Merge git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
  fat: split fat_generic_ioctl
  FAT: add 'errors' mount option

10 files changed, 152 insertions, 110 deletions

diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index 5147be5e13cd..b58b84b50fa2 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -132,6 +132,11 @@ rodir	      -- FAT has the ATTR_RO (read-only) attribute. On Windows,
                  If you want to use ATTR_RO as read-only flag even for
                  the directory, set this option.
 
+errors=panic|continue|remount-ro
+              -- specify FAT behavior on critical errors: panic, continue
+                 without doing anything or remount the partition in
+                 read-only mode (default behavior).
+
 <bool>: 0,1,yes,no,true,false
 
 TODO
diff --git a/fs/fat/cache.c b/fs/fat/cache.c
index b42602298087..923990e4f16e 100644
--- a/fs/fat/cache.c
+++ b/fs/fat/cache.c
@@ -241,7 +241,7 @@ int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus)
         while (*fclus < cluster) {
                 /* prevent the infinite loop of cluster chain */
                 if (*fclus > limit) {
-                        fat_fs_panic(sb, "%s: detected the cluster chain loop"
+                        fat_fs_error(sb, "%s: detected the cluster chain loop"
                                      " (i_pos %lld)", __func__,
                                      MSDOS_I(inode)->i_pos);
                         nr = -EIO;
@@ -252,7 +252,7 @@ int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus)
                 if (nr < 0)
                         goto out;
                 else if (nr == FAT_ENT_FREE) {
-                        fat_fs_panic(sb, "%s: invalid cluster chain"
+                        fat_fs_error(sb, "%s: invalid cluster chain"
                                      " (i_pos %lld)", __func__,
                                      MSDOS_I(inode)->i_pos);
                         nr = -EIO;
@@ -285,7 +285,7 @@ static int fat_bmap_cluster(struct inode *inode, int cluster)
         if (ret < 0)
                 return ret;
         else if (ret == FAT_ENT_EOF) {
-                fat_fs_panic(sb, "%s: request beyond EOF (i_pos %lld)",
+                fat_fs_error(sb, "%s: request beyond EOF (i_pos %lld)",
                              __func__, MSDOS_I(inode)->i_pos);
                 return -EIO;
         }
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index f3500294eec5..3b8e71b412fd 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -1334,7 +1334,7 @@ found:
                         goto error_remove;
                 }
                 if (dir->i_size & (sbi->cluster_size - 1)) {
-                        fat_fs_panic(sb, "Odd directory size");
+                        fat_fs_error(sb, "Odd directory size");
                         dir->i_size = (dir->i_size + sbi->cluster_size - 1)
                                 & ~((loff_t)sbi->cluster_size - 1);
                 }
diff --git a/fs/fat/fat.h b/fs/fat/fat.h
index e4d88527b5dd..adb0e72a176d 100644
--- a/fs/fat/fat.h
+++ b/fs/fat/fat.h
@@ -17,6 +17,10 @@
 #define VFAT_SFN_CREATE_WIN95   0x0100 /* emulate win95 rule for create */
 #define VFAT_SFN_CREATE_WINNT   0x0200 /* emulate winnt rule for create */
 
+#define FAT_ERRORS_CONT         1      /* ignore error and continue */
+#define FAT_ERRORS_PANIC        2      /* panic on error */
+#define FAT_ERRORS_RO           3      /* remount r/o on error */
+
 struct fat_mount_options {
         uid_t fs_uid;
         gid_t fs_gid;
@@ -26,6 +30,7 @@ struct fat_mount_options {
         char *iocharset;          /* Charset used for filename input/display */
         unsigned short shortname; /* flags for shortname display/create rule */
         unsigned char name_check; /* r = relaxed, n = normal, s = strict */
+        unsigned char errors;     /* On error: continue, panic, remount-ro */
         unsigned short allow_utime;/* permission for setting the [am]time */
         unsigned quiet:1,         /* set = fake successful chmods and chowns */
                  showexec:1,      /* set = only set x bit for com/exe/bat */
@@ -316,7 +321,7 @@ extern int fat_fill_super(struct super_block *sb, void *data, int silent,
 extern int fat_flush_inodes(struct super_block *sb, struct inode *i1,
                             struct inode *i2);
 /* fat/misc.c */
-extern void fat_fs_panic(struct super_block *s, const char *fmt, ...)
+extern void fat_fs_error(struct super_block *s, const char *fmt, ...)
         __attribute__ ((format (printf, 2, 3))) __cold;
 extern void fat_clusters_flush(struct super_block *sb);
 extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster);
diff --git a/fs/fat/fatent.c b/fs/fat/fatent.c
index 618f5305c2e4..a81037721a6f 100644
--- a/fs/fat/fatent.c
+++ b/fs/fat/fatent.c
@@ -348,7 +348,7 @@ int fat_ent_read(struct inode *inode, struct fat_entry *fatent, int entry)
 
         if (entry < FAT_START_ENT || sbi->max_cluster <= entry) {
                 fatent_brelse(fatent);
-                fat_fs_panic(sb, "invalid access to FAT (entry 0x%08x)", entry);
+                fat_fs_error(sb, "invalid access to FAT (entry 0x%08x)", entry);
                 return -EIO;
         }
 
