* Copyright (c) 2000-2003 David McCullough <davidm@snapgear.com>
* Copyright (c) 2000-2001 D Jeff Dionne <jeff@uClinux.org>
* Copyright (c) 2002 Greg Ungerer <gerg@snapgear.com>
+ * Copyright (c) 2007 Paul Mundt <lethal@linux-sh.org>
*/
+#include <linux/module.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/swap.h>
#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
-#include <linux/ptrace.h>
+#include <linux/tracehook.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
#include <linux/mount.h>
unsigned long max_mapnr;
unsigned long num_physpages;
unsigned long askedalloc, realalloc;
-atomic_t vm_committed_space = ATOMIC_INIT(0);
+atomic_long_t vm_committed_space = ATOMIC_LONG_INIT(0);
int sysctl_overcommit_memory = OVERCOMMIT_GUESS; /* heuristic overcommit */
int sysctl_overcommit_ratio = 50; /* default is 50% */
int sysctl_max_map_count = DEFAULT_MAX_MAP_COUNT;
int heap_stack_gap = 0;
EXPORT_SYMBOL(mem_map);
-EXPORT_SYMBOL(__vm_enough_memory);
+EXPORT_SYMBOL(num_physpages);
/* list of shareable VMAs */
struct rb_root nommu_vma_tree = RB_ROOT;
struct vm_operations_struct generic_file_vm_ops = {
};
-EXPORT_SYMBOL(vfree);
-EXPORT_SYMBOL(vmalloc_to_page);
-EXPORT_SYMBOL(vmalloc_32);
-EXPORT_SYMBOL(vmap);
-EXPORT_SYMBOL(vunmap);
-
/*
* Handle all mappings that got truncated by a "truncate()"
* system call.
{
struct page *page;
- if (!objp || !((page = virt_to_page(objp))))
+ /*
+ * If the object we have should not have ksize performed on it,
+ * return size of 0
+ */
+ if (!objp || !virt_addr_valid(objp))
return 0;
+ page = virt_to_head_page(objp);
+
+ /*
+ * If the allocator sets PageSlab, we know the pointer came from
+ * kmalloc().
+ */
if (PageSlab(page))
return ksize(objp);
- BUG_ON(page->index < 0);
- BUG_ON(page->index >= MAX_ORDER);
-
- return (PAGE_SIZE << page->index);
+ /*
+ * The ksize() function is only guaranteed to work for pointers
+ * returned by kmalloc(). So handle arbitrary pointers here.
+ */
+ return PAGE_SIZE << compound_order(page);
}
/*
- * The nommu dodgy version :-)
+ * get a list of pages in an address range belonging to the specified process
+ * and indicate the VMA that covers each page
+ * - this is potentially dodgy as we may end incrementing the page count of a
+ * slab page or a secondary page from a compound page
+ * - don't permit access to VMAs that don't support it, such as I/O mappings
*/
int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, int len, int write, int force,
struct page **pages, struct vm_area_struct **vmas)
{
+ struct vm_area_struct *vma;
+ unsigned long vm_flags;
int i;
- static struct vm_area_struct dummy_vma;
+
+ /* calculate required read or write permissions.
+ * - if 'force' is set, we only require the "MAY" flags.
+ */
+ vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD);
+ vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE);
for (i = 0; i < len; i++) {
+ vma = find_vma(mm, start);
+ if (!vma)
+ goto finish_or_fault;
+
+ /* protect what we can, including chardevs */
+ if (vma->vm_flags & (VM_IO | VM_PFNMAP) ||
+ !(vm_flags & vma->vm_flags))
+ goto finish_or_fault;
+
if (pages) {
pages[i] = virt_to_page(start);
if (pages[i])
page_cache_get(pages[i]);
}
if (vmas)
- vmas[i] = &dummy_vma;
+ vmas[i] = vma;
start += PAGE_SIZE;
}
- return(i);
-}
+ return i;
+
+finish_or_fault:
+ return i ? : -EFAULT;
+}
EXPORT_SYMBOL(get_user_pages);
DEFINE_RWLOCK(vmlist_lock);
struct vm_struct *vmlist;
-void vfree(void *addr)
+void vfree(const void *addr)
{
kfree(addr);
}
+EXPORT_SYMBOL(vfree);
void *__vmalloc(unsigned long size, gfp_t gfp_mask, pgprot_t prot)
{
/*
- * kmalloc doesn't like __GFP_HIGHMEM for some reason
+ * You can't specify __GFP_HIGHMEM with kmalloc() since kmalloc()
+ * returns only a logical address.
