ceph: specify max_bytes on readdir replies

Specify max bytes in request to bound size of reply.  Add associated
mount option with default value of 512 KB.

Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 8 insertions, 0 deletions

diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 7f5b20dc4945..bac13898b943 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -190,6 +190,8 @@ static int ceph_show_options(struct seq_file *m, struct vfsmount *mnt)
                            args->cap_release_safety);
         if (args->max_readdir != CEPH_MAX_READDIR_DEFAULT)
                 seq_printf(m, ",readdir_max_entries=%d", args->max_readdir);
+        if (args->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
+                seq_printf(m, ",readdir_max_bytes=%d", args->max_readdir_bytes);
         if (strcmp(args->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
                 seq_printf(m, ",snapdirname=%s", args->snapdir_name);
         if (args->name)
@@ -333,6 +335,7 @@ enum {
         Opt_caps_wanted_delay_max,
         Opt_cap_release_safety,
         Opt_readdir_max_entries,
+        Opt_readdir_max_bytes,
         Opt_congestion_kb,
         Opt_last_int,
         /* int args above */
@@ -365,6 +368,7 @@ static match_table_t arg_tokens = {
         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
         {Opt_cap_release_safety, "cap_release_safety=%d"},
         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
+        {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
         {Opt_congestion_kb, "write_congestion_kb=%d"},
         /* int args above */
         {Opt_snapdirname, "snapdirname=%s"},
@@ -415,6 +419,7 @@ static struct ceph_mount_args *parse_mount_args(int flags, char *options,
         args->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
         args->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
         args->max_readdir = CEPH_MAX_READDIR_DEFAULT;
+        args->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
         args->congestion_kb = default_congestion_kb();
 
         /* ip1[:port1][,ip2[:port2]...]:/subdir/in/fs */
@@ -522,6 +527,9 @@ static struct ceph_mount_args *parse_mount_args(int flags, char *options,
                 case Opt_readdir_max_entries:
                         args->max_readdir = intval;
                         break;
+                case Opt_readdir_max_bytes:
+                        args->max_readdir_bytes = intval;
+                        break;
                 case Opt_congestion_kb:
                         args->congestion_kb = intval;
                         break;