Message ID | 20191106091537.32480-2-s.hauer@pengutronix.de (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | Add quota support to UBIFS | expand |
On Wed 06-11-19 10:15:31, Sascha Hauer wrote: > This patch introduces the Q_PATH flag to the quotactl cmd argument. > When given, the path given in the special argument to quotactl will > be the mount path where the filesystem is mounted, instead of a path > to the block device. > This is necessary for filesystems which do not have a block device as > backing store. Particularly this is done for upcoming UBIFS support. > > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> It seems you forgot to implement changes I've asked for in [1]? [1] https://lore.kernel.org/linux-fsdevel/20191101160706.GA23441@quack2.suse.cz Honza > --- > fs/quota/quota.c | 37 ++++++++++++++++++++++++++++--------- > include/uapi/linux/quota.h | 1 + > 2 files changed, 29 insertions(+), 9 deletions(-) > > diff --git a/fs/quota/quota.c b/fs/quota/quota.c > index cb13fb76dbee..035cdd1b022b 100644 > --- a/fs/quota/quota.c > +++ b/fs/quota/quota.c > @@ -19,6 +19,7 @@ > #include <linux/types.h> > #include <linux/writeback.h> > #include <linux/nospec.h> > +#include <linux/mount.h> > > static int check_quotactl_permission(struct super_block *sb, int type, int cmd, > qid_t id) > @@ -825,12 +826,16 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, > { > uint cmds, type; > struct super_block *sb = NULL; > - struct path path, *pathp = NULL; > + struct path path, *pathp = NULL, qpath; > int ret; > + bool q_path; > > cmds = cmd >> SUBCMDSHIFT; > type = cmd & SUBCMDMASK; > > + q_path = cmds & Q_PATH; > + cmds &= ~Q_PATH; > + > /* > * As a special case Q_SYNC can be called without a specific device. > * It will iterate all superblocks that have quota enabled and call > @@ -855,19 +860,33 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, > pathp = &path; > } > > - sb = quotactl_block(special, cmds); > - if (IS_ERR(sb)) { > - ret = PTR_ERR(sb); > - goto out; > + if (q_path) { > + ret = user_path_at(AT_FDCWD, special, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, > + &qpath); > + if (ret) > + goto out1; > + > + sb = qpath.mnt->mnt_sb; > + } else { > + sb = quotactl_block(special, cmds); > + if (IS_ERR(sb)) { > + ret = PTR_ERR(sb); > + goto out; > + } > } > > ret = do_quotactl(sb, type, cmds, id, addr, pathp); > > - if (!quotactl_cmd_onoff(cmds)) > - drop_super(sb); > - else > - drop_super_exclusive(sb); > + if (!q_path) { > + if (!quotactl_cmd_onoff(cmds)) > + drop_super(sb); > + else > + drop_super_exclusive(sb); > + } > out: > + if (q_path) > + path_put(&qpath); > +out1: > if (pathp && !IS_ERR(pathp)) > path_put(pathp); > return ret; > diff --git a/include/uapi/linux/quota.h b/include/uapi/linux/quota.h > index f17c9636a859..e1787c0df601 100644 > --- a/include/uapi/linux/quota.h > +++ b/include/uapi/linux/quota.h > @@ -71,6 +71,7 @@ > #define Q_GETQUOTA 0x800007 /* get user quota structure */ > #define Q_SETQUOTA 0x800008 /* set user quota structure */ > #define Q_GETNEXTQUOTA 0x800009 /* get disk limits and usage >= ID */ > +#define Q_PATH 0x400000 /* quotactl special arg contains mount path */ > > /* Quota format type IDs */ > #define QFMT_VFS_OLD 1 > -- > 2.24.0.rc1 >
On Wed, Nov 06, 2019 at 11:05:15AM +0100, Jan Kara wrote: > On Wed 06-11-19 10:15:31, Sascha Hauer wrote: > > This patch introduces the Q_PATH flag to the quotactl cmd argument. > > When given, the path given in the special argument to quotactl will > > be the mount path where the filesystem is mounted, instead of a path > > to the block device. > > This is necessary for filesystems which do not have a block device as > > backing store. Particularly this is done for upcoming UBIFS support. > > > > Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> > > It seems you forgot to implement changes I've asked for in [1]? > > [1] https://lore.kernel.org/linux-fsdevel/20191101160706.GA23441@quack2.suse.cz Hm, yes. I somehow thought these were obsolet as the patch was superseeded by your changes. Apparently it's still there, so I'll send an updated version Sascha
diff --git a/fs/quota/quota.c b/fs/quota/quota.c index cb13fb76dbee..035cdd1b022b 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -19,6 +19,7 @@ #include <linux/types.h> #include <linux/writeback.h> #include <linux/nospec.h> +#include <linux/mount.h> static int check_quotactl_permission(struct super_block *sb, int type, int cmd, qid_t id) @@ -825,12 +826,16 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, { uint cmds, type; struct super_block *sb = NULL; - struct path path, *pathp = NULL; + struct path path, *pathp = NULL, qpath; int ret; + bool q_path; cmds = cmd >> SUBCMDSHIFT; type = cmd & SUBCMDMASK; + q_path = cmds & Q_PATH; + cmds &= ~Q_PATH; + /* * As a special case Q_SYNC can be called without a specific device. * It will iterate all superblocks that have quota enabled and call @@ -855,19 +860,33 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, pathp = &path; } - sb = quotactl_block(special, cmds); - if (IS_ERR(sb)) { - ret = PTR_ERR(sb); - goto out; + if (q_path) { + ret = user_path_at(AT_FDCWD, special, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, + &qpath); + if (ret) + goto out1; + + sb = qpath.mnt->mnt_sb; + } else { + sb = quotactl_block(special, cmds); + if (IS_ERR(sb)) { + ret = PTR_ERR(sb); + goto out; + } } ret = do_quotactl(sb, type, cmds, id, addr, pathp); - if (!quotactl_cmd_onoff(cmds)) - drop_super(sb); - else - drop_super_exclusive(sb); + if (!q_path) { + if (!quotactl_cmd_onoff(cmds)) + drop_super(sb); + else + drop_super_exclusive(sb); + } out: + if (q_path) + path_put(&qpath); +out1: if (pathp && !IS_ERR(pathp)) path_put(pathp); return ret; diff --git a/include/uapi/linux/quota.h b/include/uapi/linux/quota.h index f17c9636a859..e1787c0df601 100644 --- a/include/uapi/linux/quota.h +++ b/include/uapi/linux/quota.h @@ -71,6 +71,7 @@ #define Q_GETQUOTA 0x800007 /* get user quota structure */ #define Q_SETQUOTA 0x800008 /* set user quota structure */ #define Q_GETNEXTQUOTA 0x800009 /* get disk limits and usage >= ID */ +#define Q_PATH 0x400000 /* quotactl special arg contains mount path */ /* Quota format type IDs */ #define QFMT_VFS_OLD 1
This patch introduces the Q_PATH flag to the quotactl cmd argument. When given, the path given in the special argument to quotactl will be the mount path where the filesystem is mounted, instead of a path to the block device. This is necessary for filesystems which do not have a block device as backing store. Particularly this is done for upcoming UBIFS support. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> --- fs/quota/quota.c | 37 ++++++++++++++++++++++++++++--------- include/uapi/linux/quota.h | 1 + 2 files changed, 29 insertions(+), 9 deletions(-)