fat: Cleanup FAT attribute stuff

This adds three helpers:

fat_make_attrs() - makes FAT attributes from inode.
fat_make_mode()  - makes mode_t from FAT attributes.
fat_save_attrs() - saves FAT attributes to inode.

Then this replaces: MSDOS_MKMODE() by fat_make_mode(), fat_attr() by
fat_make_attrs(), ->i_attrs = attr & ATTR_UNUSED by fat_save_attrs().
And for root inode, those is used with ATTR_DIR instead of bogus
ATTR_NONE.

Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 40 insertions, 31 deletions

diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index 2b8e94c3eef4..3b4753a024e3 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -117,14 +117,32 @@ static inline struct msdos_inode_info *MSDOS_I(struct inode *inode)
         return container_of(inode, struct msdos_inode_info, vfs_inode);
 }
 
+/* Convert attribute bits and a mask to the UNIX mode. */
+static inline mode_t fat_make_mode(struct msdos_sb_info *sbi,
+                                   u8 attrs, mode_t mode)
+{
+        if (attrs & ATTR_RO)
+                mode &= ~S_IWUGO;
+
+        if (attrs & ATTR_DIR)
+                return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
+        else
+                return (mode & ~sbi->options.fs_fmask) | S_IFREG;
+}
+
 /* Return the FAT attribute byte for this inode */
-static inline u8 fat_attr(struct inode *inode)
+static inline u8 fat_make_attrs(struct inode *inode)
 {
         return ((inode->i_mode & S_IWUGO) ? ATTR_NONE : ATTR_RO) |
                 (S_ISDIR(inode->i_mode) ? ATTR_DIR : ATTR_NONE) |
                 MSDOS_I(inode)->i_attrs;
 }
 
+static inline void fat_save_attrs(struct inode *inode, u8 attrs)
+{
+        MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED;
+}
+
 static inline unsigned char fat_checksum(const __u8 *name)
 {
         unsigned char s = name[0];
diff --git a/fs/fat/file.c b/fs/fat/file.c
index b21973f266a1..f5a7e907a8fa 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -27,13 +27,7 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
         switch (cmd) {
         case FAT_IOCTL_GET_ATTRIBUTES:
         {
-                u32 attr;
-
-                if (inode->i_ino == MSDOS_ROOT_INO)
-                        attr = ATTR_DIR;
-                else
-                        attr = fat_attr(inode);
-
+                u32 attr = fat_make_attrs(inode);
                 return put_user(attr, user_attr);
         }
         case FAT_IOCTL_SET_ATTRIBUTES:
@@ -62,20 +56,16 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
                 /* Merge in ATTR_VOLUME and ATTR_DIR */
                 attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
                         (is_dir ? ATTR_DIR : 0);
-                oldattr = fat_attr(inode);
+                oldattr = fat_make_attrs(inode);
 
                 /* Equivalent to a chmod() */
                 ia.ia_valid = ATTR_MODE | ATTR_CTIME;
                 ia.ia_ctime = current_fs_time(inode->i_sb);
-                if (is_dir) {
-                        ia.ia_mode = MSDOS_MKMODE(attr,
-                                S_IRWXUGO & ~sbi->options.fs_dmask)
-                                | S_IFDIR;
-                } else {
-                        ia.ia_mode = MSDOS_MKMODE(attr,
-                                (S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO))
-                                & ~sbi->options.fs_fmask)
-                                | S_IFREG;
+                if (is_dir)
+                        ia.ia_mode = fat_make_mode(sbi, attr, S_IRWXUGO);
+                else {
+                        ia.ia_mode = fat_make_mode(sbi, attr,
+                                S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO));
                 }
 
                 /* The root directory has no attributes */
@@ -115,7 +105,7 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
                                 inode->i_flags &= S_IMMUTABLE;
                 }
 
-                MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
+                fat_save_attrs(inode, attr);
                 mark_inode_dirty(inode);
 up:
                 mnt_drop_write(filp->f_path.mnt);
@@ -274,7 +264,7 @@ static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
 
         /*
          * Note, the basic check is already done by a caller of
-         * (attr->ia_mode & ~MSDOS_VALID_MODE)
+         * (attr->ia_mode & ~FAT_VALID_MODE)
          */
 
         if (S_ISREG(inode->i_mode))
@@ -314,6 +304,8 @@ static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
 }
 
 #define TIMES_SET_FLAGS (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)
+/* valid file mode bits */
+#define FAT_VALID_MODE  (S_IFREG | S_IFDIR | S_IRWXUGO)
 
 int fat_setattr(struct dentry *dentry, struct iattr *attr)
 {
@@ -356,7 +348,7 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr)
             ((attr->ia_valid & ATTR_GID) &&
              (attr->ia_gid != sbi->options.fs_gid)) ||
             ((attr->ia_valid & ATTR_MODE) &&
-             (attr->ia_mode & ~MSDOS_VALID_MODE)))
+             (attr->ia_mode & ~FAT_VALID_MODE)))
                 error = -EPERM;
 
         if (error) {
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 8e1b75c63c7f..7aaa21cf019a 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -337,8 +337,7 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
 
         if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
                 inode->i_generation &= ~1;
-                inode->i_mode = MSDOS_MKMODE(de->attr,
-                        S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR;
+                inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
                 inode->i_op = sbi->dir_ops;
                 inode->i_fop = &fat_dir_operations;
 
@@ -355,10 +354,9 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
                 inode->i_nlink = fat_subdirs(inode);
         } else { /* not a directory */
                 inode->i_generation |= 1;
-                inode->i_mode = MSDOS_MKMODE(de->attr,
-                    ((sbi->options.showexec && !is_exec(de->name + 8))
-                        ? S_IRUGO|S_IWUGO : S_IRWXUGO)
-                    & ~sbi->options.fs_fmask) | S_IFREG;
+                inode->i_mode = fat_make_mode(sbi, de->attr,
+                        ((sbi->options.showexec && !is_exec(de->name + 8))
+                         ? S_IRUGO|S_IWUGO : S_IRWXUGO));
                 MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
                 if (sbi->fat_bits == 32)
                         MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
@@ -374,7 +372,8 @@ static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
                 if (sbi->options.sys_immutable)
                         inode->i_flags |= S_IMMUTABLE;
         }
-        MSDOS_I(inode)->i_attrs = de->attr & ATTR_UNUSED;
+        fat_save_attrs(inode, de->attr);
+
         inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
                            & ~((loff_t)sbi->cluster_size - 1)) >> 9;
 
@@ -569,7 +568,7 @@ retry:
                 raw_entry->size = 0;
         else
                 raw_entry->size = cpu_to_le32(inode->i_size);
-        raw_entry->attr = fat_attr(inode);
+        raw_entry->attr = fat_make_attrs(inode);
         raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
         raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
         fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
@@ -1105,7 +1104,7 @@ static int fat_read_root(struct inode *inode)
         inode->i_gid = sbi->options.fs_gid;
         inode->i_version++;
         inode->i_generation = 0;
-        inode->i_mode = (S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR;
+        inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
         inode->i_op = sbi->dir_ops;
         inode->i_fop = &fat_dir_operations;
         if (sbi->fat_bits == 32) {
@@ -1122,7 +1121,7 @@ static int fat_read_root(struct inode *inode)
         MSDOS_I(inode)->i_logstart = 0;
         MSDOS_I(inode)->mmu_private = inode->i_size;
 
-        MSDOS_I(inode)->i_attrs = ATTR_NONE;
+        fat_save_attrs(inode, ATTR_DIR);
         inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
         inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
         inode->i_nlink = fat_subdirs(inode)+2;