diff options
Diffstat (limited to 'fs/pstore/ram_core.c')
-rw-r--r-- | fs/pstore/ram_core.c | 96 |
1 files changed, 50 insertions, 46 deletions
diff --git a/fs/pstore/ram_core.c b/fs/pstore/ram_core.c index 76c3f80..3975dee 100644 --- a/fs/pstore/ram_core.c +++ b/fs/pstore/ram_core.c @@ -17,15 +17,16 @@ #include <linux/device.h> #include <linux/err.h> #include <linux/errno.h> -#include <linux/kernel.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/kernel.h> #include <linux/list.h> #include <linux/memblock.h> +#include <linux/pstore_ram.h> #include <linux/rslib.h> #include <linux/slab.h> +#include <linux/uaccess.h> #include <linux/vmalloc.h> -#include <linux/pstore_ram.h> #include <asm/page.h> struct persistent_ram_buffer { @@ -47,43 +48,10 @@ static inline size_t buffer_start(struct persistent_ram_zone *prz) return atomic_read(&prz->buffer->start); } -/* increase and wrap the start pointer, returning the old value */ -static size_t buffer_start_add_atomic(struct persistent_ram_zone *prz, size_t a) -{ - int old; - int new; - - do { - old = atomic_read(&prz->buffer->start); - new = old + a; - while (unlikely(new >= prz->buffer_size)) - new -= prz->buffer_size; - } while (atomic_cmpxchg(&prz->buffer->start, old, new) != old); - - return old; -} - -/* increase the size counter until it hits the max size */ -static void buffer_size_add_atomic(struct persistent_ram_zone *prz, size_t a) -{ - size_t old; - size_t new; - - if (atomic_read(&prz->buffer->size) == prz->buffer_size) - return; - - do { - old = atomic_read(&prz->buffer->size); - new = old + a; - if (new > prz->buffer_size) - new = prz->buffer_size; - } while (atomic_cmpxchg(&prz->buffer->size, old, new) != old); -} - static DEFINE_RAW_SPINLOCK(buffer_lock); /* increase and wrap the start pointer, returning the old value */ -static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a) +static size_t buffer_start_add(struct persistent_ram_zone *prz, size_t a) { int old; int new; @@ -103,7 +71,7 @@ static size_t buffer_start_add_locked(struct persistent_ram_zone *prz, size_t a) } /* increase the size counter until it hits the max size */ -static void buffer_size_add_locked(struct persistent_ram_zone *prz, size_t a) +static void buffer_size_add(struct persistent_ram_zone *prz, size_t a) { size_t old; size_t new; @@ -124,9 +92,6 @@ exit: raw_spin_unlock_irqrestore(&buffer_lock, flags); } -static size_t (*buffer_start_add)(struct persistent_ram_zone *, size_t) = buffer_start_add_atomic; -static void (*buffer_size_add)(struct persistent_ram_zone *, size_t) = buffer_size_add_atomic; - static void notrace persistent_ram_encode_rs8(struct persistent_ram_zone *prz, uint8_t *data, size_t len, uint8_t *ecc) { @@ -299,10 +264,20 @@ static void notrace persistent_ram_update(struct persistent_ram_zone *prz, const void *s, unsigned int start, unsigned int count) { struct persistent_ram_buffer *buffer = prz->buffer; - memcpy(buffer->data + start, s, count); + memcpy_toio(buffer->data + start, s, count); persistent_ram_update_ecc(prz, start, count); } +static int notrace persistent_ram_update_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int start, unsigned int count) +{ + struct persistent_ram_buffer *buffer = prz->buffer; + int ret = unlikely(__copy_from_user(buffer->data + start, s, count)) ? + -EFAULT : 0; + persistent_ram_update_ecc(prz, start, count); + return ret; +} + void persistent_ram_save_old(struct persistent_ram_zone *prz) { struct persistent_ram_buffer *buffer = prz->buffer; @@ -322,8 +297,8 @@ void persistent_ram_save_old(struct persistent_ram_zone *prz) } prz->old_log_size = size; - memcpy(prz->old_log, &buffer->data[start], size - start); - memcpy(prz->old_log + size - start, &buffer->data[0], start); + memcpy_fromio(prz->old_log, &buffer->data[start], size - start); + memcpy_fromio(prz->old_log + size - start, &buffer->data[0], start); } int notrace persistent_ram_write(struct persistent_ram_zone *prz, @@ -356,6 +331,38 @@ int notrace persistent_ram_write(struct persistent_ram_zone *prz, return count; } +int notrace persistent_ram_write_user(struct persistent_ram_zone *prz, + const void __user *s, unsigned int count) +{ + int rem, ret = 0, c = count; + size_t start; + + if (unlikely(!access_ok(VERIFY_READ, s, count))) + return -EFAULT; + if (unlikely(c > prz->buffer_size)) { + s += c - prz->buffer_size; + c = prz->buffer_size; + } + + buffer_size_add(prz, c); + + start = buffer_start_add(prz, c); + + rem = prz->buffer_size - start; + if (unlikely(rem < c)) { + ret = persistent_ram_update_user(prz, s, start, rem); + s += rem; + c -= rem; + start = 0; + } + if (likely(!ret)) + ret = persistent_ram_update_user(prz, s, start, c); + + persistent_ram_update_header_ecc(prz); + + return unlikely(ret) ? ret : count; +} + size_t persistent_ram_old_size(struct persistent_ram_zone *prz) { return prz->old_log_size; @@ -426,9 +433,6 @@ static void *persistent_ram_iomap(phys_addr_t start, size_t size, return NULL; } - buffer_start_add = buffer_start_add_locked; - buffer_size_add = buffer_size_add_locked; - if (memtype) va = ioremap(start, size); else |