*/
return kmalloc(size, (gfp_mask | __GFP_COMP) & ~__GFP_HIGHMEM);
}
+EXPORT_SYMBOL(__vmalloc);
-struct page * vmalloc_to_page(void *addr)
+void *vmalloc_user(unsigned long size)
+{
+ void *ret;
+
+ ret = __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO,
+ PAGE_KERNEL);
+ if (ret) {
+ struct vm_area_struct *vma;
+
+ down_write(¤t->mm->mmap_sem);
+ vma = find_vma(current->mm, (unsigned long)ret);
+ if (vma)
+ vma->vm_flags |= VM_USERMAP;
+ up_write(¤t->mm->mmap_sem);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(vmalloc_user);
+
+struct page *vmalloc_to_page(const void *addr)
{
return virt_to_page(addr);
}
+EXPORT_SYMBOL(vmalloc_to_page);
-unsigned long vmalloc_to_pfn(void *addr)
+unsigned long vmalloc_to_pfn(const void *addr)
{
return page_to_pfn(virt_to_page(addr));
}
-
+EXPORT_SYMBOL(vmalloc_to_pfn);
long vread(char *buf, char *addr, unsigned long count)
{
* Allocate enough pages to cover @size from the page level
* allocator and map them into continguos kernel virtual space.
*
- * For tight cotrol over page level allocator and protection flags
+ * For tight control over page level allocator and protection flags
* use __vmalloc() instead.
*/
void *vmalloc(unsigned long size)
}
EXPORT_SYMBOL(vmalloc_node);
-/*
- * vmalloc_32 - allocate virtually continguos memory (32bit addressable)
+#ifndef PAGE_KERNEL_EXEC
+# define PAGE_KERNEL_EXEC PAGE_KERNEL
+#endif
+
+/**
+ * vmalloc_exec - allocate virtually contiguous, executable memory
+ * @size: allocation size
+ *
+ * Kernel-internal function to allocate enough pages to cover @size
+ * the page level allocator and map them into contiguous and
+ * executable kernel virtual space.
*
+ * For tight control over page level allocator and protection flags
+ * use __vmalloc() instead.
+ */
+
+void *vmalloc_exec(unsigned long size)
+{
+ return __vmalloc(size, GFP_KERNEL | __GFP_HIGHMEM, PAGE_KERNEL_EXEC);
+}
+
+/**
+ * vmalloc_32 - allocate virtually contiguous memory (32bit addressable)
* @size: allocation size
*
* Allocate enough 32bit PA addressable pages to cover @size from the
{
return __vmalloc(size, GFP_KERNEL, PAGE_KERNEL);
}
+EXPORT_SYMBOL(vmalloc_32);
+
+/**
+ * vmalloc_32_user - allocate zeroed virtually contiguous 32bit memory
+ * @size: allocation size
+ *
+ * The resulting memory area is 32bit addressable and zeroed so it can be
+ * mapped to userspace without leaking data.
+ *
+ * VM_USERMAP is set on the corresponding VMA so that subsequent calls to
+ * remap_vmalloc_range() are permissible.
+ */
+void *vmalloc_32_user(unsigned long size)
+{
+ /*
+ * We'll have to sort out the ZONE_DMA bits for 64-bit,
+ * but for now this can simply use vmalloc_user() directly.
+ */
+ return vmalloc_user(size);
+}
+EXPORT_SYMBOL(vmalloc_32_user);
void *vmap(struct page **pages, unsigned int count, unsigned long flags, pgprot_t prot)
{
BUG();
return NULL;
}
+EXPORT_SYMBOL(vmap);
-void vunmap(void *addr)
+void vunmap(const void *addr)
{
BUG();
}
+EXPORT_SYMBOL(vunmap);
+
+/*
+ * Implement a stub for vmalloc_sync_all() if the architecture chose not to
+ * have one.
+ */
+void __attribute__((weak)) vmalloc_sync_all(void)
+{
+}
+
+int vm_insert_page(struct vm_area_struct *vma, unsigned long addr,
+ struct page *page)
+{
+ return -EINVAL;
+}
+EXPORT_SYMBOL(vm_insert_page);
/*
* sys_brk() for the most part doesn't need the global kernel
}
#endif /* DEBUG */
+/*
+ * add a VMA into a process's mm_struct in the appropriate place in the list
+ * - should be called with mm->mmap_sem held writelocked
+ */
+static void add_vma_to_mm(struct mm_struct *mm, struct vm_list_struct *vml)
+{
+ struct vm_list_struct **ppv;
+
+ for (ppv = ¤t->mm->context.vmlist; *ppv; ppv = &(*ppv)->next)
+ if ((*ppv)->vma->vm_start > vml->vma->vm_start)
+ break;
+
+ vml->next = *ppv;
+ *ppv = vml;
+}
+
+/*
+ * look up the first VMA in which addr resides, NULL if none
+ * - should be called with mm->mmap_sem at least held readlocked
+ */
+struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
+{
+ struct vm_list_struct *loop, *vml;
+
+ /* search the vm_start ordered list */
+ vml = NULL;
+ for (loop = mm->context.vmlist; loop; loop = loop->next) {
+ if (loop->vma->vm_start > addr)
+ break;
+ vml = loop;
+ }
+
+ if (vml && vml->vma->vm_end > addr)
+ return vml->vma;
+
+ return NULL;
+}
+EXPORT_SYMBOL(find_vma);
+
+/*
+ * find a VMA
+ * - we don't extend stack VMAs under NOMMU conditions
+ */
+struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
+{
+ return find_vma(mm, addr);
+}
+
+int expand_stack(struct vm_area_struct *vma, unsigned long address)
+{
+ return -ENOMEM;
+}
+
+/*
+ * look up the first VMA exactly that exactly matches addr
+ * - should be called with mm->mmap_sem at least held readlocked
+ */
+static inline struct vm_area_struct *find_vma_exact(struct mm_struct *mm,
+ unsigned long addr)
+{
+ struct vm_list_struct *vml;
+
+ /* search the vm_start ordered list */
+ for (vml = mm->context.vmlist; vml; vml = vml->next) {
+ if (vml->vma->vm_start == addr)
+ return vml->vma;
+ if (vml->vma->vm_start > addr)
+ break;
+ }
+
+ return NULL;
+}
+
+/*
+ * find a VMA in the global tree
+ */
static inline struct vm_area_struct *find_nommu_vma(unsigned long start)
{
struct vm_area_struct *vma;
return NULL;
}
+/*
+ * add a VMA in the global tree
+ */
static void add_nommu_vma(struct vm_area_struct *vma)
{
struct vm_area_struct *pvma;
rb_insert_color(&vma->vm_rb, &nommu_vma_tree);
}
+/*
+ * delete a VMA from the global list
+ */
static void delete_nommu_vma(struct vm_area_struct *vma)
{
struct address_space *mapping;
(flags & MAP_TYPE) != MAP_SHARED)
return -EINVAL;
- if (PAGE_ALIGN(len) == 0)
- return addr;
-
- if (len > TASK_SIZE)
+ if (!len)
return -EINVAL;
+ /* Careful about overflows.. */
+ len = PAGE_ALIGN(len);
+ if (!len || len > TASK_SIZE)
+ return -ENOMEM;
+
/* offset overflow? */
if ((pgoff + (len >> PAGE_SHIFT)) < pgoff)
