file ->get_unmapped_area() shouldn't duplicate work of get_unmapped_area()
Al Viro [Mon, 30 Nov 2009 13:38:43 +0000 (08:38 -0500)]
... we should call mm ->get_unmapped_area() instead and let our caller
do the final checks.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/sparc/kernel/sys_sparc_64.c
ipc/shm.c

index ddda12f..d498b32 100644 (file)
@@ -317,10 +317,14 @@ bottomup:
 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
 {
        unsigned long align_goal, addr = -ENOMEM;
+       unsigned long (*get_area)(struct file *, unsigned long,
+                                 unsigned long, unsigned long, unsigned long);
+
+       get_area = current->mm->get_unmapped_area;
 
        if (flags & MAP_FIXED) {
                /* Ok, don't mess with it. */
-               return get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+               return get_area(NULL, orig_addr, len, pgoff, flags);
        }
        flags &= ~MAP_SHARED;
 
@@ -333,7 +337,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
                align_goal = (64UL * 1024);
 
        do {
-               addr = get_unmapped_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
+               addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
                if (!(addr & ~PAGE_MASK)) {
                        addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
                        break;
@@ -351,7 +355,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
         * be obtained.
         */
        if (addr & ~PAGE_MASK)
-               addr = get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+               addr = get_area(NULL, orig_addr, len, pgoff, flags);
 
        return addr;
 }
index 464694e..11bec62 100644 (file)
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -290,28 +290,28 @@ static unsigned long shm_get_unmapped_area(struct file *file,
        unsigned long flags)
 {
        struct shm_file_data *sfd = shm_file_data(file);
-       return get_unmapped_area(sfd->file, addr, len, pgoff, flags);
-}
-
-int is_file_shm_hugepages(struct file *file)
-{
-       int ret = 0;
-
-       if (file->f_op == &shm_file_operations) {
-               struct shm_file_data *sfd;
-               sfd = shm_file_data(file);
-               ret = is_file_hugepages(sfd->file);
-       }
-       return ret;
+       return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
+                                               pgoff, flags);
 }
 
 static const struct file_operations shm_file_operations = {
        .mmap           = shm_mmap,
        .fsync          = shm_fsync,
        .release        = shm_release,
+};
+
+static const struct file_operations shm_file_operations_huge = {
+       .mmap           = shm_mmap,
+       .fsync          = shm_fsync,
+       .release        = shm_release,
        .get_unmapped_area      = shm_get_unmapped_area,
 };
 
+int is_file_shm_hugepages(struct file *file)
+{
+       return file->f_op == &shm_file_operations_huge;
+}
+
 static const struct vm_operations_struct shm_vm_ops = {
        .open   = shm_open,     /* callback for a new vm-area open */
        .close  = shm_close,    /* callback for when the vm-area is released */
@@ -889,7 +889,10 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
        if (!sfd)
                goto out_put_dentry;
 
-       file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations);
+       file = alloc_file(path.mnt, path.dentry, f_mode,
+                       is_file_hugepages(shp->shm_file) ?
+                               &shm_file_operations_huge :
+                               &shm_file_operations);
        if (!file)
                goto out_free;
        ima_counts_get(file);