Staging: Pohmelfs: Added IO permissions and priorities.
Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/Documentation/filesystems/pohmelfs/design_notes.txt b/Documentation/filesystems/pohmelfs/design_notes.txt
index 6d6db60..dcf8335 100644
--- a/Documentation/filesystems/pohmelfs/design_notes.txt
+++ b/Documentation/filesystems/pohmelfs/design_notes.txt
@@ -56,9 +56,10 @@
data transfers.
POHMELFS clients operate with a working set of servers and are capable of balancing read-only
-operations (like lookups or directory listings) between them.
+operations (like lookups or directory listings) between them according to IO priorities.
Administrators can add or remove servers from the set at run-time via special commands (described
-in Documentation/pohmelfs/info.txt file). Writes are replicated to all servers.
+in Documentation/pohmelfs/info.txt file). Writes are replicated to all servers, which are connected
+with write permission turned on. IO priority and permissions can be changed in run-time.
POHMELFS is capable of full data channel encryption and/or strong crypto hashing.
One can select any kernel supported cipher, encryption mode, hash type and operation mode
diff --git a/Documentation/filesystems/pohmelfs/info.txt b/Documentation/filesystems/pohmelfs/info.txt
index 4e3d501..db2e413 100644
--- a/Documentation/filesystems/pohmelfs/info.txt
+++ b/Documentation/filesystems/pohmelfs/info.txt
@@ -1,6 +1,8 @@
POHMELFS usage information.
-Mount options:
+Mount options.
+All but index, number of crypto threads and maximum IO size can changed via remount.
+
idx=%u
Each mountpoint is associated with a special index via this option.
Administrator can add or remove servers from the given index, so all mounts,
@@ -52,16 +54,27 @@
Usage examples.
-Add (or remove if it already exists) server server1.net:1025 into the working set with index $idx
+Add server server1.net:1025 into the working set with index $idx
with appropriate hash algorithm and key file and cipher algorithm, mode and key file:
-$cfg -a server1.net -p 1025 -i $idx -K $hash_key -k $cipher_key
+$cfg A add -a server1.net -p 1025 -i $idx -K $hash_key -k $cipher_key
Mount filesystem with given index $idx to /mnt mountpoint.
Client will connect to all servers specified in the working set via previous command:
mount -t pohmel -o idx=$idx q /mnt
-One can add or remove servers from working set after mounting too.
+Change permissions to read-only (-I 1 option, '-I 2' - write-only, 3 - rw):
+$cfg A modify -a server1.net -p 1025 -i $idx -I 1
+Change IO priority to 123 (node with the highest priority gets read requests).
+$cfg A modify -a server1.net -p 1025 -i $idx -P 123
+
+One can check currect status of all connections in the mountstats file:
+# cat /proc/$PID/mountstats
+...
+device none mounted on /mnt with fstype pohmel
+idx addr(:port) socket_type protocol active priority permissions
+0 server1.net:1026 1 6 1 250 1
+0 server2.net:1025 1 6 1 123 3
Server installation.
diff --git a/drivers/staging/pohmelfs/config.c b/drivers/staging/pohmelfs/config.c
index 3e67da9..a6eaa42 100644
--- a/drivers/staging/pohmelfs/config.c
+++ b/drivers/staging/pohmelfs/config.c
@@ -81,6 +81,45 @@
return g;
}
+static inline void pohmelfs_insert_config_entry(struct pohmelfs_sb *psb, struct pohmelfs_config *dst)
+{
+ struct pohmelfs_config *tmp;
+
+ INIT_LIST_HEAD(&dst->config_entry);
+
+ list_for_each_entry(tmp, &psb->state_list, config_entry) {
+ if (dst->state.ctl.prio > tmp->state.ctl.prio)
+ list_add_tail(&dst->config_entry, &tmp->config_entry);
+ }
+ if (list_empty(&dst->config_entry))
+ list_add_tail(&dst->config_entry, &psb->state_list);
+}
+
+static int pohmelfs_move_config_entry(struct pohmelfs_sb *psb,
+ struct pohmelfs_config *dst, struct pohmelfs_config *new)
+{
+ if ((dst->state.ctl.prio == new->state.ctl.prio) &&
+ (dst->state.ctl.perm == new->state.ctl.perm))
+ return 0;
+
+ dprintk("%s: dst: prio: %d, perm: %x, new: prio: %d, perm: %d.\n",
+ __func__, dst->state.ctl.prio, dst->state.ctl.perm,
+ new->state.ctl.prio, new->state.ctl.perm);
+ dst->state.ctl.prio = new->state.ctl.prio;
+ dst->state.ctl.perm = new->state.ctl.perm;
+
+ list_del_init(&dst->config_entry);
+ pohmelfs_insert_config_entry(psb, dst);
+ return 0;
+}
+
+/*
+ * pohmelfs_copy_config() is used to copy new state configs from the
+ * config group (controlled by the netlink messages) into the superblock.