@@ -560,7 +560,7 @@ int fat_free_clusters(struct inode *inode, int cluster)
                         err = cluster;
                         goto error;
                 } else if (cluster == FAT_ENT_FREE) {
-                        fat_fs_panic(sb, "%s: deleting FAT entry beyond EOF",
+                        fat_fs_error(sb, "%s: deleting FAT entry beyond EOF",
                                      __func__);
                         err = -EIO;
                         goto error;
diff --git a/fs/fat/file.c b/fs/fat/file.c
index e955a56b4e5e..b28ea646ff60 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -18,106 +18,112 @@
 #include <linux/security.h>
 #include "fat.h"
 
-int fat_generic_ioctl(struct inode *inode, struct file *filp,
-                      unsigned int cmd, unsigned long arg)
+static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
 {
+        u32 attr;
+
+        mutex_lock(&inode->i_mutex);
+        attr = fat_make_attrs(inode);
+        mutex_unlock(&inode->i_mutex);
+
+        return put_user(attr, user_attr);
+}
+
+static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
+{
+        struct inode *inode = file->f_path.dentry->d_inode;
         struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
-        u32 __user *user_attr = (u32 __user *)arg;
+        int is_dir = S_ISDIR(inode->i_mode);
+        u32 attr, oldattr;
+        struct iattr ia;
+        int err;
 
-        switch (cmd) {
-        case FAT_IOCTL_GET_ATTRIBUTES:
-        {
-                u32 attr;
+        err = get_user(attr, user_attr);
+        if (err)
+                goto out;
 
-                mutex_lock(&inode->i_mutex);
-                attr = fat_make_attrs(inode);
-                mutex_unlock(&inode->i_mutex);
+        mutex_lock(&inode->i_mutex);
+        err = mnt_want_write(file->f_path.mnt);
+        if (err)
+                goto out_unlock_inode;
 
-                return put_user(attr, user_attr);
+        /*
+         * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
+         * prevents the user from turning us into a VFAT
+         * longname entry.  Also, we obviously can't set
+         * any of the NTFS attributes in the high 24 bits.
+         */
+        attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
+        /* Merge in ATTR_VOLUME and ATTR_DIR */
+        attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
+                (is_dir ? ATTR_DIR : 0);
+        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 = 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));
         }
-        case FAT_IOCTL_SET_ATTRIBUTES:
-        {
-                u32 attr, oldattr;
-                int err, is_dir = S_ISDIR(inode->i_mode);
-                struct iattr ia;
 
-                err = get_user(attr, user_attr);
-                if (err)
-                        return err;
+        /* The root directory has no attributes */
+        if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
+                err = -EINVAL;
+                goto out_drop_write;
+        }
 
-                mutex_lock(&inode->i_mutex);
-
-                err = mnt_want_write(filp->f_path.mnt);
-                if (err)
-                        goto up_no_drop_write;
-
-                /*
-                 * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
-                 * prevents the user from turning us into a VFAT
-                 * longname entry.  Also, we obviously can't set
-                 * any of the NTFS attributes in the high 24 bits.
-                 */
-                attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
-                /* Merge in ATTR_VOLUME and ATTR_DIR */
-                attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
-                        (is_dir ? ATTR_DIR : 0);
-                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 = 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));
-                }
+        if (sbi->options.sys_immutable &&
+            ((attr | oldattr) & ATTR_SYS) &&
+            !capable(CAP_LINUX_IMMUTABLE)) {
+                err = -EPERM;
+                goto out_drop_write;
+        }
 
-                /* The root directory has no attributes */
-                if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
-                        err = -EINVAL;
-                        goto up;
-                }
+        /*
+         * The security check is questionable...  We single
+         * out the RO attribute for checking by the security
+         * module, just because it maps to a file mode.
+         */
+        err = security_inode_setattr(file->f_path.dentry, &ia);
+        if (err)
+                goto out_drop_write;
 
-                if (sbi->options.sys_immutable) {
-                        if ((attr | oldattr) & ATTR_SYS) {
-                                if (!capable(CAP_LINUX_IMMUTABLE)) {
-                                        err = -EPERM;
-                                        goto up;
-                                }
-                        }
-                }
+        /* This MUST be done before doing anything irreversible... */
+        err = fat_setattr(file->f_path.dentry, &ia);
+        if (err)
+                goto out_drop_write;
+
+        fsnotify_change(file->f_path.dentry, ia.ia_valid);
+        if (sbi->options.sys_immutable) {
+                if (attr & ATTR_SYS)
+                        inode->i_flags |= S_IMMUTABLE;
+                else
+                        inode->i_flags &= S_IMMUTABLE;
+        }
 
-                /*
-                 * The security check is questionable...  We single
-                 * out the RO attribute for checking by the security
-                 * module, just because it maps to a file mode.
-                 */
-                err = security_inode_setattr(filp->f_path.dentry, &ia);
-                if (err)
-                        goto up;
-
-                /* This MUST be done before doing anything irreversible... */
-                err = fat_setattr(filp->f_path.dentry, &ia);
-                if (err)
-                        goto up;
-
-                fsnotify_change(filp->f_path.dentry, ia.ia_valid);
-                if (sbi->options.sys_immutable) {
-                        if (attr & ATTR_SYS)
-                                inode->i_flags |= S_IMMUTABLE;
-                        else
-                                inode->i_flags &= S_IMMUTABLE;
-                }
+        fat_save_attrs(inode, attr);
+        mark_inode_dirty(inode);
+out_drop_write:
+        mnt_drop_write(file->f_path.mnt);
+out_unlock_inode:
+        mutex_unlock(&inode->i_mutex);
+out:
+        return err;
+}
 
-                fat_save_attrs(inode, attr);
-                mark_inode_dirty(inode);
-up:
-                mnt_drop_write(filp->f_path.mnt);
-up_no_drop_write:
-                mutex_unlock(&inode->i_mutex);
-                return err;
-        }
+int fat_generic_ioctl(struct inode *inode, struct file *filp,
+                      unsigned int cmd, unsigned long arg)
+{
+        u32 __user *user_attr = (u32 __user *)arg;
+
+        switch (cmd) {
+        case FAT_IOCTL_GET_ATTRIBUTES:
+                return fat_ioctl_get_attributes(inode, user_attr);
+        case FAT_IOCTL_SET_ATTRIBUTES:
+                return fat_ioctl_set_attributes(filp, user_attr);
         default:
                 return -ENOTTY; /* Inappropriate ioctl for device */
         }
@@ -225,7 +231,7 @@ static int fat_free(struct inode *inode, int skip)
                         fatent_brelse(&fatent);
                         return 0;
                 } else if (ret == FAT_ENT_FREE) {
-                        fat_fs_panic(sb,
+                        fat_fs_error(sb,
                                      "%s: invalid cluster chain (i_pos %lld)",
                                      __func__, MSDOS_I(inode)->i_pos);
                         ret = -EIO;
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
index 51a5ecf9000a..304b411cb8bc 100644
--- a/fs/fat/inode.c
+++ b/fs/fat/inode.c
@@ -76,7 +76,7 @@ static inline int __fat_get_block(struct inode *inode, sector_t iblock,
                 return 0;
 
         if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
-                fat_fs_panic(sb, "corrupted file size (i_pos %lld, %lld)",
+                fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)",
                         MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
                 return -EIO;
         }
@@ -856,6 +856,12 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
                 seq_puts(m, ",flush");
         if (opts->tz_utc)
                 seq_puts(m, ",tz=UTC");
+        if (opts->errors == FAT_ERRORS_CONT)
+                seq_puts(m, ",errors=continue");
+        else if (opts->errors == FAT_ERRORS_PANIC)
+                seq_puts(m, ",errors=panic");
+        else
+                seq_puts(m, ",errors=remount-ro");
 
         return 0;
 }
@@ -868,7 +874,8 @@ 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_rodir, Opt_err,
+        Opt_obsolate, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont,
+        Opt_err_panic, Opt_err_ro, Opt_err,
 };
 
 static const match_table_t fat_tokens = {
@@ -891,6 +898,11 @@ static const match_table_t fat_tokens = {
         {Opt_showexec, "showexec"},
         {Opt_debug, "debug"},
         {Opt_immutable, "sys_immutable"},
+        {Opt_flush, "flush"},
+        {Opt_tz_utc, "tz=UTC"},
+        {Opt_err_cont, "errors=continue"},
+        {Opt_err_panic, "errors=panic"},
+        {Opt_err_ro, "errors=remount-ro"},
         {Opt_obsolate, "conv=binary"},
         {Opt_obsolate, "conv=text"},
         {Opt_obsolate, "conv=auto"},
@@ -902,8 +914,6 @@ static const match_table_t fat_tokens = {
         {Opt_obsolate, "cvf_format=%20s"},
         {Opt_obsolate, "cvf_options=%100s"},
         {Opt_obsolate, "posix"},
-        {Opt_flush, "flush"},
-        {Opt_tz_utc, "tz=UTC"},
         {Opt_err, NULL},
 };
 static const match_table_t msdos_tokens = {
@@ -973,6 +983,7 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
         opts->numtail = 1;
         opts->usefree = opts->nocase = 0;
         opts->tz_utc = 0;
+        opts->errors = FAT_ERRORS_RO;
         *debug = 0;
 
