Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / mm / nommu.c

diff --git a/mm/nommu.c b/mm/nommu.c
index 3650195..cbbc137 100644 (file)
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -221,7 +221,7 @@ long vwrite(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)
@@ -497,15 +497,17 @@ static int validate_mmap_request(struct file *file,
            (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 */
@@ -521,7 +523,7 @@ static int validate_mmap_request(struct file *file,
                 */
                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)
@@ -530,7 +532,7 @@ static int validate_mmap_request(struct file *file,
                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;
@@ -561,11 +563,11 @@ static int validate_mmap_request(struct file *file,
                            !(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))
@@ -596,7 +598,7 @@ static int validate_mmap_request(struct file *file,
 
                /* 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;
                }
@@ -806,10 +808,9 @@ unsigned long do_mmap_pgoff(struct file *file,
        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);
 
@@ -825,6 +826,11 @@ unsigned long do_mmap_pgoff(struct file *file,
                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);
 
@@ -832,7 +838,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                                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)
@@ -858,6 +864,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                        goto shared;
                }
 
+       dont_share_VMAs:
                vma = NULL;
 
                /* obtain the address at which to make a shared mapping
@@ -885,11 +892,10 @@ unsigned long do_mmap_pgoff(struct file *file,
        }
 
        /* 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)
@@ -1192,6 +1198,28 @@ void unmap_mapping_range(struct address_space *mapping,
 }
 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