+ * This happens either at startup time where no transactions can access
+ * the list of the configs (and thus list of the network states), or at
+ * run-time, where it is protected by the psb->state_lock.
+ */
int pohmelfs_copy_config(struct pohmelfs_sb *psb)
{
struct pohmelfs_config_group *g;
@@ -103,7 +142,9 @@
err = 0;
list_for_each_entry(dst, &psb->state_list, config_entry) {
if (pohmelfs_config_eql(&dst->state.ctl, &c->state.ctl)) {
- err = -EEXIST;
+ err = pohmelfs_move_config_entry(psb, dst, c);
+ if (!err)
+ err = -EEXIST;
break;
}
}
@@ -119,7 +160,7 @@
memcpy(&dst->state.ctl, &c->state.ctl, sizeof(struct pohmelfs_ctl));
- list_add_tail(&dst->config_entry, &psb->state_list);
+ pohmelfs_insert_config_entry(psb, dst);
err = pohmelfs_state_init_one(psb, dst);
if (err) {
@@ -248,6 +289,13 @@
return err;
}
+static int pohmelfs_modify_config(struct pohmelfs_ctl *old, struct pohmelfs_ctl *new)
+{
+ old->perm = new->perm;
+ old->prio = new->prio;
+ return 0;
+}
+
static int pohmelfs_cn_ctl(struct cn_msg *msg, int action)
{
struct pohmelfs_config_group *g;
@@ -278,6 +326,9 @@
g->num_entry--;
kfree(c);
goto out_unlock;
+ } else if (action == POHMELFS_FLAGS_MODIFY) {
+ err = pohmelfs_modify_config(sc, ctl);
+ goto out_unlock;
} else {
err = -EEXIST;
goto out_unlock;
@@ -296,6 +347,7 @@
}
memcpy(&c->state.ctl, ctl, sizeof(struct pohmelfs_ctl));
g->num_entry++;
+
list_add_tail(&c->config_entry, &g->config_list);
out_unlock:
@@ -401,10 +453,9 @@
switch (msg->flags) {
case POHMELFS_FLAGS_ADD:
- err = pohmelfs_cn_ctl(msg, POHMELFS_FLAGS_ADD);
- break;
case POHMELFS_FLAGS_DEL:
- err = pohmelfs_cn_ctl(msg, POHMELFS_FLAGS_DEL);
+ case POHMELFS_FLAGS_MODIFY:
+ err = pohmelfs_cn_ctl(msg, msg->flags);
break;
case POHMELFS_FLAGS_SHOW:
err = pohmelfs_cn_disp(msg);
diff --git a/drivers/staging/pohmelfs/netfs.h b/drivers/staging/pohmelfs/netfs.h
index 7700e2b..c78cfcb 100644
--- a/drivers/staging/pohmelfs/netfs.h
+++ b/drivers/staging/pohmelfs/netfs.h
@@ -87,6 +87,7 @@
POHMELFS_FLAGS_DEL, /* Network state control message for DEL */
POHMELFS_FLAGS_SHOW, /* Network state control message for SHOW */
POHMELFS_FLAGS_CRYPTO, /* Crypto data control message */
+ POHMELFS_FLAGS_MODIFY, /* Network state modification message */
};
/*
diff --git a/drivers/staging/pohmelfs/trans.c b/drivers/staging/pohmelfs/trans.c
index b89f9f3..168fc89 100644
--- a/drivers/staging/pohmelfs/trans.c
+++ b/drivers/staging/pohmelfs/trans.c
@@ -456,34 +456,22 @@
__func__, t, t->gen, t->iovec.iov_len, t->page_num, psb->active_state);
#endif
mutex_lock(&psb->state_lock);
-
- if ((t->flags & NETFS_TRANS_SINGLE_DST) && psb->active_state) {
- st = &psb->active_state->state;
-
- err = -EPIPE;
- if (netfs_state_poll(st) & POLLOUT) {
- err = netfs_trans_push_dst(t, st);
- if (!err) {
- err = netfs_trans_send(t, st);
- if (err) {
- netfs_trans_drop_last(t, st);
- } else {
- pohmelfs_switch_active(psb);
- goto out;
- }
- }
- }
- pohmelfs_switch_active(psb);
- }
-
list_for_each_entry(c, &psb->state_list, config_entry) {
st = &c->state;
+ if (t->flags & NETFS_TRANS_SINGLE_DST) {
+ if (!(st->ctl.perm & POHMELFS_IO_PERM_READ))
+ continue;
+ } else {
+ if (!(st->ctl.perm & POHMELFS_IO_PERM_WRITE))
+ continue;
+ }
+
err = netfs_trans_push(t, st);
if (!err && (t->flags & NETFS_TRANS_SINGLE_DST))
break;
}
-out:
+
mutex_unlock(&psb->state_lock);
#if 0
dprintk("%s: fully sent t: %p, gen: %u, size: %u, page_num: %u, err: %d.\n",
