+++ /dev/null
-/*
- * linux/mm/vmalloc.c
- *
- * Copyright (C) 1993 Linus Torvalds
- * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
- * SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
- */
-
-#include <linux/config.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include <linux/spinlock.h>
-#include <linux/highmem.h>
-#include <linux/smp_lock.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgalloc.h>
-
-rwlock_t vmlist_lock = RW_LOCK_UNLOCKED;
-struct vm_struct * vmlist;
-
-static inline void free_area_pte(pmd_t * pmd, unsigned long address, unsigned long size)
-{
- pte_t * pte;
- unsigned long end;
-
- if (pmd_none(*pmd))
- return;
- if (pmd_bad(*pmd)) {
- pmd_ERROR(*pmd);
- pmd_clear(pmd);
- return;
- }
- pte = pte_offset(pmd, address);
- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
- do {
- pte_t page;
- page = ptep_get_and_clear(pte);
- address += PAGE_SIZE;
- pte++;
- if (pte_none(page))
- continue;
- if (pte_present(page)) {
- struct page *ptpage = pte_page(page);
-#if defined(CONFIG_XEN_PRIVILEGED_GUEST)
- if (pte_io(page))
- continue;
-#endif
- if (VALID_PAGE(ptpage) && (!PageReserved(ptpage)))
- __free_page(ptpage);
- continue;
- }
- printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
- } while (address < end);
-}
-
-static inline void free_area_pmd(pgd_t * dir, unsigned long address, unsigned long size)
-{
- pmd_t * pmd;
- unsigned long end;
-
- if (pgd_none(*dir))
- return;
- if (pgd_bad(*dir)) {
- pgd_ERROR(*dir);
- pgd_clear(dir);
- return;
- }
- pmd = pmd_offset(dir, address);
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
- do {
- free_area_pte(pmd, address, end - address);
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address < end);
-}
-
-void vmfree_area_pages(unsigned long address, unsigned long size)
-{
- pgd_t * dir;
- unsigned long end = address + size;
-
- dir = pgd_offset_k(address);
- flush_cache_all();
- do {
- free_area_pmd(dir, address, end - address);
- address = (address + PGDIR_SIZE) & PGDIR_MASK;
- dir++;
- } while (address && (address < end));
- flush_tlb_all();
-}
-
-static inline int alloc_area_pte (pte_t * pte, unsigned long address,
- unsigned long size, int gfp_mask,
- pgprot_t prot, struct page ***pages)
-{
- unsigned long end;
-
- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
- do {
- struct page * page;
-
- if (!pages) {
- spin_unlock(&init_mm.page_table_lock);
- page = alloc_page(gfp_mask);
- spin_lock(&init_mm.page_table_lock);
- } else {
- page = (**pages);
- (*pages)++;
-
- /* Add a reference to the page so we can free later */
- if (page)
- atomic_inc(&page->count);
-
- }
- if (!pte_none(*pte))
- printk(KERN_ERR "alloc_area_pte: page already exists\n");
- if (!page)
- return -ENOMEM;
- set_pte(pte, mk_pte(page, prot));
- address += PAGE_SIZE;
- pte++;
- } while (address < end);
- return 0;
-}
-
-static inline int alloc_area_pmd(pmd_t * pmd, unsigned long address,
- unsigned long size, int gfp_mask,
- pgprot_t prot, struct page ***pages)
-{
- unsigned long end;
-
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
- do {
- pte_t * pte = pte_alloc(&init_mm, pmd, address);
- if (!pte)
- return -ENOMEM;
- if (alloc_area_pte(pte, address, end - address,
- gfp_mask, prot, pages))
- return -ENOMEM;
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address < end);
- return 0;
-}
-
-static inline int __vmalloc_area_pages (unsigned long address,
- unsigned long size,
- int gfp_mask,
- pgprot_t prot,
- struct page ***pages)
-{
- pgd_t * dir;
- unsigned long start = address;
- unsigned long end = address + size;
-
- dir = pgd_offset_k(address);
- spin_lock(&init_mm.page_table_lock);
- do {
- pmd_t *pmd;
-
- pmd = pmd_alloc(&init_mm, dir, address);
- if (!pmd)
- goto err;
-
- if (alloc_area_pmd(pmd, address, end - address, gfp_mask, prot, pages))
- goto err; // The kernel NEVER reclaims pmds, so no need to undo pmd_alloc() here
-
- address = (address + PGDIR_SIZE) & PGDIR_MASK;
- dir++;
- } while (address && (address < end));
- spin_unlock(&init_mm.page_table_lock);
- flush_cache_all();
- return 0;
-err:
- spin_unlock(&init_mm.page_table_lock);
- flush_cache_all();
- if (address > start)
