linux/net/sched/cls_tcindex.c

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/*
* net/sched/cls_tcindex.c Packet classifier for skb->tc_index
*
* Written 1998,1999 by Werner Almesberger, EPFL ICA
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/errno.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <net/act_api.h>
#include <net/netlink.h>
#include <net/pkt_cls.h>
/*
* Passing parameters to the root seems to be done more awkwardly than really
* necessary. At least, u32 doesn't seem to use such dirty hacks. To be
* verified. FIXME.
*/
#define PERFECT_HASH_THRESHOLD 64 /* use perfect hash if not bigger */
#define DEFAULT_HASH_SIZE 64 /* optimized for diffserv */
#define PRIV(tp) ((struct tcindex_data *) (tp)->root)
struct tcindex_filter_result {
struct tcf_exts exts;
struct tcf_result res;
};
struct tcindex_filter {
u16 key;
struct tcindex_filter_result result;
struct tcindex_filter *next;
};
struct tcindex_data {
struct tcindex_filter_result *perfect; /* perfect hash; NULL if none */
struct tcindex_filter **h; /* imperfect hash; only used if !perfect;
NULL if unused */
u16 mask; /* AND key with mask */
int shift; /* shift ANDed key to the right */
int hash; /* hash table size; 0 if undefined */
int alloc_hash; /* allocated size */
int fall_through; /* 0: only classify if explicit match */
};
static const struct tcf_ext_map tcindex_ext_map = {
.police = TCA_TCINDEX_POLICE,
.action = TCA_TCINDEX_ACT
};
static inline int
tcindex_filter_is_set(struct tcindex_filter_result *r)
{
return tcf_exts_is_predicative(&r->exts) || r->res.classid;
}
static struct tcindex_filter_result *
tcindex_lookup(struct tcindex_data *p, u16 key)
{
struct tcindex_filter *f;
if (p->perfect)
return tcindex_filter_is_set(p->perfect + key) ?
p->perfect + key : NULL;
else if (p->h) {
for (f = p->h[key % p->hash]; f; f = f->next)
if (f->key == key)
return &f->result;
}
return NULL;
}
static int tcindex_classify(struct sk_buff *skb, struct tcf_proto *tp,
struct tcf_result *res)
{
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter_result *f;
int key = (skb->tc_index & p->mask) >> p->shift;
pr_debug("tcindex_classify(skb %p,tp %p,res %p),p %p\n",
skb, tp, res, p);
f = tcindex_lookup(p, key);
if (!f) {
if (!p->fall_through)
return -1;
res->classid = TC_H_MAKE(TC_H_MAJ(tp->q->handle), key);
res->class = 0;
pr_debug("alg 0x%x\n", res->classid);
return 0;
}
*res = f->res;
pr_debug("map 0x%x\n", res->classid);
return tcf_exts_exec(skb, &f->exts, res);
}
static unsigned long tcindex_get(struct tcf_proto *tp, u32 handle)
{
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter_result *r;
pr_debug("tcindex_get(tp %p,handle 0x%08x)\n", tp, handle);
if (p->perfect && handle >= p->alloc_hash)
return 0;
r = tcindex_lookup(p, handle);
return r && tcindex_filter_is_set(r) ? (unsigned long) r : 0UL;
}
static void tcindex_put(struct tcf_proto *tp, unsigned long f)
{
pr_debug("tcindex_put(tp %p,f 0x%lx)\n", tp, f);
}
static int tcindex_init(struct tcf_proto *tp)
{
struct tcindex_data *p;
pr_debug("tcindex_init(tp %p)\n", tp);
p = kzalloc(sizeof(struct tcindex_data), GFP_KERNEL);
if (!p)
return -ENOMEM;
p->mask = 0xffff;
p->hash = DEFAULT_HASH_SIZE;
p->fall_through = 1;
tp->root = p;
return 0;
}
static int
__tcindex_delete(struct tcf_proto *tp, unsigned long arg, int lock)
{
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter_result *r = (struct tcindex_filter_result *) arg;
struct tcindex_filter *f = NULL;
pr_debug("tcindex_delete(tp %p,arg 0x%lx),p %p,f %p\n", tp, arg, p, f);
if (p->perfect) {
if (!r->res.class)
return -ENOENT;
} else {
int i;
struct tcindex_filter **walk = NULL;
for (i = 0; i < p->hash; i++)
for (walk = p->h+i; *walk; walk = &(*walk)->next)
if (&(*walk)->result == r)
goto found;
return -ENOENT;