- return -EINVAL;
+ return -EOVERFLOW;
if (file) {
/* validate file mapping requests */
*/
mapping = file->f_mapping;
if (!mapping)
- mapping = file->f_dentry->d_inode->i_mapping;
+ mapping = file->f_path.dentry->d_inode->i_mapping;
capabilities = 0;
if (mapping && mapping->backing_dev_info)
if (!capabilities) {
/* no explicit capabilities set, so assume some
* defaults */
- switch (file->f_dentry->d_inode->i_mode & S_IFMT) {
+ switch (file->f_path.dentry->d_inode->i_mode & S_IFMT) {
case S_IFREG:
case S_IFBLK:
capabilities = BDI_CAP_MAP_COPY;
!(file->f_mode & FMODE_WRITE))
return -EACCES;
- if (IS_APPEND(file->f_dentry->d_inode) &&
+ if (IS_APPEND(file->f_path.dentry->d_inode) &&
(file->f_mode & FMODE_WRITE))
return -EACCES;
- if (locks_verify_locked(file->f_dentry->d_inode))
+ if (locks_verify_locked(file->f_path.dentry->d_inode))
return -EAGAIN;
if (!(capabilities & BDI_CAP_MAP_DIRECT))
/* handle executable mappings and implied executable
* mappings */
- if (file->f_vfsmnt->mnt_flags & MNT_NOEXEC) {
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) {
if (prot & PROT_EXEC)
return -EPERM;
}
}
/* allow the security API to have its say */
- ret = security_file_mmap(file, reqprot, prot, flags);
+ ret = security_file_mmap(file, reqprot, prot, flags, addr, 0);
if (ret < 0)
return ret;
* it's being traced - otherwise breakpoints set in it may interfere
* with another untraced process
*/
- if ((flags & MAP_PRIVATE) && (current->ptrace & PT_PTRACED))
+ if ((flags & MAP_PRIVATE) && tracehook_expect_breakpoints(current))
vm_flags &= ~VM_MAYSHARE;
return vm_flags;
void *result;
int ret;
+ if (!(flags & MAP_FIXED))
+ addr = round_hint_to_min(addr);
+
/* decide whether we should attempt the mapping, and if so what sort of
* mapping */
ret = validate_mmap_request(file, addr, len, prot, flags, pgoff,
vm_flags = determine_vm_flags(file, prot, flags, capabilities);
/* we're going to need to record the mapping if it works */
- vml = kmalloc(sizeof(struct vm_list_struct), GFP_KERNEL);
+ vml = kzalloc(sizeof(struct vm_list_struct), GFP_KERNEL);
if (!vml)
goto error_getting_vml;
- memset(vml, 0, sizeof(*vml));
down_write(&nommu_vma_sem);
unsigned long pglen = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
unsigned long vmpglen;
+ /* suppress VMA sharing for shared regions */
+ if (vm_flags & VM_SHARED &&
+ capabilities & BDI_CAP_MAP_DIRECT)
+ goto dont_share_VMAs;
+
for (rb = rb_first(&nommu_vma_tree); rb; rb = rb_next(rb)) {
vma = rb_entry(rb, struct vm_area_struct, vm_rb);
continue;
/* search for overlapping mappings on the same file */
- if (vma->vm_file->f_dentry->d_inode != file->f_dentry->d_inode)
+ if (vma->vm_file->f_path.dentry->d_inode != file->f_path.dentry->d_inode)
continue;
if (vma->vm_pgoff >= pgoff + pglen)
goto shared;
}
+ dont_share_VMAs:
vma = NULL;
/* obtain the address at which to make a shared mapping
}
/* we're going to need a VMA struct as well */
- vma = kmalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
+ vma = kzalloc(sizeof(struct vm_area_struct), GFP_KERNEL);
if (!vma)
goto error_getting_vma;
- memset(vma, 0, sizeof(*vma));
INIT_LIST_HEAD(&vma->anon_vma_node);
atomic_set(&vma->vm_usage, 1);
