drbd: Get rid of P_MAX_CMD

Instead of artificially enlarging the command decoding arrays to
P_MAX_CMD entries, check if an index is within the valid range using the
ARRAY_SIZE() macro.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

3 files changed, 5 insertions, 9 deletions

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 17e905d0582d..be52b58a97d7 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -225,7 +225,6 @@ enum drbd_packet {
         P_CONN_ST_CHG_REPLY   = 0x2b, /* meta sock: Connection side state req reply */
         P_RETRY_WRITE         = 0x2c, /* Protocol C: retry conflicting write request */
 
-        P_MAX_CMD             = 0x2d,
         P_MAY_IGNORE          = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */
         P_MAX_OPT_CMD         = 0x101,
 
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index b93c5eccd73d..f43752fb5b52 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -3019,7 +3019,6 @@ const char *cmdname(enum drbd_packet cmd)
                 [P_DELAY_PROBE]         = "DelayProbe",
                 [P_OUT_OF_SYNC]         = "OutOfSync",
                 [P_RETRY_WRITE]         = "RetryWrite",
-                [P_MAX_CMD]             = NULL,
         };
 
         if (cmd == P_HAND_SHAKE_M)
@@ -3028,7 +3027,7 @@ const char *cmdname(enum drbd_packet cmd)
                 return "HandShakeS";
         if (cmd == P_HAND_SHAKE)
                 return "HandShake";
-        if (cmd >= P_MAX_CMD)
+        if (cmd >= ARRAY_SIZE(cmdnames))
                 return "Unknown";
         return cmdnames[cmd];
 }
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 8c82d8945cf6..262e5d97991c 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -3875,9 +3875,6 @@ static struct data_cmd drbd_cmd_handler[] = {
         [P_DELAY_PROBE]     = { 0, sizeof(struct p_delay_probe93), receive_skip },
         [P_OUT_OF_SYNC]     = { 0, sizeof(struct p_block_desc), receive_out_of_sync },
         [P_CONN_ST_CHG_REQ] = { 0, sizeof(struct p_req_state), receive_req_state },
-        /* anything missing from this table is in
-         * the asender_tbl, see get_asender_cmd */
-        [P_MAX_CMD]         = { 0, 0, NULL },
 };
 
 /* All handler functions that expect a sub-header get that sub-heder in
@@ -3899,7 +3896,8 @@ static void drbdd(struct drbd_tconn *tconn)
                 if (!drbd_recv_header(tconn, &pi))
                         goto err_out;
 
-                if (unlikely(pi.cmd >= P_MAX_CMD || !drbd_cmd_handler[pi.cmd].function)) {
+                if (unlikely(pi.cmd >= ARRAY_SIZE(drbd_cmd_handler) ||
+                    !drbd_cmd_handler[pi.cmd].function)) {
                         conn_err(tconn, "unknown packet type %d, l: %d!\n", pi.cmd, pi.size);
                         goto err_out;
                 }
@@ -4678,9 +4676,9 @@ static struct asender_cmd *get_asender_cmd(int cmd)
         [P_RS_CANCEL]       = { sizeof(struct p_block_ack), got_NegRSDReply},
         [P_CONN_ST_CHG_REPLY]={ sizeof(struct p_req_state_reply), got_RqSReply },
         [P_RETRY_WRITE]     = { sizeof(struct p_block_ack), got_BlockAck },
-        [P_MAX_CMD]         = { 0, NULL },
         };
-        if (cmd > P_MAX_CMD || asender_tbl[cmd].process == NULL)
+
+        if (cmd >= ARRAY_SIZE(asender_tbl) || !asender_tbl[cmd].process)
                 return NULL;
         return &asender_tbl[cmd];
 }