diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Makefile | 3 | ||||
| -rw-r--r-- | lib/iommu-common.c | 6 | ||||
| -rw-r--r-- | lib/once.c | 62 | ||||
| -rw-r--r-- | lib/random32.c | 37 | ||||
| -rw-r--r-- | lib/rhashtable.c | 5 | ||||
| -rw-r--r-- | lib/string_helpers.c | 6 |
6 files changed, 94 insertions, 25 deletions
diff --git a/lib/Makefile b/lib/Makefile index 13a7c6ae3fec..8de3b012eac7 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -26,7 +26,8 @@ obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o kasprintf.o bitmap.o scatterlist.o \ gcd.o lcm.o list_sort.o uuid.o flex_array.o iov_iter.o clz_ctz.o \ bsearch.o find_bit.o llist.o memweight.o kfifo.o \ - percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o + percpu-refcount.o percpu_ida.o rhashtable.o reciprocal_div.o \ + once.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o obj-y += hexdump.o diff --git a/lib/iommu-common.c b/lib/iommu-common.c index ff19f66d3f7f..b1c93e94ca7a 100644 --- a/lib/iommu-common.c +++ b/lib/iommu-common.c @@ -21,8 +21,7 @@ static DEFINE_PER_CPU(unsigned int, iommu_hash_common); static inline bool need_flush(struct iommu_map_table *iommu) { - return (iommu->lazy_flush != NULL && - (iommu->flags & IOMMU_NEED_FLUSH) != 0); + return ((iommu->flags & IOMMU_NEED_FLUSH) != 0); } static inline void set_flush(struct iommu_map_table *iommu) @@ -211,7 +210,8 @@ unsigned long iommu_tbl_range_alloc(struct device *dev, goto bail; } } - if (n < pool->hint || need_flush(iommu)) { + if (iommu->lazy_flush && + (n < pool->hint || need_flush(iommu))) { clear_flush(iommu); iommu->lazy_flush(iommu); } diff --git a/lib/once.c b/lib/once.c new file mode 100644 index 000000000000..05c8604627eb --- /dev/null +++ b/lib/once.c @@ -0,0 +1,62 @@ +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/once.h> +#include <linux/random.h> + +struct once_work { + struct work_struct work; + struct static_key *key; +}; + +static void once_deferred(struct work_struct *w) +{ + struct once_work *work; + + work = container_of(w, struct once_work, work); + BUG_ON(!static_key_enabled(work->key)); + static_key_slow_dec(work->key); + kfree(work); +} + +static void once_disable_jump(struct static_key *key) +{ + struct once_work *w; + + w = kmalloc(sizeof(*w), GFP_ATOMIC); + if (!w) + return; + + INIT_WORK(&w->work, once_deferred); + w->key = key; + schedule_work(&w->work); +} + +static DEFINE_SPINLOCK(once_lock); + +bool __do_once_start(bool *done, unsigned long *flags) + __acquires(once_lock) +{ + spin_lock_irqsave(&once_lock, *flags); + if (*done) { + spin_unlock_irqrestore(&once_lock, *flags); + /* Keep sparse happy by restoring an even lock count on + * this lock. In case we return here, we don't call into + * __do_once_done but return early in the DO_ONCE() macro. + */ + __acquire(once_lock); + return false; + } + + return true; +} +EXPORT_SYMBOL(__do_once_start); + +void __do_once_done(bool *done, struct static_key *once_key, + unsigned long *flags) + __releases(once_lock) +{ + *done = true; + spin_unlock_irqrestore(&once_lock, *flags); + once_disable_jump(once_key); +} +EXPORT_SYMBOL(__do_once_done); diff --git a/lib/random32.c b/lib/random32.c index 0bee183fa18f..12111910ccd0 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -181,7 +181,7 @@ void prandom_seed(u32 entropy) * No locking on the CPUs, but then somewhat random results are, well, * expected. */ - for_each_possible_cpu (i) { + for_each_possible_cpu(i) { struct rnd_state *state = &per_cpu(net_rand_state, i); state->s1 = __seed(state->s1 ^ entropy, 2U); @@ -201,7 +201,7 @@ static int __init prandom_init(void) prandom_state_selftest(); for_each_possible_cpu(i) { - struct rnd_state *state = &per_cpu(net_rand_state,i); + struct rnd_state *state = &per_cpu(net_rand_state, i); u32 weak_seed = (i + jiffies) ^ random_get_entropy(); prandom_seed_early(state, weak_seed, true); @@ -238,13 +238,30 @@ static void __init __prandom_start_seed_timer(void) add_timer(&seed_timer); } +void prandom_seed_full_state(struct rnd_state __percpu *pcpu_state) +{ + int i; + + for_each_possible_cpu(i) { + struct rnd_state *state = per_cpu_ptr(pcpu_state, i); + u32 seeds[4]; + + get_random_bytes(&seeds, sizeof(seeds)); + state->s1 = __seed(seeds[0], 2U); + state->s2 = __seed(seeds[1], 8U); + state->s3 = __seed(seeds[2], 16U); + state->s4 = __seed(seeds[3], 128U); + + prandom_warmup(state); + } +} + /* * Generate better values after random number generator * is fully initialized. */ static void __prandom_reseed(bool late) { - int i; unsigned long flags; static bool latch = false; static DEFINE_SPINLOCK(lock); @@ -266,19 +283,7 @@ static void __prandom_reseed(bool late) goto out; latch = true; - - for_each_possible_cpu(i) { - struct rnd_state *state = &per_cpu(net_rand_state,i); - u32 seeds[4]; - - get_random_bytes(&seeds, sizeof(seeds)); - state->s1 = __seed(seeds[0], 2U); - state->s2 = __seed(seeds[1], 8U); - state->s3 = __seed(seeds[2], 16U); - state->s4 = __seed(seeds[3], 128U); - - prandom_warmup(state); - } + prandom_seed_full_state(&net_rand_state); out: spin_unlock_irqrestore(&lock, flags); } diff --git a/lib/rhashtable.c b/lib/rhashtable.c index cc0c69710dcf..a54ff8949f91 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -187,10 +187,7 @@ static int rhashtable_rehash_one(struct rhashtable *ht, unsigned int old_hash) head = rht_dereference_bucket(new_tbl->buckets[new_hash], new_tbl, new_hash); - if (rht_is_a_nulls(head)) - INIT_RHT_NULLS_HEAD(entry->next, ht, new_hash); - else - RCU_INIT_POINTER(entry->next, head); + RCU_INIT_POINTER(entry->next, head); rcu_assign_pointer(new_tbl->buckets[new_hash], entry); spin_unlock(new_bucket_lock); diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 54036ce2e2dd..5939f63d90cd 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -59,7 +59,11 @@ void string_get_size(u64 size, u64 blk_size, const enum string_size_units units, } exp = divisor[units] / (u32)blk_size; - if (size >= exp) { + /* + * size must be strictly greater than exp here to ensure that remainder + * is greater than divisor[units] coming out of the if below. + */ + if (size > exp) { remainder = do_div(size, divisor[units]); remainder *= blk_size; i++; |