fat: Fix _fat_bmap() race

[linux-2.6-omap-h63xx.git] / fs / fat / inode.c

diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index f58cd48d98b8e09d352ed92e50792cb98630965e..be88208b83a65e39477459c96dcd9a1f86c4a641 100644 (file)
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -199,7 +199,14 @@ static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
 
 static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
 {
-       return generic_block_bmap(mapping, block, fat_get_block);
+       sector_t blocknr;
+
+       /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
+       mutex_lock(&mapping->host->i_mutex);
+       blocknr = generic_block_bmap(mapping, block, fat_get_block);
+       mutex_unlock(&mapping->host->i_mutex);
+
+       return blocknr;
 }
 
 static const struct address_space_operations fat_aops = {
@@ -337,8 +344,7 @@ 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 +361,9 @@ 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 +379,8 @@ 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;
 
@@ -429,13 +435,8 @@ static void fat_delete_inode(struct inode *inode)
 
 static void fat_clear_inode(struct inode *inode)
 {
-       struct super_block *sb = inode->i_sb;
-       struct msdos_sb_info *sbi = MSDOS_SB(sb);
-
-       spin_lock(&sbi->inode_hash_lock);
        fat_cache_inval_inode(inode);
-       hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
-       spin_unlock(&sbi->inode_hash_lock);
+       fat_detach(inode);
 }
 
 static void fat_write_super(struct super_block *sb)
@@ -574,7 +575,7 @@ 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,
@@ -803,8 +804,10 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
                        seq_puts(m, ",uni_xlate");
                if (!opts->numtail)
                        seq_puts(m, ",nonumtail");
+               if (opts->rodir)
+                       seq_puts(m, ",rodir");
        }
-       if (sbi->options.flush)
+       if (opts->flush)
                seq_puts(m, ",flush");
        if (opts->tz_utc)
                seq_puts(m, ",tz=UTC");
@@ -820,7 +823,7 @@ enum {
        Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
        Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
        Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
-       Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_err,
+       Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err,
 };
 
 static const match_table_t fat_tokens = {
@@ -892,6 +895,7 @@ static const match_table_t vfat_tokens = {
        {Opt_nonumtail_yes, "nonumtail=yes"},
        {Opt_nonumtail_yes, "nonumtail=true"},
        {Opt_nonumtail_yes, "nonumtail"},
+       {Opt_rodir, "rodir"},
        {Opt_err, NULL}
 };
 
@@ -911,10 +915,13 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
        opts->allow_utime = -1;
        opts->codepage = fat_default_codepage;
        opts->iocharset = fat_default_iocharset;
-       if (is_vfat)
+       if (is_vfat) {
                opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95;
-       else
+               opts->rodir = 0;
+       } else {
                opts->shortname = 0;
+               opts->rodir = 1;
+       }
        opts->name_check = 'n';
        opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK =  0;
        opts->utf8 = opts->unicode_xlate = 0;
@@ -1065,6 +1072,9 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
                case Opt_nonumtail_yes:         /* empty or 1 or yes or true */
                        opts->numtail = 0;      /* negated option */
                        break;
+               case Opt_rodir:
+                       opts->rodir = 1;
+                       break;
 
                /* obsolete mount options */
                case Opt_obsolate:
@@ -1110,7 +1120,7 @@ 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) {
@@ -1127,7 +1137,7 @@ 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;