1 files changed, 312 insertions, 0 deletions

diff --git a/arch/powerpc/mm/imalloc.c b/arch/powerpc/mm/imalloc.c
new file mode 100644
index 000000000000..f4ca29cf5364
--- /dev/null
+++ b/arch/powerpc/mm/imalloc.c
@@ -0,0 +1,312 @@
+/*
+ * 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;
+                        unmap_vm_area(tmp);
+                        kfree(tmp);
+                        up(&imlist_sem);
+                        return;
+                }
+        }
+        up(&imlist_sem);
+        printk(KERN_ERR "Trying to %s nonexistent area (%p)\n", __FUNCTION__,
+                        addr);
+}