xfs
[Top] [All Lists]

Re: [PATCH] xfs_fsr: use /proc/mounts if available

To: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Subject: Re: [PATCH] xfs_fsr: use /proc/mounts if available
From: Eric Sandeen <sandeen@xxxxxxxxxxx>
Date: Sun, 12 Sep 2010 23:35:31 -0500
Cc: xfs@xxxxxxxxxxx
In-reply-to: <20100912163428.GA10843@xxxxxxxxxxxxx>
References: <20100912163428.GA10843@xxxxxxxxxxxxx>
User-agent: Thunderbird 2.0.0.24 (Macintosh/20100228)
Christoph Hellwig wrote:
> Prefer /proc/mounts if it exists over /etc/mtab to get a correct picture
> of the kernels mount table for this process.  This works arounds some
> userspace like pam_mount polluting /etc/mtab with incorrect entries.
> 
> Also remove the "mtab" global variable and instead pass it explicitly
> to fsrallfs, like we already do for other functions.
> 
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>

Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxxx>

> Index: xfsprogs-dev/fsr/xfs_fsr.c
> ===================================================================
> --- xfsprogs-dev.orig/fsr/xfs_fsr.c   2010-09-11 20:06:15.000000000 +0000
> +++ xfsprogs-dev/fsr/xfs_fsr.c        2010-09-12 16:28:17.000000000 +0000
> @@ -42,7 +42,9 @@
>  #define XFS_XFLAG_NODEFRAG 0x00002000 /* src dependancy, remove later */
>  #endif
>  
> -#define _PATH_FSRLAST        "/var/tmp/.fsrlast_xfs"
> +#define _PATH_FSRLAST                "/var/tmp/.fsrlast_xfs"
> +#define _PATH_PROC_MOUNTS    "/proc/mounts"
> +
>  
>  char *progname;
>  
> @@ -79,7 +81,6 @@ static __int64_t    minimumfree = 2048;
>  
>  static time_t howlong = 7200;                /* default seconds of 
> reorganizing */
>  static char *leftofffile = _PATH_FSRLAST; /* where we left off last */
> -static char *mtab = MOUNTED;
>  static time_t endtime;
>  static time_t starttime;
>  static xfs_ino_t     leftoffino = 0;
> @@ -94,7 +95,7 @@ static int  packfile(char *fname, char *
>  static void fsrdir(char *dirname);
>  static int  fsrfs(char *mntdir, xfs_ino_t ino, int targetrange);
>  static void initallfs(char *mtab);
> -static void fsrallfs(int howlong, char *leftofffile);
> +static void fsrallfs(char *mtab, int howlong, char *leftofffile);
>  static void fsrall_cleanup(int timeout);
>  static int  getnextents(int);
>  int xfsrtextsize(int fd);
> @@ -187,6 +188,7 @@ main(int argc, char **argv)
>       struct mntent mntpref;
>       register struct mntent *mntp;
>       struct mntent ment;
> +     char *mtab = NULL;
>       register FILE *mtabp;
>  
>       setlinebuf(stdout);
> @@ -198,7 +200,7 @@ main(int argc, char **argv)
>  
>       gflag = ! isatty(0);
>  
> -     while ((c = getopt(argc, argv, "C:p:e:MgsdnvTt:f:m:b:N:FV")) != -1 )
> +     while ((c = getopt(argc, argv, "C:p:e:MgsdnvTt:f:m:b:N:FV")) != -1) {
>               switch (c) {
>               case 'M':
>                       Mflag = 1;
> @@ -250,6 +252,22 @@ main(int argc, char **argv)
>               default:
>                       usage(1);
>               }
> +     }
> +
> +     /*
> +      * If the user did not specify an explicit mount table, try to use
> +      * /proc/mounts if it is available, else /etc/mtab.  We prefer
> +      * /proc/mounts because it is kernel controlled, while /etc/mtab
> +      * may contain garbage that userspace tools like pam_mounts wrote
> +      * into it.
> +      */
> +     if (!mtab) {
> +             if (access(_PATH_PROC_MOUNTS, R_OK) == 0)
> +                     mtab = _PATH_PROC_MOUNTS;
> +             else
> +                     mtab = _PATH_MOUNTED;
> +     }
> +
>       if (vflag)
>               setbuf(stdout, NULL);
>  
> @@ -330,7 +348,7 @@ main(int argc, char **argv)
>               }
>       } else {
>               initallfs(mtab);
> -             fsrallfs(howlong, leftofffile);
> +             fsrallfs(mtab, howlong, leftofffile);
>       }
>       return 0;
>  }
> @@ -447,7 +465,7 @@ initallfs(char *mtab)
>  }
>  
>  static void
> -fsrallfs(int howlong, char *leftofffile)
> +fsrallfs(char *mtab, int howlong, char *leftofffile)
>  {
>       int fd;
>       int error;
> 
> _______________________________________________
> xfs mailing list
> xfs@xxxxxxxxxxx
> http://oss.sgi.com/mailman/listinfo/xfs
> 

<Prev in Thread] Current Thread [Next in Thread>