found:
f = *walk;
if (lock)
tcf_tree_lock(tp);
*walk = f->next;
if (lock)
tcf_tree_unlock(tp);
}
tcf_unbind_filter(tp, &r->res);
tcf_exts_destroy(tp, &r->exts);
kfree(f);
return 0;
}
static int tcindex_delete(struct tcf_proto *tp, unsigned long arg)
{
return __tcindex_delete(tp, arg, 1);
}
static inline int
valid_perfect_hash(struct tcindex_data *p)
{
return p->hash > (p->mask >> p->shift);
}
static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
[TCA_TCINDEX_HASH] = { .type = NLA_U32 },
[TCA_TCINDEX_MASK] = { .type = NLA_U16 },
[TCA_TCINDEX_SHIFT] = { .type = NLA_U32 },
[TCA_TCINDEX_FALL_THROUGH] = { .type = NLA_U32 },
[TCA_TCINDEX_CLASSID] = { .type = NLA_U32 },
};
static int
tcindex_set_parms(struct tcf_proto *tp, unsigned long base, u32 handle,
struct tcindex_data *p, struct tcindex_filter_result *r,
struct nlattr **tb, struct nlattr *est)
{
int err, balloc = 0;
struct tcindex_filter_result new_filter_result, *old_r = r;
struct tcindex_filter_result cr;
struct tcindex_data cp;
struct tcindex_filter *f = NULL; /* make gcc behave */
struct tcf_exts e;
err = tcf_exts_validate(tp, tb, est, &e, &tcindex_ext_map);
if (err < 0)
return err;
memcpy(&cp, p, sizeof(cp));
memset(&new_filter_result, 0, sizeof(new_filter_result));
if (old_r)
memcpy(&cr, r, sizeof(cr));
else
memset(&cr, 0, sizeof(cr));
if (tb[TCA_TCINDEX_HASH])
cp.hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
if (tb[TCA_TCINDEX_MASK])
cp.mask = nla_get_u16(tb[TCA_TCINDEX_MASK]);
if (tb[TCA_TCINDEX_SHIFT])
cp.shift = nla_get_u32(tb[TCA_TCINDEX_SHIFT]);
err = -EBUSY;
/* Hash already allocated, make sure that we still meet the
* requirements for the allocated hash.
*/
if (cp.perfect) {
if (!valid_perfect_hash(&cp) ||
cp.hash > cp.alloc_hash)
goto errout;
} else if (cp.h && cp.hash != cp.alloc_hash)
goto errout;
err = -EINVAL;
if (tb[TCA_TCINDEX_FALL_THROUGH])
cp.fall_through = nla_get_u32(tb[TCA_TCINDEX_FALL_THROUGH]);
if (!cp.hash) {
/* Hash not specified, use perfect hash if the upper limit
* of the hashing index is below the threshold.
*/
if ((cp.mask >> cp.shift) < PERFECT_HASH_THRESHOLD)
cp.hash = (cp.mask >> cp.shift) + 1;
else
cp.hash = DEFAULT_HASH_SIZE;
}
if (!cp.perfect && !cp.h)
cp.alloc_hash = cp.hash;
/* Note: this could be as restrictive as if (handle & ~(mask >> shift))
* but then, we'd fail handles that may become valid after some future
* mask change. While this is extremely unlikely to ever matter,
* the check below is safer (and also more backwards-compatible).
*/
if (cp.perfect || valid_perfect_hash(&cp))
if (handle >= cp.alloc_hash)
goto errout;
err = -ENOMEM;
if (!cp.perfect && !cp.h) {
if (valid_perfect_hash(&cp)) {
cp.perfect = kcalloc(cp.hash, sizeof(*r), GFP_KERNEL);
if (!cp.perfect)
goto errout;
balloc = 1;
} else {
cp.h = kcalloc(cp.hash, sizeof(f), GFP_KERNEL);
if (!cp.h)
goto errout;
balloc = 2;
}
}
if (cp.perfect)
r = cp.perfect + handle;
else
r = tcindex_lookup(&cp, handle) ? : &new_filter_result;
if (r == &new_filter_result) {
f = kzalloc(sizeof(*f), GFP_KERNEL);
if (!f)
goto errout_alloc;
}
if (tb[TCA_TCINDEX_CLASSID]) {
cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
tcf_bind_filter(tp, &cr.res, base);
}
tcf_exts_change(tp, &cr.exts, &e);
tcf_tree_lock(tp);
if (old_r && old_r != r)
memset(old_r, 0, sizeof(*old_r));
memcpy(p, &cp, sizeof(cp));
memcpy(r, &cr, sizeof(cr));
if (r == &new_filter_result) {
struct tcindex_filter **fp;
f->key = handle;
f->result = new_filter_result;
f->next = NULL;
for (fp = p->h+(handle % p->hash); *fp; fp = &(*fp)->next)
/* nothing */;
*fp = f;
}
tcf_tree_unlock(tp);
return 0;
errout_alloc:
if (balloc == 1)
kfree(cp.perfect);
else if (balloc == 2)
kfree(cp.h);
errout:
tcf_exts_destroy(tp, &e);
return err;
}
static int