- if (file)
+ if (file) {
get_file(file);
+ if (vm_flags & VM_EXECUTABLE) {
+ added_exe_file_vma(current->mm);
+ vma->vm_mm = current->mm;
+ }
+ }
vma->vm_file = file;
vma->vm_flags = vm_flags;
vma->vm_start = addr;
realalloc += kobjsize(vml);
askedalloc += sizeof(*vml);
- vml->next = current->mm->context.vmlist;
- current->mm->context.vmlist = vml;
+ add_vma_to_mm(current->mm, vml);
up_write(&nommu_vma_sem);
up_write(&nommu_vma_sem);
kfree(vml);
if (vma) {
- fput(vma->vm_file);
+ if (vma->vm_file) {
+ fput(vma->vm_file);
+ if (vma->vm_flags & VM_EXECUTABLE)
+ removed_exe_file_vma(vma->vm_mm);
+ }
kfree(vma);
}
return ret;
show_free_areas();
return -ENOMEM;
}
+EXPORT_SYMBOL(do_mmap_pgoff);
/*
* handle mapping disposal for uClinux
*/
-static void put_vma(struct vm_area_struct *vma)
+static void put_vma(struct mm_struct *mm, struct vm_area_struct *vma)
{
if (vma) {
down_write(&nommu_vma_sem);
realalloc -= kobjsize(vma);
askedalloc -= sizeof(*vma);
- if (vma->vm_file)
+ if (vma->vm_file) {
fput(vma->vm_file);
+ if (vma->vm_flags & VM_EXECUTABLE)
+ removed_exe_file_vma(mm);
+ }
kfree(vma);
}
}
}
+/*
+ * release a mapping
+ * - under NOMMU conditions the parameters must match exactly to the mapping to
+ * be removed
+ */
int do_munmap(struct mm_struct *mm, unsigned long addr, size_t len)
{
struct vm_list_struct *vml, **parent;
printk("do_munmap:\n");
#endif
- for (parent = &mm->context.vmlist; *parent; parent = &(*parent)->next)
+ for (parent = &mm->context.vmlist; *parent; parent = &(*parent)->next) {
+ if ((*parent)->vma->vm_start > addr)
+ break;
if ((*parent)->vma->vm_start == addr &&
((len == 0) || ((*parent)->vma->vm_end == end)))
goto found;
+ }
printk("munmap of non-mmaped memory by process %d (%s): %p\n",
current->pid, current->comm, (void *) addr);
found:
vml = *parent;
- put_vma(vml->vma);
+ put_vma(mm, vml->vma);
*parent = vml->next;
realalloc -= kobjsize(vml);
return 0;
}
+EXPORT_SYMBOL(do_munmap);
+
+asmlinkage long sys_munmap(unsigned long addr, size_t len)
+{
+ int ret;
+ struct mm_struct *mm = current->mm;
+
+ down_write(&mm->mmap_sem);
+ ret = do_munmap(mm, addr, len);
+ up_write(&mm->mmap_sem);
+ return ret;
+}
-/* Release all mmaps. */
+/*
+ * Release all mappings
+ */
void exit_mmap(struct mm_struct * mm)
{
struct vm_list_struct *tmp;
while ((tmp = mm->context.vmlist)) {
mm->context.vmlist = tmp->next;
- put_vma(tmp->vma);
+ put_vma(mm, tmp->vma);
realalloc -= kobjsize(tmp);
askedalloc -= sizeof(*tmp);
}
}
-asmlinkage long sys_munmap(unsigned long addr, size_t len)
-{
- int ret;
- struct mm_struct *mm = current->mm;
-
- down_write(&mm->mmap_sem);
- ret = do_munmap(mm, addr, len);
- up_write(&mm->mmap_sem);
- return ret;
-}
-
unsigned long do_brk(unsigned long addr, unsigned long len)
{
return -ENOMEM;
}
/*
- * Expand (or shrink) an existing mapping, potentially moving it at the
- * same time (controlled by the MREMAP_MAYMOVE flag and available VM space)
+ * expand (or shrink) an existing mapping, potentially moving it at the same
+ * time (controlled by the MREMAP_MAYMOVE flag and available VM space)
*
- * MREMAP_FIXED option added 5-Dec-1999 by Benjamin LaHaise
- * This option implies MREMAP_MAYMOVE.