- vmfree_area_pages(start, address - start);
- return -ENOMEM;
-}
-
-int vmalloc_area_pages(unsigned long address, unsigned long size,
- int gfp_mask, pgprot_t prot)
-{
- return __vmalloc_area_pages(address, size, gfp_mask, prot, NULL);
-}
-
-struct vm_struct * get_vm_area(unsigned long size, unsigned long flags)
-{
- unsigned long addr, next;
- struct vm_struct **p, *tmp, *area;
-
- area = (struct vm_struct *) kmalloc(sizeof(*area), GFP_KERNEL);
- if (!area)
- return NULL;
-
- size += PAGE_SIZE;
- if (!size) {
- kfree (area);
- return NULL;
- }
-
- addr = VMALLOC_START;
- write_lock(&vmlist_lock);
- for (p = &vmlist; (tmp = *p) ; p = &tmp->next) {
- if ((size + addr) < addr)
- goto out;
- if (size + addr <= (unsigned long) tmp->addr)
- break;
- next = tmp->size + (unsigned long) tmp->addr;
- if (next > addr)
- addr = next;
- if (addr > VMALLOC_END-size)
- goto out;
- }
- area->flags = flags;
- area->addr = (void *)addr;
- area->size = size;
- area->next = *p;
- *p = area;
- write_unlock(&vmlist_lock);
- return area;
-
-out:
- write_unlock(&vmlist_lock);
- kfree(area);
- return NULL;
-}
-
-void __vfree(void * addr, int free_area_pages)
-{
- struct vm_struct **p, *tmp;
-
- if (!addr)
- return;
- if ((PAGE_SIZE-1) & (unsigned long) addr) {
- printk(KERN_ERR "Trying to vfree() bad address (%p)\n", addr);
- return;
- }
- write_lock(&vmlist_lock);
- for (p = &vmlist ; (tmp = *p) ; p = &tmp->next) {
- if (tmp->addr == addr) {
- *p = tmp->next;
- if (free_area_pages)
- vmfree_area_pages(VMALLOC_VMADDR(tmp->addr), tmp->size);
- write_unlock(&vmlist_lock);
- kfree(tmp);
- return;
- }
- }
- write_unlock(&vmlist_lock);
- printk(KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n", addr);
-}
-
-void vfree(void * addr)
-{
- __vfree(addr,1);
-}
-
-void * __vmalloc (unsigned long size, int gfp_mask, pgprot_t prot)
-{
- void * addr;
- struct vm_struct *area;
-
- size = PAGE_ALIGN(size);
- if (!size || (size >> PAGE_SHIFT) > num_physpages)
- return NULL;
- area = get_vm_area(size, VM_ALLOC);
- if (!area)
- return NULL;
- addr = area->addr;
- if (__vmalloc_area_pages(VMALLOC_VMADDR(addr), size, gfp_mask,
- prot, NULL)) {
- __vfree(addr, 0);
- return NULL;
- }
- return addr;
-}
-
-void * vmap(struct page **pages, int count,
- unsigned long flags, pgprot_t prot)
-{
- void * addr;
- struct vm_struct *area;
- unsigned long size = count << PAGE_SHIFT;
-
- if (!size || size > (max_mapnr << PAGE_SHIFT))
- return NULL;
- area = get_vm_area(size, flags);
- if (!area) {
- return NULL;
- }
- addr = area->addr;
- if (__vmalloc_area_pages(VMALLOC_VMADDR(addr), size, 0,
- prot, &pages)) {
- __vfree(addr, 0);
- return NULL;
- }
- return addr;
-}
-
-long vread(char *buf, char *addr, unsigned long count)
-{
- struct vm_struct *tmp;
- char *vaddr, *buf_start = buf;
- unsigned long n;
-
- /* Don't allow overflow */
- if ((unsigned long) addr + count < count)
- count = -(unsigned long) addr;
-
- read_lock(&vmlist_lock);
- for (tmp = vmlist; tmp; tmp = tmp->next) {
- vaddr = (char *) tmp->addr;
- if (addr >= vaddr + tmp->size - PAGE_SIZE)
- continue;
- while (addr < vaddr) {
- if (count == 0)
- goto finished;
- *buf = '\0';
- buf++;
- addr++;
- count--;
- }
- n = vaddr + tmp->size - PAGE_SIZE - addr;
- do {
- if (count == 0)
- goto finished;
- *buf = *addr;
- buf++;
- addr++;
- count--;
- } while (--n > 0);
- }
-finished:
- read_unlock(&vmlist_lock);
- return buf - buf_start;
-}
-
-long vwrite(char *buf, char *addr, unsigned long count)
-{
- struct vm_struct *tmp;
- char *vaddr, *buf_start = buf;
- unsigned long n;
-
- /* Don't allow overflow */
- if ((unsigned long) addr + count < count)
- count = -(unsigned long) addr;
-
- read_lock(&vmlist_lock);
- for (tmp = vmlist; tmp; tmp = tmp->next) {
- vaddr = (char *) tmp->addr;
- if (addr >= vaddr + tmp->size - PAGE_SIZE)
- continue;
- while (addr < vaddr) {
- if (count == 0)
- goto finished;
- buf++;
- addr++;
- count--;
- }
- n = vaddr + tmp->size - PAGE_SIZE - addr;
- do {
- if (count == 0)
- goto finished;
- *addr = *buf;
- buf++;
- addr++;
- count--;
- } while (--n > 0);
- }
-finished:
- read_unlock(&vmlist_lock);
- return buf - buf_start;
-}
projects / xen.git / commitdiff