diff options
| -rw-r--r-- | include/net/sctp/command.h | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h index 589a1918ad55..f22538e68245 100644 --- a/include/net/sctp/command.h +++ b/include/net/sctp/command.h @@ -203,8 +203,8 @@ typedef struct { typedef struct { sctp_cmd_t cmds[SCTP_MAX_NUM_COMMANDS]; - __u8 next_free_slot; - __u8 next_cmd; + sctp_cmd_t *last_used_slot; + sctp_cmd_t *next_cmd; } sctp_cmd_seq_t; @@ -213,8 +213,9 @@ typedef struct { */ static inline int sctp_init_cmd_seq(sctp_cmd_seq_t *seq) { - seq->next_free_slot = 0; - seq->next_cmd = 0; + /* cmds[] is filled backwards to simplify the overflow BUG() check */ + seq->last_used_slot = seq->cmds + SCTP_MAX_NUM_COMMANDS; + seq->next_cmd = seq->last_used_slot; return 1; /* We always succeed. */ } @@ -227,10 +228,13 @@ static inline int sctp_init_cmd_seq(sctp_cmd_seq_t *seq) static inline void sctp_add_cmd_sf(sctp_cmd_seq_t *seq, sctp_verb_t verb, sctp_arg_t obj) { - BUG_ON(seq->next_free_slot >= SCTP_MAX_NUM_COMMANDS); + sctp_cmd_t *cmd = seq->last_used_slot - 1; - seq->cmds[seq->next_free_slot].verb = verb; - seq->cmds[seq->next_free_slot++].obj = obj; + BUG_ON(cmd < seq->cmds); + + cmd->verb = verb; + cmd->obj = obj; + seq->last_used_slot = cmd; } /* Return the next command structure in an sctp_cmd_seq. @@ -238,12 +242,10 @@ static inline void sctp_add_cmd_sf(sctp_cmd_seq_t *seq, sctp_verb_t verb, */ static inline sctp_cmd_t *sctp_next_cmd(sctp_cmd_seq_t *seq) { - sctp_cmd_t *retval = NULL; - - if (seq->next_cmd < seq->next_free_slot) - retval = &seq->cmds[seq->next_cmd++]; + if (seq->next_cmd <= seq->last_used_slot) + return NULL; - return retval; + return --seq->next_cmd; } #endif /* __net_sctp_command_h__ */ |