On 05/11/2013 05:21 AM, Chandra Seetharaman wrote: > Added appropriate pads and code for backward compatibility. > > Copied over the old version as it is different from the newer padded > version. > > New callers of the system call have to just set the version of the data > structure being passed, and kernel will fill as much data as requested. > > Signed-off-by: Chandra Seetharaman <sekharan@xxxxxxxxxx> > --- > fs/gfs2/quota.c | 3 --- > fs/quota/quota.c | 40 ++++++++++++++++++++++++++++++++++++++-- > fs/xfs/xfs_qm_syscalls.c | 4 ---- > include/uapi/linux/dqblk_xfs.h | 38 ++++++++++++++++++++++++++++++++++++-- > 4 files changed, 74 insertions(+), 11 deletions(-) > > diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c > index c7c840e..ca0dccd 100644 > --- a/fs/gfs2/quota.c > +++ b/fs/gfs2/quota.c > @@ -1443,9 +1443,6 @@ static int gfs2_quota_get_xstate(struct super_block *sb, > { > struct gfs2_sbd *sdp = sb->s_fs_info; > > - memset(fqs, 0, sizeof(struct fs_quota_stat)); > - fqs->qs_version = FS_QSTAT_VERSION; > - > switch (sdp->sd_args.ar_quota) { > case GFS2_QUOTA_ON: > fqs->qs_flags |= (FS_QUOTA_UDQ_ENFD | FS_QUOTA_GDQ_ENFD); > diff --git a/fs/quota/quota.c b/fs/quota/quota.c > index c7314f1..510464e 100644 > --- a/fs/quota/quota.c > +++ b/fs/quota/quota.c > @@ -207,12 +207,48 @@ static int quota_setxstate(struct super_block *sb, int cmd, void __user *addr) > static int quota_getxstate(struct super_block *sb, void __user *addr) > { > struct fs_quota_stat fqs; > - int ret; > + struct fs_quota_stat_v1 fqs_v1; > + int ret, size; > + void *cp = &fqs; > > if (!sb->s_qcop->get_xstate) > return -ENOSYS; > + > + memset(&fqs, 0, sizeof(struct fs_quota_stat)); > + if (copy_from_user(&fqs, addr, 1)) /* just get the version */ > + return -EFAULT; > + > + switch (fqs.qs_version) { > + case FS_QSTAT_VERSION_2: > + size = FS_QSTAT_V2_SIZE; > + break; > + default: > + fqs.qs_version = FS_QSTAT_VERSION; > + /* fallthrough */ > + case FS_QSTAT_VERSION: > + size = FS_QSTAT_V1_SIZE; > + cp = &fqs_v1; > + } > + > ret = sb->s_qcop->get_xstate(sb, &fqs); > - if (!ret && copy_to_user(addr, &fqs, sizeof(fqs))) > + if (ret) > + return ret; > + > + if (fqs.qs_version == FS_QSTAT_VERSION) { > + fqs_v1.qs_version = fqs.qs_version; > + fqs_v1.qs_flags = fqs.qs_flags; > + fqs_v1.qs_pad = 0; > + fqs_v1.qs_uquota = fqs.qs_uquota; > + fqs_v1.qs_gquota = fqs.qs_gquota; > + fqs_v1.qs_incoredqs = fqs.qs_incoredqs; > + fqs_v1.qs_btimelimit = fqs.qs_btimelimit; > + fqs_v1.qs_itimelimit = fqs.qs_itimelimit; > + fqs_v1.qs_rtbtimelimit = fqs.qs_rtbtimelimit; > + fqs_v1.qs_bwarnlimit = fqs.qs_bwarnlimit; > + fqs_v1.qs_iwarnlimit = fqs.qs_iwarnlimit; > + } > + > + if (copy_to_user(addr, &cp, size)) > return -EFAULT; > return ret; > } > diff --git a/fs/xfs/xfs_qm_syscalls.c b/fs/xfs/xfs_qm_syscalls.c > index 65c0a7d..c27b0e4 100644 > --- a/fs/xfs/xfs_qm_syscalls.c > +++ b/fs/xfs/xfs_qm_syscalls.c > @@ -420,9 +420,6 @@ xfs_qm_scall_getqstat( > bool tempgqip = false; > bool temppqip = false; > > - memset(out, 0, sizeof(fs_quota_stat_t)); > - > - out->qs_version = FS_QSTAT_VERSION; > if (!xfs_sb_version_hasquota(&mp->m_sb)) { > out->qs_uquota.qfs_ino = NULLFSINO; > out->qs_gquota.qfs_ino = NULLFSINO; > @@ -432,7 +429,6 @@ xfs_qm_scall_getqstat( > out->qs_flags = (__uint16_t) xfs_qm_export_flags(mp->m_qflags & > (XFS_ALL_QUOTA_ACCT| > XFS_ALL_QUOTA_ENFD)); > - out->qs_pad = 0; > out->qs_uquota.qfs_ino = mp->m_sb.sb_uquotino; > out->qs_gquota.qfs_ino = mp->m_sb.sb_gquotino; > if (&out->qs_gquota != &out->qs_pquota) > diff --git a/include/uapi/linux/dqblk_xfs.h b/include/uapi/linux/dqblk_xfs.h > index f17e3bb..d9629c1 100644 > --- a/include/uapi/linux/dqblk_xfs.h > +++ b/include/uapi/linux/dqblk_xfs.h > @@ -18,6 +18,7 @@ > #define _LINUX_DQBLK_XFS_H > > #include <linux/types.h> > +#include <linux/stddef.h> > > /* > * Disk quota - quotactl(2) commands for the XFS Quota Manager (XQM). > @@ -137,8 +138,12 @@ typedef struct fs_disk_quota { > * Provides a centralized way to get meta information about the quota subsystem. > * eg. space taken up for user and group quotas, number of dquots currently > * incore. > + * User space caller should set qs_version to the appropriate version > + * of the fs_quota_stat data structure they are providing. Not providing > + * a version will be treated as FS_QSTAT_VERSION. > */ > #define FS_QSTAT_VERSION 1 /* fs_quota_stat.qs_version */ > +#define FS_QSTAT_VERSION_2 2 /* new field qs_pquota */ > > /* > * Some basic information about 'quota files'. > @@ -149,19 +154,48 @@ typedef struct fs_qfilestat { > __u32 qfs_nextents; /* number of extents */ > } fs_qfilestat_t; > > +typedef struct fs_quota_stat_v1 { > + __s8 qs_version; /* version number for future changes */ > + __u16 qs_flags; /* FS_QUOTA_{U,P,G}DQ_{ACCT,ENFD} */ > + __u8 qs_pad; /* unused */ > + fs_qfilestat_t qs_uquota; /* user quota storage information */ > + fs_qfilestat_t qs_gquota; /* group quota storage information */ > + __u32 qs_incoredqs; /* number of dquots incore */ > + __s32 qs_btimelimit; /* limit for blks timer */ > + __s32 qs_itimelimit; /* limit for inodes timer */ > + __s32 qs_rtbtimelimit;/* limit for rt blks timer */ > + __u16 qs_bwarnlimit; /* limit for num warnings */ > + __u16 qs_iwarnlimit; /* limit for num warnings */ > +} fs_quota_stat_v1_t; Dave has mentioned that we should not introduce typedef again. :-P. > + > typedef struct fs_quota_stat { > __s8 qs_version; /* version number for future changes */ > + __u8 qs_pad1; /* unused */ > __u16 qs_flags; /* FS_QUOTA_{U,P,G}DQ_{ACCT,ENFD} */ > - __s8 qs_pad; /* unused */ > + __u8 qs_pad2[4]; /* unused */ > fs_qfilestat_t qs_uquota; /* user quota storage information */ > fs_qfilestat_t qs_gquota; /* group quota storage information */ > -#define qs_pquota qs_gquota > __u32 qs_incoredqs; /* number of dquots incore */ ... > __s32 qs_btimelimit; /* limit for blks timer */ > __s32 qs_itimelimit; /* limit for inodes timer */ > __s32 qs_rtbtimelimit;/* limit for rt blks timer */ Found trailing whitespace for above three lines when applying this patch. > __u16 qs_bwarnlimit; /* limit for num warnings */ > __u16 qs_iwarnlimit; /* limit for num warnings */ > + __u8 qs_pad3[4]; /* unused */ > + fs_qfilestat_t qs_pquota; /* project quota storage information */ > + /* End of Data structure for FS_QSTAT_VERSION_2 */ > } fs_quota_stat_t; > > +/* > + * Since Version 1 did not have padding at appropriate places, > + * a new data structure has been defined for the older version to > + * provide backward compatibility. > + * Future extentions of this data structure won't require new > + * data structure definitions as the current one can be extended > + * with the logic and padding in place now. > + */ > +#define FS_QSTAT_V1_SIZE (sizeof(struct fs_quota_stat_v1)) > +#define FS_QSTAT_V2_SIZE (offsetof(struct fs_quota_stat, qs_pquota) + \ > + sizeof(fs_qfilestat_t)) > + > #endif /* _LINUX_DQBLK_XFS_H */ > Thanks, -Jeff _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs