From 883ca833e5fb814fb03426c9d35e5489ce43e8da Mon Sep 17 00:00:00 2001 From: Gerrit Renker Date: Fri, 16 Jan 2009 23:36:32 +0000 Subject: dccp: Initialisation and type-checking of feature sysctls This patch takes care of initialising and type-checking sysctls related to feature negotiation. Type checking is important since some of the sysctls now directly impact the feature-negotiation process. The sysctls are initialised with the known default values for each feature. For the type-checking the value constraints from RFC 4340 are used: * Sequence Window uses the specified Wmin=32, the maximum is ulong (4 bytes), tested and confirmed that it works up to 4294967295 - for Gbps speed; * Ack Ratio is between 0 .. 0xffff (2-byte unsigned integer); * CCIDs are between 0 .. 255; * request_retries, retries1, retries2 also between 0..255 for good measure; * tx_qlen is checked to be non-negative; * sync_ratelimit remains as before. Notes: ------ 1. Die s@sysctl_dccp_feat@sysctl_dccp@g since the sysctls are now in feat.c. 2. As pointed out by Arnaldo, the pattern of type-checking repeats itself in other places, sometimes with exactly the same kind of definitions (e.g. "static int zero;"). It may be a good idea (kernel janitors?) to consolidate type checking. For the sake of keeping the changeset small and in order not to affect other subsystems, I have not strived to generalise here. Signed-off-by: Gerrit Renker Acked-by: Ian McDonald Signed-off-by: David S. Miller --- net/dccp/sysctl.c | 43 ++++++++++++++++++++++++++++++------------- 1 file changed, 30 insertions(+), 13 deletions(-) (limited to 'net/dccp/sysctl.c') diff --git a/net/dccp/sysctl.c b/net/dccp/sysctl.c index 018e210..a5a1856 100644 --- a/net/dccp/sysctl.c +++ b/net/dccp/sysctl.c @@ -18,55 +18,72 @@ #error This file should not be compiled without CONFIG_SYSCTL defined #endif +/* Boundary values */ +static int zero = 0, + u8_max = 0xFF; +static unsigned long seqw_min = 32; + static struct ctl_table dccp_default_table[] = { { .procname = "seq_window", - .data = &sysctl_dccp_feat_sequence_window, - .maxlen = sizeof(sysctl_dccp_feat_sequence_window), + .data = &sysctl_dccp_sequence_window, + .maxlen = sizeof(sysctl_dccp_sequence_window), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_doulongvec_minmax, + .extra1 = &seqw_min, /* RFC 4340, 7.5.2 */ }, { .procname = "rx_ccid", - .data = &sysctl_dccp_feat_rx_ccid, - .maxlen = sizeof(sysctl_dccp_feat_rx_ccid), + .data = &sysctl_dccp_rx_ccid, + .maxlen = sizeof(sysctl_dccp_rx_ccid), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, /* RFC 4340, 10. */ }, { .procname = "tx_ccid", - .data = &sysctl_dccp_feat_tx_ccid, - .maxlen = sizeof(sysctl_dccp_feat_tx_ccid), + .data = &sysctl_dccp_tx_ccid, + .maxlen = sizeof(sysctl_dccp_tx_ccid), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, /* RFC 4340, 10. */ }, { .procname = "request_retries", .data = &sysctl_dccp_request_retries, .maxlen = sizeof(sysctl_dccp_request_retries), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, }, { .procname = "retries1", .data = &sysctl_dccp_retries1, .maxlen = sizeof(sysctl_dccp_retries1), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, }, { .procname = "retries2", .data = &sysctl_dccp_retries2, .maxlen = sizeof(sysctl_dccp_retries2), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &u8_max, }, { .procname = "tx_qlen", .data = &sysctl_dccp_tx_qlen, .maxlen = sizeof(sysctl_dccp_tx_qlen), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, }, { .procname = "sync_ratelimit", -- cgit v1.1