+ * under NOMMU conditions, we only permit changing a mapping's size, and only
+ * as long as it stays within the hole allocated by the kmalloc() call in
+ * do_mmap_pgoff() and the block is not shareable
*
- * on uClinux, we only permit changing a mapping's size, and only as long as it stays within the
- * hole allocated by the kmalloc() call in do_mmap_pgoff() and the block is not shareable
+ * MREMAP_FIXED is not supported under NOMMU conditions
*/
unsigned long do_mremap(unsigned long addr,
unsigned long old_len, unsigned long new_len,
unsigned long flags, unsigned long new_addr)
{
- struct vm_list_struct *vml = NULL;
+ struct vm_area_struct *vma;
/* insanity checks first */
if (new_len == 0)
if (flags & MREMAP_FIXED && new_addr != addr)
return (unsigned long) -EINVAL;
- for (vml = current->mm->context.vmlist; vml; vml = vml->next)
- if (vml->vma->vm_start == addr)
- goto found;
-
- return (unsigned long) -EINVAL;
+ vma = find_vma_exact(current->mm, addr);
+ if (!vma)
+ return (unsigned long) -EINVAL;
- found:
- if (vml->vma->vm_end != vml->vma->vm_start + old_len)
+ if (vma->vm_end != vma->vm_start + old_len)
return (unsigned long) -EFAULT;
- if (vml->vma->vm_flags & VM_MAYSHARE)
+ if (vma->vm_flags & VM_MAYSHARE)
return (unsigned long) -EPERM;
if (new_len > kobjsize((void *) addr))
return (unsigned long) -ENOMEM;
/* all checks complete - do it */
- vml->vma->vm_end = vml->vma->vm_start + new_len;
+ vma->vm_end = vma->vm_start + new_len;
askedalloc -= old_len;
askedalloc += new_len;
- return vml->vma->vm_start;
+ return vma->vm_start;
}
+EXPORT_SYMBOL(do_mremap);
-/*
- * Look up the first VMA which satisfies addr < vm_end, NULL if none
- */
-struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr)
+asmlinkage unsigned long sys_mremap(unsigned long addr,
+ unsigned long old_len, unsigned long new_len,
+ unsigned long flags, unsigned long new_addr)
{
- struct vm_list_struct *vml;
-
- for (vml = mm->context.vmlist; vml; vml = vml->next)
- if (addr >= vml->vma->vm_start && addr < vml->vma->vm_end)
- return vml->vma;
+ unsigned long ret;
- return NULL;
+ down_write(¤t->mm->mmap_sem);
+ ret = do_mremap(addr, old_len, new_len, flags, new_addr);
+ up_write(¤t->mm->mmap_sem);
+ return ret;
}
-EXPORT_SYMBOL(find_vma);
-
struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
unsigned int foll_flags)
{
return NULL;
}
-struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr)
-{
- return NULL;
-}
-
int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
unsigned long to, unsigned long size, pgprot_t prot)
{
vma->vm_start = vma->vm_pgoff << PAGE_SHIFT;
return 0;
}
+EXPORT_SYMBOL(remap_pfn_range);
+
+int remap_vmalloc_range(struct vm_area_struct *vma, void *addr,
+ unsigned long pgoff)
+{
+ unsigned int size = vma->vm_end - vma->vm_start;
+
+ if (!(vma->vm_flags & VM_USERMAP))
+ return -EINVAL;
+
+ vma->vm_start = (unsigned long)(addr + (pgoff << PAGE_SHIFT));
+ vma->vm_end = vma->vm_start + size;
+
+ return 0;
+}
+EXPORT_SYMBOL(remap_vmalloc_range);
void swap_unplug_io_fn(struct backing_dev_info *bdi, struct page *page)
{
int even_cows)
{
}
+EXPORT_SYMBOL(unmap_mapping_range);
+
+/*
