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;
}
/*
- * 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);
* 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)
}
/*
+ * Implement a stub for vmalloc_sync_all() if the architecture chose not to
+ * have one.
+ */
+void __attribute__((weak)) vmalloc_sync_all(void)
+{
+}
+
+/*
* sys_brk() for the most part doesn't need the global kernel
* lock, except when an application is doing something nasty
* like trying to un-brk an area that has already been mapped
}
#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;
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)
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);
kfree(vma);
}
return ret;
}
}
+/*
+ * 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);
return 0;
}
-/* Release all mmaps. */
+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 mappings
+ */
void exit_mmap(struct mm_struct * mm)
{
struct vm_list_struct *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;
}
-/*
- * 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;
+ unsigned long ret;
- for (vml = mm->context.vmlist; vml; vml = vml->next)
- if (addr >= vml->vma->vm_start && addr < vml->vma->vm_end)
- return vml->vma;
-
- 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)
{
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
* mapping. 0 means there is enough memory for the allocation to
* succeed and -ENOMEM implies there is not.
*/
int access_process_vm(struct task_struct *tsk, unsigned long addr, void *buf, int len, int write)
{
- struct vm_list_struct *vml;
struct vm_area_struct *vma;
struct mm_struct *mm;
down_read(&mm->mmap_sem);
/* the access must start within one of the target process's mappings */
- for (vml = mm->context.vmlist; vml; vml = vml->next)
- if (addr >= vml->vma->vm_start && addr < vml->vma->vm_end)
- break;
-
- if (vml) {
- vma = vml->vma;
-
+ 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_WRITE)
+ if (write && vma->vm_flags & VM_MAYWRITE)
len -= copy_to_user((void *) addr, buf, len);
- else if (!write && vma->vm_flags & VM_READ)
+ else if (!write && vma->vm_flags & VM_MAYREAD)
len -= copy_from_user(buf, (void *) addr, len);
else
len = 0;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff