From 28ec039c21839914389975b896160a815ffd8b83 Mon Sep 17 00:00:00 2001 From: OGAWA Hirofumi Date: Tue, 8 May 2007 00:31:01 -0700 Subject: [PATCH] fat: don't use free_clusters for fat32 It seems that the recent Windows changed specification, and it's undocumented. Windows doesn't update ->free_clusters correctly. This patch doesn't use ->free_clusters by default. (instead, add "usefree" for forcing to use it) Signed-off-by: OGAWA Hirofumi Cc: Juergen Beisert Cc: Andreas Schwab Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/filesystems/vfat.txt | 7 +++++++ fs/fat/inode.c | 14 +++++++++++--- include/linux/msdos_fs.h | 3 ++- 3 files changed, 20 insertions(+), 4 deletions(-) diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt index 069cb1094300..fcc123ffa252 100644 --- a/Documentation/filesystems/vfat.txt +++ b/Documentation/filesystems/vfat.txt @@ -57,6 +57,13 @@ nonumtail= -- When creating 8.3 aliases, normally the alias will currently exist in the directory, 'longfile.txt' will be the short alias instead of 'longfi~1.txt'. +usefree -- Use the "free clusters" value stored on FSINFO. It'll + be used to determine number of free clusters without + scanning disk. But it's not used by default, because + recent Windows don't update it correctly in some + case. If you are sure the "free clusters" on FSINFO is + correct, by this option you can avoid scanning disk. + quiet -- Stops printing certain warning messages. check=s|r|n -- Case sensitivity checking setting. diff --git a/fs/fat/inode.c b/fs/fat/inode.c index a8129e82d594..2c55e8dce793 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -825,6 +825,8 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt) } if (opts->name_check != 'n') seq_printf(m, ",check=%c", opts->name_check); + if (opts->usefree) + seq_puts(m, ",usefree"); if (opts->quiet) seq_puts(m, ",quiet"); if (opts->showexec) @@ -850,7 +852,7 @@ static int fat_show_options(struct seq_file *m, struct vfsmount *mnt) enum { Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid, - Opt_umask, Opt_dmask, Opt_fmask, Opt_codepage, Opt_nocase, + Opt_umask, Opt_dmask, Opt_fmask, Opt_codepage, Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug, Opt_immutable, Opt_dots, Opt_nodots, Opt_charset, Opt_shortname_lower, Opt_shortname_win95, @@ -872,6 +874,7 @@ static match_table_t fat_tokens = { {Opt_dmask, "dmask=%o"}, {Opt_fmask, "fmask=%o"}, {Opt_codepage, "codepage=%u"}, + {Opt_usefree, "usefree"}, {Opt_nocase, "nocase"}, {Opt_quiet, "quiet"}, {Opt_showexec, "showexec"}, @@ -951,7 +954,7 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug, opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0; opts->utf8 = opts->unicode_xlate = 0; opts->numtail = 1; - opts->nocase = 0; + opts->usefree = opts->nocase = 0; *debug = 0; if (!options) @@ -979,6 +982,9 @@ static int parse_options(char *options, int is_vfat, int silent, int *debug, case Opt_check_n: opts->name_check = 'n'; break; + case Opt_usefree: + opts->usefree = 1; + break; case Opt_nocase: if (!is_vfat) opts->nocase = 1; @@ -1304,7 +1310,9 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, le32_to_cpu(fsinfo->signature2), sbi->fsinfo_sector); } else { - sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters); + if (sbi->options.usefree) + sbi->free_clusters = + le32_to_cpu(fsinfo->free_clusters); sbi->prev_free = le32_to_cpu(fsinfo->next_cluster); } diff --git a/include/linux/msdos_fs.h b/include/linux/msdos_fs.h index fa253fa73aa3..0e09c005dda8 100644 --- a/include/linux/msdos_fs.h +++ b/include/linux/msdos_fs.h @@ -205,7 +205,8 @@ struct fat_mount_options { numtail:1, /* Does first alias have a numeric '~1' type tail? */ atari:1, /* Use Atari GEMDOS variation of MS-DOS fs */ flush:1, /* write things quickly */ - nocase:1; /* Does this need case conversion? 0=need case conversion*/ + nocase:1, /* Does this need case conversion? 0=need case conversion*/ + usefree:1; /* Use free_clusters for FAT32 */ }; #define FAT_HASH_BITS 8