f2fs: support ->tmpfile()

Add function f2fs_tmpfile() to support O_TMPFILE file creation, and modify logic
of init_inode_metadata to enable linkat temp file.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

2 files changed, 73 insertions, 1 deletions

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index a4addd72ebbd..3677f4124541 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -333,10 +333,12 @@ static int make_empty_dir(struct inode *inode,
 static struct page *init_inode_metadata(struct inode *inode,
                 struct inode *dir, const struct qstr *name)
 {
+        struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
         struct page *page;
         int err;
 
-        if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE)) {
+        if (is_inode_flag_set(F2FS_I(inode), FI_NEW_INODE) &&
+                        inode->i_nlink) {
                 page = new_inode_page(inode, name);
                 if (IS_ERR(page))
                         return page;
@@ -370,6 +372,12 @@ static struct page *init_inode_metadata(struct inode *inode,
          */
         if (is_inode_flag_set(F2FS_I(inode), FI_INC_LINK)) {
                 file_lost_pino(inode);
+                /*
+                 * If link the tmpfile to alias through linkat path,
+                 * we should remove this inode from orphan list.
+                 */
+                if (inode->i_nlink == 0)
+                        remove_orphan_inode(sbi, inode->i_ino);
                 inc_nlink(inode);
         }
         return page;
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index a6bdddc33ce2..5c08c546e4c8 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -13,6 +13,7 @@
 #include <linux/pagemap.h>
 #include <linux/sched.h>
 #include <linux/ctype.h>
+#include <linux/dcache.h>
 
 #include "f2fs.h"
 #include "node.h"
@@ -487,6 +488,68 @@ out:
         return err;
 }
 
+static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
+{
+        struct super_block *sb = dir->i_sb;
+        struct f2fs_sb_info *sbi = F2FS_SB(sb);
+        struct inode *inode;
+        struct page *page;
+        int err;
+
+        inode = f2fs_new_inode(dir, mode);
+        if (IS_ERR(inode))
+                return PTR_ERR(inode);
+
+        inode->i_op = &f2fs_file_inode_operations;
+        inode->i_fop = &f2fs_file_operations;
+        inode->i_mapping->a_ops = &f2fs_dblock_aops;
+
+        f2fs_lock_op(sbi);
+        err = acquire_orphan_inode(sbi);
+        if (err)
+                goto out;
+        /*
+         * add this non-linked tmpfile to orphan list, in this way we could
+         * remove all unused data of tmpfile after abnormal power-off.
+         */
+        add_orphan_inode(sbi, inode->i_ino);
+
+        page = new_inode_page(inode, NULL);
+        if (IS_ERR(page)) {
+                err = PTR_ERR(page);
+                goto remove_out;
+        }
+
+        err = f2fs_init_acl(inode, dir, page);
+        if (err)
+                goto unlock_out;
+
+        err = f2fs_init_security(inode, dir, NULL, page);
+        if (err)
+                goto unlock_out;
+
+        f2fs_put_page(page, 1);
+        f2fs_unlock_op(sbi);
+
+        alloc_nid_done(sbi, inode->i_ino);
+        mark_inode_dirty(inode);
+        d_tmpfile(dentry, inode);
+        unlock_new_inode(inode);
+        return 0;
+unlock_out:
+        f2fs_put_page(page, 1);
+remove_out:
+        remove_orphan_inode(sbi, inode->i_ino);
+out:
+        f2fs_unlock_op(sbi);
+        clear_nlink(inode);
+        unlock_new_inode(inode);
+        make_bad_inode(inode);
+        iput(inode);
+        alloc_nid_failed(sbi, inode->i_ino);
+        return err;
+}
+
 const struct inode_operations f2fs_dir_inode_operations = {
         .create         = f2fs_create,
         .lookup         = f2fs_lookup,
@@ -497,6 +560,7 @@ const struct inode_operations f2fs_dir_inode_operations = {
         .rmdir          = f2fs_rmdir,
         .mknod          = f2fs_mknod,
         .rename         = f2fs_rename,
+        .tmpfile        = f2fs_tmpfile,
         .getattr        = f2fs_getattr,
         .setattr        = f2fs_setattr,
         .get_acl        = f2fs_get_acl,