1 files changed, 21 insertions, 47 deletions

diff --git a/mm/shmem.c b/mm/shmem.c
index 41b9bbf24e16..0376c124b043 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -29,6 +29,7 @@
 #include <linux/pagemap.h>
 #include <linux/file.h>
 #include <linux/mm.h>
+#include <linux/random.h>
 #include <linux/sched/signal.h>
 #include <linux/export.h>
 #include <linux/swap.h>
@@ -123,7 +124,7 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
 static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
 		struct page **pagep, enum sgp_type sgp,
 		gfp_t gfp, struct vm_area_struct *vma,
-		struct vm_fault *vmf, int *fault_type);
+		struct vm_fault *vmf, vm_fault_t *fault_type);
 
 int shmem_getpage(struct inode *inode, pgoff_t index,
 		struct page **pagep, enum sgp_type sgp)
@@ -1239,8 +1240,8 @@ int shmem_unuse(swp_entry_t swap, struct page *page)
 	 * the shmem_swaplist_mutex which might hold up shmem_writepage().
 	 * Charged back to the user (not to caller) when swap account is used.
 	 */
-	error = mem_cgroup_try_charge(page, current->mm, GFP_KERNEL, &memcg,
-			false);
+	error = mem_cgroup_try_charge_delay(page, current->mm, GFP_KERNEL,
+					    &memcg, false);
 	if (error)
 		goto out;
 	/* No radix_tree_preload: swap entry keeps a place for page in tree */
@@ -1420,7 +1421,6 @@ static void shmem_pseudo_vma_init(struct vm_area_struct *vma,
 		struct shmem_inode_info *info, pgoff_t index)
 {
 	/* Create a pseudo vma that just contains the policy */
-	memset(vma, 0, sizeof(*vma));
 	vma_init(vma, NULL);
 	/* Bias interleave by inode number to distribute better across nodes */
 	vma->vm_pgoff = index + info->vfs_inode.i_ino;
@@ -1620,7 +1620,8 @@ static int shmem_replace_page(struct page **pagep, gfp_t gfp,
  */
 static int shmem_getpage_gfp(struct inode *inode, pgoff_t index,
 	struct page **pagep, enum sgp_type sgp, gfp_t gfp,
-	struct vm_area_struct *vma, struct vm_fault *vmf, int *fault_type)
+	struct vm_area_struct *vma, struct vm_fault *vmf,
+			vm_fault_t *fault_type)
 {
 	struct address_space *mapping = inode->i_mapping;
 	struct shmem_inode_info *info = SHMEM_I(inode);
@@ -1713,7 +1714,7 @@ repeat:
 				goto failed;
 		}
 
-		error = mem_cgroup_try_charge(page, charge_mm, gfp, &memcg,
+		error = mem_cgroup_try_charge_delay(page, charge_mm, gfp, &memcg,
 				false);
 		if (!error) {
 			error = shmem_add_to_page_cache(page, mapping, index,
@@ -1819,7 +1820,7 @@ alloc_nohuge:		page = shmem_alloc_and_acct_page(gfp, inode,
 		if (sgp == SGP_WRITE)
 			__SetPageReferenced(page);
 
-		error = mem_cgroup_try_charge(page, charge_mm, gfp, &memcg,
+		error = mem_cgroup_try_charge_delay(page, charge_mm, gfp, &memcg,
 				PageTransHuge(page));
 		if (error)
 			goto unacct;
@@ -2188,7 +2189,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode
 		inode_init_owner(inode, dir, mode);
 		inode->i_blocks = 0;
 		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
-		inode->i_generation = get_seconds();
+		inode->i_generation = prandom_u32();
 		info = SHMEM_I(inode);
 		memset(info, 0, (char *)inode - (char *)info);
 		spin_lock_init(&info->lock);
@@ -2292,7 +2293,7 @@ static int shmem_mfill_atomic_pte(struct mm_struct *dst_mm,
 	__SetPageSwapBacked(page);
 	__SetPageUptodate(page);
 
-	ret = mem_cgroup_try_charge(page, dst_mm, gfp, &memcg, false);
+	ret = mem_cgroup_try_charge_delay(page, dst_mm, gfp, &memcg, false);
 	if (ret)
 		goto out_release;
 
@@ -3897,18 +3898,11 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);
 
 /* common code */
 
-static const struct dentry_operations anon_ops = {
-	.d_dname = simple_dname
-};
-
 static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, loff_t size,
 				       unsigned long flags, unsigned int i_flags)
 {
-	struct file *res;
 	struct inode *inode;
-	struct path path;
-	struct super_block *sb;
-	struct qstr this;
+	struct file *res;
 
 	if (IS_ERR(mnt))
 		return ERR_CAST(mnt);
@@ -3919,41 +3913,21 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
 	if (shmem_acct_size(flags, size))
 		return ERR_PTR(-ENOMEM);
 
-	res = ERR_PTR(-ENOMEM);
-	this.name = name;
-	this.len = strlen(name);
-	this.hash = 0; /* will go */
-	sb = mnt->mnt_sb;
-	path.mnt = mntget(mnt);
-	path.dentry = d_alloc_pseudo(sb, &this);
-	if (!path.dentry)
-		goto put_memory;
-	d_set_d_op(path.dentry, &anon_ops);
-
-	res = ERR_PTR(-ENOSPC);
-	inode = shmem_get_inode(sb, NULL, S_IFREG | 0777, 0, flags);
-	if (!inode)
-		goto put_memory;
-
+	inode = shmem_get_inode(mnt->mnt_sb, NULL, S_IFREG | S_IRWXUGO, 0,
+				flags);
+	if (unlikely(!inode)) {
+		shmem_unacct_size(flags, size);
+		return ERR_PTR(-ENOSPC);
+	}
 	inode->i_flags |= i_flags;
-	d_instantiate(path.dentry, inode);
 	inode->i_size = size;
 	clear_nlink(inode);	/* It is unlinked */
 	res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size));
+	if (!IS_ERR(res))
+		res = alloc_file_pseudo(inode, mnt, name, O_RDWR,
+				&shmem_file_operations);
 	if (IS_ERR(res))
-		goto put_path;
-
-	res = alloc_file(&path, FMODE_WRITE | FMODE_READ,
-		  &shmem_file_operations);
-	if (IS_ERR(res))
-		goto put_path;
-
-	return res;
-
-put_memory:
-	shmem_unacct_size(flags, size);
-put_path:
-	path_put(&path);
+		iput(inode);
 	return res;
 }