quota: Keep which entries were set by SETQUOTA quotactl

Quota in a clustered environment needs to synchronize quota information
among cluster nodes. This means we have to occasionally update some
information in dquot from disk / network. On the other hand we have to
be careful not to overwrite changes administrator did via SETQUOTA.
So indicate in dquot->dq_flags which entries have been set by SETQUOTA
and quota format can clear these flags when it properly propagated
the changes.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

diff --git a/fs/dquot.c b/fs/dquot.c
index 9c78ffe1aad2e7408d92bc8460195e607e8ed0ce..89226726daa8c52656d1e1ba38a9bf4683fd66e8 100644 (file)
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -2010,25 +2010,33 @@ static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
        if (di->dqb_valid & QIF_SPACE) {
                dm->dqb_curspace = di->dqb_curspace;
                check_blim = 1;
+               __set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
        }
        if (di->dqb_valid & QIF_BLIMITS) {
                dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
                dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
                check_blim = 1;
+               __set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
        }
        if (di->dqb_valid & QIF_INODES) {
                dm->dqb_curinodes = di->dqb_curinodes;
                check_ilim = 1;
+               __set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
        }
        if (di->dqb_valid & QIF_ILIMITS) {
                dm->dqb_isoftlimit = di->dqb_isoftlimit;
                dm->dqb_ihardlimit = di->dqb_ihardlimit;
                check_ilim = 1;
+               __set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
        }
-       if (di->dqb_valid & QIF_BTIME)
+       if (di->dqb_valid & QIF_BTIME) {
                dm->dqb_btime = di->dqb_btime;
-       if (di->dqb_valid & QIF_ITIME)
+               __set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
+       }
+       if (di->dqb_valid & QIF_ITIME) {
                dm->dqb_itime = di->dqb_itime;
+               __set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
+       }
 
        if (check_blim) {
                if (!dm->dqb_bsoftlimit || dm->dqb_curspace < dm->dqb_bsoftlimit) {

diff --git a/include/linux/quota.h b/include/linux/quota.h
index 75bf761caef2f187b772b54bf8130560a95c9d42..6d98885c16daf9032d48a31a5cb36bf333d81276 100644 (file)
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -80,12 +80,21 @@
  * Quota structure used for communication with userspace via quotactl
  * Following flags are used to specify which fields are valid
  */
-#define QIF_BLIMITS    1
-#define QIF_SPACE      2
-#define QIF_ILIMITS    4
-#define QIF_INODES     8
-#define QIF_BTIME      16
-#define QIF_ITIME      32
+enum {
+       QIF_BLIMITS_B = 0,
+       QIF_SPACE_B,
+       QIF_ILIMITS_B,
+       QIF_INODES_B,
+       QIF_BTIME_B,
+       QIF_ITIME_B,
+};
+
+#define QIF_BLIMITS    (1 << QIF_BLIMITS_B)
+#define QIF_SPACE      (1 << QIF_SPACE_B)
+#define QIF_ILIMITS    (1 << QIF_ILIMITS_B)
+#define QIF_INODES     (1 << QIF_INODES_B)
+#define QIF_BTIME      (1 << QIF_BTIME_B)
+#define QIF_ITIME      (1 << QIF_ITIME_B)
 #define QIF_LIMITS     (QIF_BLIMITS | QIF_ILIMITS)
 #define QIF_USAGE      (QIF_SPACE | QIF_INODES)
 #define QIF_TIMES      (QIF_BTIME | QIF_ITIME)
@@ -242,6 +251,11 @@ extern struct dqstats dqstats;
 #define DQ_FAKE_B      3       /* no limits only usage */
 #define DQ_READ_B      4       /* dquot was read into memory */
 #define DQ_ACTIVE_B    5       /* dquot is active (dquot_release not called) */
+#define DQ_LASTSET_B   6       /* Following 6 bits (see QIF_) are reserved\
+                                * for the mask of entries set via SETQUOTA\
+                                * quotactl. They are set under dq_data_lock\
+                                * and the quota format handling dquot can\
+                                * clear them when it sees fit. */
 
 struct dquot {
        struct hlist_node dq_hash;      /* Hash list in memory */