diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 34 |
1 files changed, 20 insertions, 14 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 4cbc73173701..c033135f2a67 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -263,6 +263,7 @@ #include <linux/syscalls.h> #include <linux/completion.h> #include <linux/uuid.h> +#include <linux/locallock.h> #include <crypto/chacha20.h> #include <asm/processor.h> @@ -1087,8 +1088,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num) } sample; long delta, delta2, delta3; - preempt_disable(); - sample.jiffies = jiffies; sample.cycles = random_get_entropy(); sample.num = num; @@ -1129,7 +1128,6 @@ static void add_timer_randomness(struct timer_rand_state *state, unsigned num) */ credit_entropy_bits(r, min_t(int, fls(delta>>1), 11)); } - preempt_enable(); } void add_input_randomness(unsigned int type, unsigned int code, @@ -1186,28 +1184,27 @@ static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs) return *ptr; } -void add_interrupt_randomness(int irq, int irq_flags) +void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) { struct entropy_store *r; struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); - struct pt_regs *regs = get_irq_regs(); unsigned long now = jiffies; cycles_t cycles = random_get_entropy(); __u32 c_high, j_high; - __u64 ip; unsigned long seed; int credit = 0; if (cycles == 0) - cycles = get_reg(fast_pool, regs); + cycles = get_reg(fast_pool, NULL); c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0; j_high = (sizeof(now) > 4) ? now >> 32 : 0; fast_pool->pool[0] ^= cycles ^ j_high ^ irq; fast_pool->pool[1] ^= now ^ c_high; - ip = regs ? instruction_pointer(regs) : _RET_IP_; + if (!ip) + ip = _RET_IP_; fast_pool->pool[2] ^= ip; fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 : - get_reg(fast_pool, regs); + get_reg(fast_pool, NULL); fast_mix(fast_pool); add_interrupt_bench(cycles); @@ -1668,7 +1665,7 @@ void get_random_bytes_arch(void *buf, int nbytes) if (!arch_get_random_long(&v)) break; - + memcpy(p, &v, chunk); p += chunk; nbytes -= chunk; @@ -2122,18 +2119,22 @@ struct batched_entropy { * the goal of being quite fast and not depleting entropy. */ static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_long); +static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_long_lock); unsigned long get_random_long(void) { unsigned long ret; struct batched_entropy *batch; - batch = &get_cpu_var(batched_entropy_long); + if (arch_get_random_long(&ret)) + return ret; + + batch = &get_locked_var(batched_entropy_long_lock, batched_entropy_long); if (batch->position % ARRAY_SIZE(batch->entropy_long) == 0) { extract_crng((u8 *)batch->entropy_long); batch->position = 0; } ret = batch->entropy_long[batch->position++]; - put_cpu_var(batched_entropy_long); + put_locked_var(batched_entropy_long_lock, batched_entropy_long); return ret; } EXPORT_SYMBOL(get_random_long); @@ -2145,18 +2146,23 @@ unsigned int get_random_int(void) } #else static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_int); +static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_int_lock); + unsigned int get_random_int(void) { unsigned int ret; struct batched_entropy *batch; - batch = &get_cpu_var(batched_entropy_int); + if (arch_get_random_int(&ret)) + return ret; + + batch = &get_locked_var(batched_entropy_int_lock, batched_entropy_int); if (batch->position % ARRAY_SIZE(batch->entropy_int) == 0) { extract_crng((u8 *)batch->entropy_int); batch->position = 0; } ret = batch->entropy_int[batch->position++]; - put_cpu_var(batched_entropy_int); + put_locked_var(batched_entropy_int_lock, batched_entropy_int); return ret; } #endif |