From 9b395bc3be1cebf0144a127c7e67d56dbdac0930 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 26 Oct 2012 00:36:40 +0200 Subject: mac80211: verify that skb data is present A number of places in the mesh code don't check that the frame data is present and in the skb header when trying to access. Add those checks and the necessary pskb_may_pull() calls. This prevents accessing data that doesn't actually exist. To do this, export ieee80211_get_mesh_hdrlen() to be able to use it in mac80211. Cc: stable@vger.kernel.org Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include') diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index f8cd4cf3fad..7d5b6000378 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -2651,6 +2651,15 @@ unsigned int ieee80211_get_hdrlen_from_skb(const struct sk_buff *skb); */ unsigned int __attribute_const__ ieee80211_hdrlen(__le16 fc); +/** + * ieee80211_get_mesh_hdrlen - get mesh extension header length + * @meshhdr: the mesh extension header, only the flags field + * (first byte) will be accessed + * Returns the length of the extension header, which is always at + * least 6 bytes and at most 18 if address 5 and 6 are present. + */ +unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr); + /** * DOC: Data path helpers * -- cgit v1.2.3-18-g5258 From 95a7d76897c1e7243d4137037c66d15cbf2cce76 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Wed, 31 Oct 2012 12:38:31 -0400 Subject: xen/mmu: Use Xen specific TLB flush instead of the generic one. As Mukesh explained it, the MMUEXT_TLB_FLUSH_ALL allows the hypervisor to do a TLB flush on all active vCPUs. If instead we were using the generic one (which ends up being xen_flush_tlb) we end up making the MMUEXT_TLB_FLUSH_LOCAL hypercall. But before we make that hypercall the kernel will IPI all of the vCPUs (even those that were asleep from the hypervisor perspective). The end result is that we needlessly wake them up and do a TLB flush when we can just let the hypervisor do it correctly. This patch gives around 50% speed improvement when migrating idle guest's from one host to another. Oracle-bug: 14630170 CC: stable@vger.kernel.org Tested-by: Jingjie Jiang Suggested-by: Mukesh Rathor Signed-off-by: Konrad Rzeszutek Wilk --- include/trace/events/xen.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include') diff --git a/include/trace/events/xen.h b/include/trace/events/xen.h index 15ba03bdd7c..d06b6da5c1e 100644 --- a/include/trace/events/xen.h +++ b/include/trace/events/xen.h @@ -377,6 +377,14 @@ DECLARE_EVENT_CLASS(xen_mmu_pgd, DEFINE_XEN_MMU_PGD_EVENT(xen_mmu_pgd_pin); DEFINE_XEN_MMU_PGD_EVENT(xen_mmu_pgd_unpin); +TRACE_EVENT(xen_mmu_flush_tlb_all, + TP_PROTO(int x), + TP_ARGS(x), + TP_STRUCT__entry(__array(char, x, 0)), + TP_fast_assign((void)x), + TP_printk("%s", "") + ); + TRACE_EVENT(xen_mmu_flush_tlb, TP_PROTO(int x), TP_ARGS(x), -- cgit v1.2.3-18-g5258 From d9b482c8ba1973a189f2d4c8175d405b87fbf2d7 Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Tue, 30 Oct 2012 14:45:57 -0400 Subject: hashtable: introduce a small and naive hashtable This hashtable implementation is using hlist buckets to provide a simple hashtable to prevent it from getting reimplemented all over the kernel. Signed-off-by: Sasha Levin [ Merging this now, so that subsystems can start applying Sasha's patches that use this - Linus ] Signed-off-by: Linus Torvalds --- include/linux/hashtable.h | 192 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 192 insertions(+) create mode 100644 include/linux/hashtable.h (limited to 'include') diff --git a/include/linux/hashtable.h b/include/linux/hashtable.h new file mode 100644 index 00000000000..227c62424f3 --- /dev/null +++ b/include/linux/hashtable.h @@ -0,0 +1,192 @@ +/* + * Statically sized hash table implementation + * (C) 2012 Sasha Levin + */ + +#ifndef _LINUX_HASHTABLE_H +#define _LINUX_HASHTABLE_H + +#include +#include +#include +#include +#include + +#define DEFINE_HASHTABLE(name, bits) \ + struct hlist_head name[1 << (bits)] = \ + { [0 ... ((1 << (bits)) - 1)] = HLIST_HEAD_INIT } + +#define DECLARE_HASHTABLE(name, bits) \ + struct hlist_head name[1 << (bits)] + +#define HASH_SIZE(name) (ARRAY_SIZE(name)) +#define HASH_BITS(name) ilog2(HASH_SIZE(name)) + +/* Use hash_32 when possible to allow for fast 32bit hashing in 64bit kernels. */ +#define hash_min(val, bits) \ + (sizeof(val) <= 4 ? hash_32(val, bits) : hash_long(val, bits)) + +static inline void __hash_init(struct hlist_head *ht, unsigned int sz) +{ + unsigned int i; + + for (i = 0; i < sz; i++) + INIT_HLIST_HEAD(&ht[i]); +} + +/** + * hash_init - initialize a hash table + * @hashtable: hashtable to be initialized + * + * Calculates the size of the hashtable from the given parameter, otherwise + * same as hash_init_size. + * + * This has to be a macro since HASH_BITS() will not work on pointers since + * it calculates the size during preprocessing. + */ +#define hash_init(hashtable) __hash_init(hashtable, HASH_SIZE(hashtable)) + +/** + * hash_add - add an object to a hashtable + * @hashtable: hashtable to add to + * @node: the &struct hlist_node of the object to be added + * @key: the key of the object to be added + */ +#define hash_add(hashtable, node, key) \ + hlist_add_head(node, &hashtable[hash_min(key, HASH_BITS(hashtable))]) + +/** + * hash_add_rcu - add an object to a rcu enabled hashtable + * @hashtable: hashtable to add to + * @node: the &struct hlist_node of the object to be added + * @key: the key of the object to be added + */ +#define hash_add_rcu(hashtable, node, key) \ + hlist_add_head_rcu(node, &hashtable[hash_min(key, HASH_BITS(hashtable))]) + +/** + * hash_hashed - check whether an object is in any hashtable + * @node: the &struct hlist_node of the object to be checked + */ +static inline bool hash_hashed(struct hlist_node *node) +{ + return !hlist_unhashed(node); +} + +static inline bool __hash_empty(struct hlist_head *ht, unsigned int sz) +{ + unsigned int i; + + for (i = 0; i < sz; i++) + if (!hlist_empty(&ht[i])) + return false; + + return true; +} + +/** + * hash_empty - check whether a hashtable is empty + * @hashtable: hashtable to check + * + * This has to be a macro since HASH_BITS() will not work on pointers since + * it calculates the size during preprocessing. + */ +#define hash_empty(hashtable) __hash_empty(hashtable, HASH_SIZE(hashtable)) + +/** + * hash_del - remove an object from a hashtable + * @node: &struct hlist_node of the object to remove + */ +static inline void hash_del(struct hlist_node *node) +{ + hlist_del_init(node); +} + +/** + * hash_del_rcu - remove an object from a rcu enabled hashtable + * @node: &struct hlist_node of the object to remove + */ +static inline void hash_del_rcu(struct hlist_node *node) +{ + hlist_del_init_rcu(node); +} + +/** + * hash_for_each - iterate over a hashtable + * @name: hashtable to iterate + * @bkt: integer to use as bucket loop cursor + * @node: the &struct list_head to use as a loop cursor for each entry + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + */ +#define hash_for_each(name, bkt, node, obj, member) \ + for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\ + hlist_for_each_entry(obj, node, &name[bkt], member) + +/** + * hash_for_each_rcu - iterate over a rcu enabled hashtable + * @name: hashtable to iterate + * @bkt: integer to use as bucket loop cursor + * @node: the &struct list_head to use as a loop cursor for each entry + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + */ +#define hash_for_each_rcu(name, bkt, node, obj, member) \ + for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\ + hlist_for_each_entry_rcu(obj, node, &name[bkt], member) + +/** + * hash_for_each_safe - iterate over a hashtable safe against removal of + * hash entry + * @name: hashtable to iterate + * @bkt: integer to use as bucket loop cursor + * @node: the &struct list_head to use as a loop cursor for each entry + * @tmp: a &struct used for temporary storage + * @obj: the type * to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + */ +#define hash_for_each_safe(name, bkt, node, tmp, obj, member) \ + for ((bkt) = 0, node = NULL; node == NULL && (bkt) < HASH_SIZE(name); (bkt)++)\ + hlist_for_each_entry_safe(obj, node, tmp, &name[bkt], member) + +/** + * hash_for_each_possible - iterate over all possible objects hashing to the + * same bucket + * @name: hashtable to iterate + * @obj: the type * to use as a loop cursor for each entry + * @node: the &struct list_head to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + * @key: the key of the objects to iterate over + */ +#define hash_for_each_possible(name, obj, node, member, key) \ + hlist_for_each_entry(obj, node, &name[hash_min(key, HASH_BITS(name))], member) + +/** + * hash_for_each_possible_rcu - iterate over all possible objects hashing to the + * same bucket in an rcu enabled hashtable + * in a rcu enabled hashtable + * @name: hashtable to iterate + * @obj: the type * to use as a loop cursor for each entry + * @node: the &struct list_head to use as a loop cursor for each entry + * @member: the name of the hlist_node within the struct + * @key: the key of the objects to iterate over + */ +#define hash_for_each_possible_rcu(name, obj, node, member, key) \ + hlist_for_each_entry_rcu(obj, node, &name[hash_min(key, HASH_BITS(name))], member) + +/** + * hash_for_each_possible_safe - iterate over all possible objects hashing to the + * same bucket safe against removals + * @name: hashtable to iterate + * @obj: the type * to use as a loop cursor for each entry + * @node: the &struct list_head to use as a loop cursor for each entry + * @tmp: a &struct used for temporary storage + * @member: the name of the hlist_node within the struct + * @key: the key of the objects to iterate over + */ +#define hash_for_each_possible_safe(name, obj, node, tmp, member, key) \ + hlist_for_each_entry_safe(obj, node, tmp, \ + &name[hash_min(key, HASH_BITS(name))], member) + + +#endif -- cgit v1.2.3-18-g5258