[src/trunk]: src/sys/ufs/ufs Teach quota2 QUOTACTL_GETALL to start in the mid...

[dholland <dholland%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c659386748c8
branches:  trunk
changeset: 773192:c659386748c8
user:      dholland <dholland%NetBSD.org@localhost>
date:      Sun Jan 29 07:03:47 2012 +0000

description:
Teach quota2 QUOTACTL_GETALL to start in the middle, step 1.

diffstat:

 sys/ufs/ufs/ufs_quota2.c |  55 +++++++++++++++++++++++++++++++++++++++++------
 1 files changed, 48 insertions(+), 7 deletions(-)

diffs (119 lines):

diff -r c223de8b1e28 -r c659386748c8 sys/ufs/ufs/ufs_quota2.c
--- a/sys/ufs/ufs/ufs_quota2.c  Sun Jan 29 07:02:06 2012 +0000
+++ b/sys/ufs/ufs/ufs_quota2.c  Sun Jan 29 07:03:47 2012 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: ufs_quota2.c,v 1.18 2012/01/29 07:02:06 dholland Exp $ */
+/* $NetBSD: ufs_quota2.c,v 1.19 2012/01/29 07:03:47 dholland Exp $ */
 /*-
   * Copyright (c) 2010 Manuel Bouyer
   * All rights reserved.
@@ -26,7 +26,7 @@
   */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ufs_quota2.c,v 1.18 2012/01/29 07:02:06 dholland Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ufs_quota2.c,v 1.19 2012/01/29 07:03:47 dholland Exp $");
 
 #include <sys/buf.h>
 #include <sys/param.h>
@@ -956,7 +956,12 @@
 }
 
 struct ufsq2_cursor {
-       uint32_t q2c_magic;
+       uint32_t q2c_magic;     /* magic number */
+       int q2c_hashsize;       /* size of hash table at last go */
+
+       int q2c_defaults_done;  /* true if we've returned the default values */
+       int q2c_hashpos;        /* slot to start at in hash table */
+       int q2c_blocks_done;    /* true if we've returned the blocks value */
 };
 
 #define Q2C_MAGIC (0xbeebe111)
@@ -1010,6 +1015,7 @@
        const int needswap = UFS_MPNEEDSWAP(ump);
        struct getuids gu;
        id_t junkid;
+       struct quotaval qv;
        unsigned num, maxnum;
 
        cursor = Q2CURSOR(qkc);
@@ -1026,9 +1032,21 @@
                mutex_exit(&dqlock);
                return error;
        }
-       quota2_ufs_rwq2e(&q2h->q2h_defentry, &q2e, needswap);
-       q2e_to_quotaval(&q2e, 1, &junkid, QL_BLOCK, &result->qr_defblocks);
-       q2e_to_quotaval(&q2e, 1, &junkid, QL_FILE, &result->qr_deffiles);
+
+       if (cursor->q2c_defaults_done == 0) {
+               quota2_ufs_rwq2e(&q2h->q2h_defentry, &q2e, needswap);
+               if (cursor->q2c_blocks_done == 0) {
+                       q2e_to_quotaval(&q2e, 1, &junkid, QL_BLOCK, &qv);
+                       result->qr_defblocks = qv;
+                       cursor->q2c_blocks_done = 1;
+               }
+               if (cursor->q2c_blocks_done == 1) {
+                       q2e_to_quotaval(&q2e, 1, &junkid, QL_FILE, &qv);
+                       result->qr_deffiles = qv;
+                       cursor->q2c_blocks_done = 0;
+                       cursor->q2c_defaults_done = 1;
+               }
+       }
 
        /*
         * we can't directly get entries as we can't walk the list
@@ -1038,7 +1056,22 @@
         */
        memset(&gu, 0, sizeof(gu));
        quota2_hash_size = ufs_rw16(q2h->q2h_hash_size, needswap);
-       for (i = 0; i < quota2_hash_size ; i++) {
+
+       /* if the table size has changed, make the caller start over */
+       if (cursor->q2c_hashsize == 0) {
+               cursor->q2c_hashsize = quota2_hash_size;
+       } else if (cursor->q2c_hashsize != quota2_hash_size) {
+               error = EDEADLK;
+               goto fail;
+       }
+
+       /* why are these variables signed? */
+       if (cursor->q2c_hashpos < 0) {
+               error = EINVAL;
+               goto fail;
+       }
+
+       for (i = cursor->q2c_hashpos; i < quota2_hash_size ; i++) {
                offset = q2h->q2h_entries[i];
                error = quota2_walk_list(ump, hbp, idtype, &offset, 0, &gu,
                    quota2_getuids_callback);
@@ -1048,7 +1081,9 @@
                        break;
                }
        }
+       cursor->q2c_hashpos = i;
 
+fail:
        mutex_exit(&dqlock);
        brelse(hbp, 0);
        if (error)
@@ -1085,6 +1120,10 @@
        cursor = Q2CURSOR(qkc);
 
        cursor->q2c_magic = Q2C_MAGIC;
+       cursor->q2c_hashsize = 0;
+       cursor->q2c_hashpos = 0;
+       cursor->q2c_defaults_done = 0;
+       cursor->q2c_blocks_done = 0;
        return 0;
 }
 
@@ -1098,6 +1137,8 @@
                return EINVAL;
        }
 
+       /* nothing to do */
+
        return 0;
 }