tcindex_change(struct tcf_proto *tp, unsigned long base, u32 handle,
struct nlattr **tca, unsigned long *arg)
{
struct nlattr *opt = tca[TCA_OPTIONS];
struct nlattr *tb[TCA_TCINDEX_MAX + 1];
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter_result *r = (struct tcindex_filter_result *) *arg;
int err;
pr_debug("tcindex_change(tp %p,handle 0x%08x,tca %p,arg %p),opt %p,"
"p %p,r %p,*arg 0x%lx\n",
tp, handle, tca, arg, opt, p, r, arg ? *arg : 0L);
if (!opt)
return 0;
err = nla_parse_nested(tb, TCA_TCINDEX_MAX, opt, tcindex_policy);
if (err < 0)
return err;
return tcindex_set_parms(tp, base, handle, p, r, tb, tca[TCA_RATE]);
}
static void tcindex_walk(struct tcf_proto *tp, struct tcf_walker *walker)
{
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter *f, *next;
int i;
pr_debug("tcindex_walk(tp %p,walker %p),p %p\n", tp, walker, p);
if (p->perfect) {
for (i = 0; i < p->hash; i++) {
if (!p->perfect[i].res.class)
continue;
if (walker->count >= walker->skip) {
if (walker->fn(tp,
(unsigned long) (p->perfect+i), walker)
< 0) {
walker->stop = 1;
return;
}
}
walker->count++;
}
}
if (!p->h)
return;
for (i = 0; i < p->hash; i++) {
for (f = p->h[i]; f; f = next) {
next = f->next;
if (walker->count >= walker->skip) {
if (walker->fn(tp, (unsigned long) &f->result,
walker) < 0) {
walker->stop = 1;
return;
}
}
walker->count++;
}
}
}
static int tcindex_destroy_element(struct tcf_proto *tp,
unsigned long arg, struct tcf_walker *walker)
{
return __tcindex_delete(tp, arg, 0);
}
static void tcindex_destroy(struct tcf_proto *tp)
{
struct tcindex_data *p = PRIV(tp);
struct tcf_walker walker;
pr_debug("tcindex_destroy(tp %p),p %p\n", tp, p);
walker.count = 0;
walker.skip = 0;
walker.fn = &tcindex_destroy_element;
tcindex_walk(tp, &walker);
kfree(p->perfect);
kfree(p->h);
kfree(p);
tp->root = NULL;
}
static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
struct sk_buff *skb, struct tcmsg *t)
{
struct tcindex_data *p = PRIV(tp);
struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
unsigned char *b = skb_tail_pointer(skb);
struct nlattr *nest;
pr_debug("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
tp, fh, skb, t, p, r, b);
pr_debug("p->perfect %p p->h %p\n", p->perfect, p->h);
nest = nla_nest_start(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
if (!fh) {
t->tcm_handle = ~0; /* whatever ... */
NLA_PUT_U32(skb, TCA_TCINDEX_HASH, p->hash);
NLA_PUT_U16(skb, TCA_TCINDEX_MASK, p->mask);
NLA_PUT_U32(skb, TCA_TCINDEX_SHIFT, p->shift);
NLA_PUT_U32(skb, TCA_TCINDEX_FALL_THROUGH, p->fall_through);
nla_nest_end(skb, nest);
} else {
if (p->perfect) {
t->tcm_handle = r-p->perfect;
} else {
struct tcindex_filter *f;
int i;
t->tcm_handle = 0;
for (i = 0; !t->tcm_handle && i < p->hash; i++) {
for (f = p->h[i]; !t->tcm_handle && f;
f = f->next) {
if (&f->result == r)
t->tcm_handle = f->key;
}
}
}
pr_debug("handle = %d\n", t->tcm_handle);
if (r->res.class)
NLA_PUT_U32(skb, TCA_TCINDEX_CLASSID, r->res.classid);
if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
goto nla_put_failure;
nla_nest_end(skb, nest);
if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
goto nla_put_failure;
}
return skb->len;
nla_put_failure:
nlmsg_trim(skb, b);
return -1;
}
static struct tcf_proto_ops cls_tcindex_ops __read_mostly = {
.kind = "tcindex",
.classify = tcindex_classify,
.init = tcindex_init,
.destroy = tcindex_destroy,
.get = tcindex_get,
.put = tcindex_put,
.change = tcindex_change,
.delete = tcindex_delete,
.walk = tcindex_walk,
.dump = tcindex_dump,
.owner = THIS_MODULE,
};
static int __init init_tcindex(void)
{
return register_tcf_proto_ops(&cls_tcindex_ops);
}
static void __exit exit_tcindex(void)
{
unregister_tcf_proto_ops(&cls_tcindex_ops);
}
module_init(init_tcindex)
module_exit(exit_tcindex)
MODULE_LICENSE("GPL");