uaccess: Add non-pagefault user-space read functions

[people/arne_f/kernel.git] / mm / shmem.c

diff --git a/mm/shmem.c b/mm/shmem.c
index 0b6db162083c8cbd739bc91004c1c42ec1935033..24005c3b345ca80687f841e483bd2a8ad053b4fc 100644 (file)
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2129,7 +2129,11 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
        struct shmem_inode_info *info = SHMEM_I(inode);
        int retval = -ENOMEM;
 
-       spin_lock_irq(&info->lock);
+       /*
+        * What serializes the accesses to info->flags?
+        * ipc_lock_object() when called from shmctl_do_lock(),
+        * no serialization needed when called from shm_destroy().
+        */
        if (lock && !(info->flags & VM_LOCKED)) {
                if (!user_shm_lock(inode->i_size, user))
                        goto out_nomem;
@@ -2144,7 +2148,6 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
        retval = 0;
 
 out_nomem:
-       spin_unlock_irq(&info->lock);
        return retval;
 }
 
@@ -2330,11 +2333,11 @@ static int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
 
        lru_cache_add_anon(page);
 
-       spin_lock(&info->lock);
+       spin_lock_irq(&info->lock);
        info->alloced++;
        inode->i_blocks += BLOCKS_PER_PAGE;
        shmem_recalc_inode(inode);
-       spin_unlock(&info->lock);
+       spin_unlock_irq(&info->lock);
 
        inc_mm_counter(dst_mm, mm_counter_file(page));
        page_add_file_rmap(page, false);