+ * ask for an unmapped area at which to create a mapping on a file
+ */
+unsigned long get_unmapped_area(struct file *file, unsigned long addr,
+ unsigned long len, unsigned long pgoff,
+ unsigned long flags)
+{
+ unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
+ unsigned long, unsigned long);
+
+ get_area = current->mm->get_unmapped_area;
+ if (file && file->f_op && file->f_op->get_unmapped_area)
+ get_area = file->f_op->get_unmapped_area;
+
+ if (!get_area)
+ return -ENOSYS;
+
+ return get_area(file, addr, len, pgoff, flags);
+}
+EXPORT_SYMBOL(get_unmapped_area);
/*
* Check that a process has enough memory to allocate a new virtual
* Note this is a helper function intended to be used by LSMs which
* wish to use this logic.
*/
-int __vm_enough_memory(long pages, int cap_sys_admin)
+int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
{
unsigned long free, allowed;
if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
unsigned long n;
- free = get_page_cache_size();
+ free = global_page_state(NR_FILE_PAGES);
free += nr_swap_pages;
/*
* which are reclaimable, under pressure. The dentry
* cache and most inode caches should fall into this
*/
- free += atomic_read(&slab_reclaim_pages);
+ free += global_page_state(NR_SLAB_RECLAIMABLE);
/*
* Leave the last 3% for root
* only call if we're about to fail.
*/
n = nr_free_pages();
+
+ /*
+ * Leave reserved pages. The pages are not for anonymous pages.
+ */
+ if (n <= totalreserve_pages)
+ goto error;
+ else
+ n -= totalreserve_pages;
+
+ /*
+ * Leave the last 3% for root
+ */
if (!cap_sys_admin)
n -= n / 32;
free += n;
if (free > pages)
return 0;
- vm_unacct_memory(pages);
- return -ENOMEM;
+
+ goto error;
}
allowed = totalram_pages * sysctl_overcommit_ratio / 100;
* cast `allowed' as a signed long because vm_committed_space
* sometimes has a negative value
*/
- if (atomic_read(&vm_committed_space) < (long)allowed)
+ if (atomic_long_read(&vm_committed_space) < (long)allowed)
return 0;
-
+error:
vm_unacct_memory(pages);
return -ENOMEM;
return 0;
}
-struct page *filemap_nopage(struct vm_area_struct *area,
- unsigned long address, int *type)
+int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
BUG();
- return NULL;
+ return 0;
+}
+EXPORT_SYMBOL(filemap_fault);
+
+/*
+ * Access another process' address space.
+ * - source/target buffer must be kernel space
+ */
+int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
+{
+ struct vm_area_struct *vma;
+ struct mm_struct *mm;
+
+ if (addr + len < addr)
+ return 0;
+
+ mm = get_task_mm(tsk);
+ if (!mm)
+ return 0;
+
+ down_read(&mm->mmap_sem);
+
+ /* the access must start within one of the target process's mappings */
+ vma = find_vma(mm, addr);
+ if (vma) {
+ /* don't overrun this mapping */
+ if (addr + len >= vma->vm_end)
+ len = vma->vm_end - addr;
+
+ /* only read or write mappings where it is permitted */
+ if (write && vma->vm_flags & VM_MAYWRITE)
+ len -= copy_to_user((void *) addr, buf, len);
+ else if (!write && vma->vm_flags & VM_MAYREAD)
+ len -= copy_from_user(buf, (void *) addr, len);
+ else
+ len = 0;
+ } else {
+ len = 0;
+ }
+
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+ return len;
}