
+ size == tmp->size) {
+ /* Return with tmp pointing to exact region */
+ return IM_REGION_EXISTS;
+ }
+ }
+
+ *vm = NULL;
+ return IM_REGION_UNUSED;
+}
+
+static struct vm_struct * split_im_region(unsigned long v_addr,
+ unsigned long size, struct vm_struct *parent)
+{
+ struct vm_struct *vm1 = NULL;
+ struct vm_struct *vm2 = NULL;
+ struct vm_struct *new_vm = NULL;
+
+ vm1 = (struct vm_struct *) kmalloc(sizeof(*vm1), GFP_KERNEL);
+ if (vm1 == NULL) {
+ printk(KERN_ERR "%s() out of memory\n", __FUNCTION__);
+ return NULL;
+ }
+
+ if (v_addr == (unsigned long) parent->addr) {
+ /* Use existing parent vm_struct to represent child, allocate
+ * new one for the remainder of parent range
+ */
+ vm1->size = parent->size - size;
+ vm1->addr = (void *) (v_addr + size);
+ vm1->next = parent->next;
+
+ parent->size = size;
+ parent->next = vm1;
+ new_vm = parent;
+ } else if (v_addr + size == (unsigned long) parent->addr +
+ parent->size) {
+ /* Allocate new vm_struct to represent child, use existing
+ * parent one for remainder of parent range
+ */
+ vm1->size = size;
+ vm1->addr = (void *) v_addr;
+ vm1->next = parent->next;
+ new_vm = vm1;
+
+ parent->size -= size;
+ parent->next = vm1;
+ } else {
+ /* Allocate two new vm_structs for the new child and
+ * uppermost remainder, and use existing parent one for the
+ * lower remainder of parent range
+ */
+ vm2 = (struct vm_struct *) kmalloc(sizeof(*vm2), GFP_KERNEL);
+ if (vm2 == NULL) {
+ printk(KERN_ERR "%s() out of memory\n", __FUNCTION__);
+ kfree(vm1);
+ return NULL;
+ }
+
+ vm1->size = size;
+ vm1->addr = (void *) v_addr;
+ vm1->next = vm2;
+ new_vm = vm1;
+
+ vm2->size = ((unsigned long) parent->addr + parent->size) -
+ (v_addr + size);
+ vm2->addr = (void *) v_addr + size;
+ vm2->next = parent->next;
+
+ parent->size = v_addr - (unsigned long) parent->addr;
+ parent->next = vm1;
+ }
+
+ return new_vm;
+}
+
+static struct vm_struct * __add_new_im_area(unsigned long req_addr,
+ unsigned long size)
+{
+ struct vm_struct **p, *tmp, *area;
+
+ for (p = &imlist; (tmp = *p) ; p = &tmp->next) {
+ if (req_addr + size <= (unsigned long)tmp->addr)
+ break;
+ }
+
+ area = (struct vm_struct *) kmalloc(sizeof(*area), GFP_KERNEL);
+ if (!area)
+ return NULL;
+ area->flags = 0;
+ area->addr = (void *)req_addr;
+ area->size = size;
+ area->next = *p;
+ *p = area;
+
+ return area;
+}
+
+static struct vm_struct * __im_get_area(unsigned long req_addr,
+ unsigned long size,
+ int criteria)
+{
+ struct vm_struct *tmp;
+ int status;
+
+ status = im_region_status(req_addr, size, &tmp);
+ if ((criteria & status) == 0) {
+ return NULL;
+ }
+
+ switch (status) {
+ case IM_REGION_UNUSED:
+ tmp = __add_new_im_area(req_addr, size);
+ break;
+ case IM_REGION_SUBSET:
+ tmp = split_im_region(req_addr, size, tmp);
+ break;
+ case IM_REGION_EXISTS:
+ /* Return requested region */
+ break;
+ case IM_REGION_SUPERSET:
+ /* Return first existing subset of requested region */
+ break;
+ default:
+ printk(KERN_ERR "%s() unexpected imalloc region status\n",
+ __FUNCTION__);
+ tmp = NULL;
+ }
+
+ return tmp;
+}
+
+struct vm_struct * im_get_free_area(unsigned long size)
+{
+ struct vm_struct *area;
+ unsigned long addr;
+
+ down(&imlist_sem);
+ if (get_free_im_addr(size, &addr)) {
+ printk(KERN_ERR "%s() cannot obtain addr for size 0x%lx\n",
+ __FUNCTION__, size);
+ area = NULL;
+ goto next_im_done;
+ }
+
+ area = __im_get_area(addr, size, IM_REGION_UNUSED);
+ if (area == NULL) {
+ printk(KERN_ERR
+ "%s() cannot obtain area for addr 0x%lx size 0x%lx\n",
+ __FUNCTION__, addr, size);
+ }
+next_im_done:
+ up(&imlist_sem);
+ return area;
+}
+
+struct vm_struct * im_get_area(unsigned long v_addr, unsigned long size,
+ int criteria)
+{
+ struct vm_struct *area;
+
+ down(&imlist_sem);
+ area = __im_get_area(v_addr, size, criteria);
+ up(&imlist_sem);
+ return area;
+}
+
+void im_free(void * addr)
+{
+ struct vm_struct **p, *tmp;
+
+ if (!addr)
+ return;
+ if ((unsigned long) addr & ~PAGE_MASK) {
+ printk(KERN_ERR "Trying to %s bad address (%p)\n", __FUNCTION__, addr);
+ return;
+ }
+ down(&imlist_sem);
+ for (p = &imlist ; (tmp = *p) ; p = &tmp->next) {
+ if (tmp->addr == addr) {
+ *p = tmp->next;
+
+ /* XXX: do we need the lock? */
+ spin_lock(&init_mm.page_table_lock);
+ unmap_vm_area(tmp);
+ spin_unlock(&init_mm.page_table_lock);
+
+ kfree(tmp);
+ up(&imlist_sem);
+ return;
+ }
+ }
+ up(&imlist_sem);
+ printk(KERN_ERR "Trying to %s nonexistent area (%p)\n", __FUNCTION__,
+ addr);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-20 21:39:56 +0100