From 8fc2751beb0941966d3a97b26544e8585e428c08 Mon Sep 17 00:00:00 2001 From: Mark Bellon Date: Tue, 6 Sep 2005 15:16:54 -0700 Subject: [PATCH] disk quotas fail when /etc/mtab is symlinked to /proc/mounts If /etc/mtab is a regular file all of the mount options (of a file system) are written to /etc/mtab by the mount command. The quota tools look there for the quota strings for their operation. If, however, /etc/mtab is a symlink to /proc/mounts (a "good thing" in some environments) the tools don't write anything - they assume the kernel will take care of things. While the quota options are sent down to the kernel via the mount system call and the file system codes handle them properly unfortunately there is no code to echo the quota strings into /proc/mounts and the quota tools fail in the symlink case. The attached patchs modify the EXT[2|3] and JFS codes to add the necessary hooks. The show_options function of each file system in these patches currently deal with only those things that seemed related to quotas; especially in the EXT3 case more can be done (later?). Jan Kara also noted the difficulty in moving these changes above the FS codes responding similarly to myself to Andrew's comment about possible VFS migration. Issue summary: - FS codes have to process the entire string of options anyway. - Only FS codes that use quotas must have a show_options function (for quotas to work properly) however quotas are only used in a small number of FS. - Since most of the quota using FS support other options these FS codes should have the a show_options function to show those options - and the quota echoing becomes virtually negligible. Based on feedback I have modified my patches from the original: JFS a missing patch has been restored to the posting EXT[2|3] and JFS always use the show_options function - Each FS has at least one FS specific option displayed - QUOTA output is under a CONFIG_QUOTA ifdef - a follow-on patch will add a multitude of options for each FS EXT[2|3] and JFS "quota" is treated as "usrquota" EXT3 journalled data check for journalled quota removed EXT[2|3] mount when quota specified but not compiled in - no changes from my original patch. I tested the patch and the codes warn but - still mount. With all due respection I believe the comments otherwise were a - misread of the patch. Please reread/test and comment. XFS patch removed - the XFS team already made the necessary changes EXT3 mixing old and new quotas are handled differently (not purely exclusive) - if old and new quotas for the same type are used together the old type is silently depricated for compatability (e.g. usrquota and usrjquota) - mixing of old and new quotas is an error (e.g. usrjquota and grpquota) Signed-off-by: Mark Bellon Acked-by: Dave Kleikamp Cc: Jan Kara Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/jfs/jfs_filsys.h | 3 +++ fs/jfs/super.c | 48 +++++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 48 insertions(+), 3 deletions(-) (limited to 'fs/jfs') diff --git a/fs/jfs/jfs_filsys.h b/fs/jfs/jfs_filsys.h index 86ccac8..72a5588 100644 --- a/fs/jfs/jfs_filsys.h +++ b/fs/jfs/jfs_filsys.h @@ -37,6 +37,9 @@ #define JFS_ERR_CONTINUE 0x00000004 /* continue */ #define JFS_ERR_PANIC 0x00000008 /* panic */ +#define JFS_USRQUOTA 0x00000010 +#define JFS_GRPQUOTA 0x00000020 + /* platform option (conditional compilation) */ #define JFS_AIX 0x80000000 /* AIX support */ /* POSIX name/directory support */ diff --git a/fs/jfs/super.c b/fs/jfs/super.c index 9ff8972..71bc34b 100644 --- a/fs/jfs/super.c +++ b/fs/jfs/super.c @@ -23,9 +23,11 @@ #include #include #include +#include #include #include #include +#include #include "jfs_incore.h" #include "jfs_filsys.h" @@ -192,7 +194,8 @@ static void jfs_put_super(struct super_block *sb) enum { Opt_integrity, Opt_nointegrity, Opt_iocharset, Opt_resize, - Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, + Opt_resize_nosize, Opt_errors, Opt_ignore, Opt_err, Opt_quota, + Opt_usrquota, Opt_grpquota }; static match_table_t tokens = { @@ -204,8 +207,8 @@ static match_table_t tokens = { {Opt_errors, "errors=%s"}, {Opt_ignore, "noquota"}, {Opt_ignore, "quota"}, - {Opt_ignore, "usrquota"}, - {Opt_ignore, "grpquota"}, + {Opt_usrquota, "usrquota"}, + {Opt_grpquota, "grpquota"}, {Opt_err, NULL} }; @@ -293,6 +296,24 @@ static int parse_options(char *options, struct super_block *sb, s64 *newLVSize, } break; } + +#if defined(CONFIG_QUOTA) + case Opt_quota: + case Opt_usrquota: + *flag |= JFS_USRQUOTA; + break; + case Opt_grpquota: + *flag |= JFS_GRPQUOTA; + break; +#else + case Opt_usrquota: + case Opt_grpquota: + case Opt_quota: + printk(KERN_ERR + "JFS: quota operations not supported\n"); + break; +#endif + default: printk("jfs: Unrecognized mount option \"%s\" " " or missing value\n", p); @@ -539,6 +560,26 @@ static int jfs_sync_fs(struct super_block *sb, int wait) return 0; } +static int jfs_show_options(struct seq_file *seq, struct vfsmount *vfs) +{ + struct jfs_sb_info *sbi = JFS_SBI(vfs->mnt_sb); + + if (sbi->flag & JFS_NOINTEGRITY) + seq_puts(seq, ",nointegrity"); + else + seq_puts(seq, ",integrity"); + +#if defined(CONFIG_QUOTA) + if (sbi->flag & JFS_USRQUOTA) + seq_puts(seq, ",usrquota"); + + if (sbi->flag & JFS_GRPQUOTA) + seq_puts(seq, ",grpquota"); +#endif + + return 0; +} + static struct super_operations jfs_super_operations = { .alloc_inode = jfs_alloc_inode, .destroy_inode = jfs_destroy_inode, @@ -552,6 +593,7 @@ static struct super_operations jfs_super_operations = { .unlockfs = jfs_unlockfs, .statfs = jfs_statfs, .remount_fs = jfs_remount, + .show_options = jfs_show_options }; static struct export_operations jfs_export_operations = { -- cgit v1.1