         if (!options)
@@ -1065,6 +1076,15 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug,
                 case Opt_tz_utc:
                         opts->tz_utc = 1;
                         break;
+                case Opt_err_cont:
+                        opts->errors = FAT_ERRORS_CONT;
+                        break;
+                case Opt_err_panic:
+                        opts->errors = FAT_ERRORS_PANIC;
+                        break;
+                case Opt_err_ro:
+                        opts->errors = FAT_ERRORS_RO;
+                        break;
 
                 /* msdos specific */
                 case Opt_dots:
diff --git a/fs/fat/misc.c b/fs/fat/misc.c
index ac39ebcc1496..a6c20473dfd7 100644
--- a/fs/fat/misc.c
+++ b/fs/fat/misc.c
@@ -12,14 +12,19 @@
 #include "fat.h"
 
 /*
- * fat_fs_panic reports a severe file system problem and sets the file system
- * read-only. The file system can be made writable again by remounting it.
+ * fat_fs_error reports a file system problem that might indicate fa data
+ * corruption/inconsistency. Depending on 'errors' mount option the
+ * panic() is called, or error message is printed FAT and nothing is done,
+ * or filesystem is remounted read-only (default behavior).
+ * In case the file system is remounted read-only, it can be made writable
+ * again by remounting it.
  */
-void fat_fs_panic(struct super_block *s, const char *fmt, ...)
+void fat_fs_error(struct super_block *s, const char *fmt, ...)
 {
+        struct fat_mount_options *opts = &MSDOS_SB(s)->options;
         va_list args;
 
-        printk(KERN_ERR "FAT: Filesystem panic (dev %s)\n", s->s_id);
+        printk(KERN_ERR "FAT: Filesystem error (dev %s)\n", s->s_id);
 
         printk(KERN_ERR "    ");
         va_start(args, fmt);
@@ -27,13 +32,14 @@ void fat_fs_panic(struct super_block *s, const char *fmt, ...)
         va_end(args);
         printk("\n");
 
-        if (!(s->s_flags & MS_RDONLY)) {
+        if (opts->errors == FAT_ERRORS_PANIC)
+                panic("    FAT fs panic from previous error\n");
+        else if (opts->errors == FAT_ERRORS_RO && !(s->s_flags & MS_RDONLY)) {
                 s->s_flags |= MS_RDONLY;
                 printk(KERN_ERR "    File system has been set read-only\n");
         }
 }
-
-EXPORT_SYMBOL_GPL(fat_fs_panic);
+EXPORT_SYMBOL_GPL(fat_fs_error);
 
 /* Flushes the number of free clusters on FAT32 */
 /* XXX: Need to write one per FSINFO block.  Currently only writes 1 */
@@ -124,7 +130,7 @@ int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster)
                         mark_inode_dirty(inode);
         }
         if (new_fclus != (inode->i_blocks >> (sbi->cluster_bits - 9))) {
-                fat_fs_panic(sb, "clusters badly computed (%d != %llu)",
+                fat_fs_error(sb, "clusters badly computed (%d != %llu)",
                              new_fclus,
                              (llu)(inode->i_blocks >> (sbi->cluster_bits - 9)));
                 fat_cache_inval_inode(inode);
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index 20f522861355..82f88733b681 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -608,7 +608,7 @@ error_inode:
                 sinfo.bh = NULL;
         }
         if (corrupt < 0) {
-                fat_fs_panic(new_dir->i_sb,
+                fat_fs_error(new_dir->i_sb,
                              "%s: Filesystem corrupted (i_pos %lld)",
                              __func__, sinfo.i_pos);
         }
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index b50ecbe97f83..8d6fdcfd41df 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -1030,7 +1030,7 @@ error_inode:
                 sinfo.bh = NULL;
         }
         if (corrupt < 0) {
-                fat_fs_panic(new_dir->i_sb,
+                fat_fs_error(new_dir->i_sb,
                              "%s: Filesystem corrupted (i_pos %lld)",
                              __func__, sinfo.i_pos);
         }