VFS: Export dquot_send_warning

Sending a message to userspace in a generic format to warn
of events (e.g. quota exceeded) in the quota subsystem is
a generically useful feature. This patch makes some minor
changes to the send_message function from dquot.c renaming
it quota_send_message, moving it to quota.c and exporting it
for use by filesystems which do not use the dquot code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 9 insertions, 84 deletions

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 39b49c42a7ed..9b6ad908dcb2 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -77,10 +77,6 @@
 #include <linux/capability.h>
 #include <linux/quotaops.h>
 #include <linux/writeback.h> /* for inode_lock, oddly enough.. */
-#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
-#include <net/netlink.h>
-#include <net/genetlink.h>
-#endif
 
 #include <asm/uaccess.h>
 
@@ -1071,73 +1067,6 @@ static void print_warning(struct dquot *dquot, const int warntype)
 }
 #endif
 
-#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
-
-/* Netlink family structure for quota */
-static struct genl_family quota_genl_family = {
-        .id = GENL_ID_GENERATE,
-        .hdrsize = 0,
-        .name = "VFS_DQUOT",
-        .version = 1,
-        .maxattr = QUOTA_NL_A_MAX,
-};
-
-/* Send warning to userspace about user which exceeded quota */
-static void send_warning(const struct dquot *dquot, const char warntype)
-{
-        static atomic_t seq;
-        struct sk_buff *skb;
-        void *msg_head;
-        int ret;
-        int msg_size = 4 * nla_total_size(sizeof(u32)) +
-                       2 * nla_total_size(sizeof(u64));
-
-        /* We have to allocate using GFP_NOFS as we are called from a
-         * filesystem performing write and thus further recursion into
-         * the fs to free some data could cause deadlocks. */
-        skb = genlmsg_new(msg_size, GFP_NOFS);
-        if (!skb) {
-                printk(KERN_ERR
-                  "VFS: Not enough memory to send quota warning.\n");
-                return;
-        }
-        msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
-                        &quota_genl_family, 0, QUOTA_NL_C_WARNING);
-        if (!msg_head) {
-                printk(KERN_ERR
-                  "VFS: Cannot store netlink header in quota warning.\n");
-                goto err_out;
-        }
-        ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
-        if (ret)
-                goto attr_err_out;
-        ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
-        if (ret)
-                goto attr_err_out;
-        ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
-        if (ret)
-                goto attr_err_out;
-        ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
-                MAJOR(dquot->dq_sb->s_dev));
-        if (ret)
-                goto attr_err_out;
-        ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
-                MINOR(dquot->dq_sb->s_dev));
-        if (ret)
-                goto attr_err_out;
-        ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
-        if (ret)
-                goto attr_err_out;
-        genlmsg_end(skb, msg_head);
-
-        genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
-        return;
-attr_err_out:
-        printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
-err_out:
-        kfree_skb(skb);
-}
-#endif
 /*
  * Write warnings to the console and send warning messages over netlink.
  *
@@ -1145,18 +1074,20 @@ err_out:
  */
 static void flush_warnings(struct dquot *const *dquots, char *warntype)
 {
+        struct dquot *dq;
         int i;
 
-        for (i = 0; i < MAXQUOTAS; i++)
-                if (dquots[i] && warntype[i] != QUOTA_NL_NOWARN &&
-                    !warning_issued(dquots[i], warntype[i])) {
+        for (i = 0; i < MAXQUOTAS; i++) {
+                dq = dquots[i];
+                if (dq && warntype[i] != QUOTA_NL_NOWARN &&
+                    !warning_issued(dq, warntype[i])) {
 #ifdef CONFIG_PRINT_QUOTA_WARNING
-                        print_warning(dquots[i], warntype[i]);
-#endif
-#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
-                        send_warning(dquots[i], warntype[i]);
+                        print_warning(dq, warntype[i]);
 #endif
+                        quota_send_warning(dq->dq_type, dq->dq_id,
+                                           dq->dq_sb->s_dev, warntype[i]);
                 }
+        }
 }
 
 static int ignore_hardlimit(struct dquot *dquot)
@@ -2607,12 +2538,6 @@ static int __init dquot_init(void)
 
         register_shrinker(&dqcache_shrinker);
 
-#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
-        if (genl_register_family(&quota_genl_family) != 0)
-                printk(KERN_ERR
-                       "VFS: Failed to create quota netlink interface.\n");
-#endif
-
         return 0;
 }
 module_init(dquot_init);