diff options
| -rw-r--r-- | drivers/char/nvram.c | 70 | ||||
| -rw-r--r-- | include/linux/nvram.h | 2 |
2 files changed, 42 insertions, 30 deletions
diff --git a/drivers/char/nvram.c b/drivers/char/nvram.c index 2df391f78986..f88ef41d0598 100644 --- a/drivers/char/nvram.c +++ b/drivers/char/nvram.c @@ -136,16 +136,25 @@ static void __nvram_set_checksum(void) __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1); } -#if 0 -void nvram_set_checksum(void) +static long pc_nvram_set_checksum(void) { - unsigned long flags; + spin_lock_irq(&rtc_lock); + __nvram_set_checksum(); + spin_unlock_irq(&rtc_lock); + return 0; +} - spin_lock_irqsave(&rtc_lock, flags); +static long pc_nvram_initialize(void) +{ + ssize_t i; + + spin_lock_irq(&rtc_lock); + for (i = 0; i < NVRAM_BYTES; ++i) + __nvram_write_byte(0, i); __nvram_set_checksum(); - spin_unlock_irqrestore(&rtc_lock, flags); + spin_unlock_irq(&rtc_lock); + return 0; } -#endif /* 0 */ static ssize_t pc_nvram_get_size(void) { @@ -156,6 +165,8 @@ const struct nvram_ops arch_nvram_ops = { .read_byte = pc_nvram_read_byte, .write_byte = pc_nvram_write_byte, .get_size = pc_nvram_get_size, + .set_checksum = pc_nvram_set_checksum, + .initialize = pc_nvram_initialize, }; EXPORT_SYMBOL(arch_nvram_ops); #endif /* CONFIG_X86 */ @@ -241,51 +252,50 @@ checksum_err: static long nvram_misc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - int i; + long ret = -ENOTTY; switch (cmd) { - case NVRAM_INIT: /* initialize NVRAM contents and checksum */ if (!capable(CAP_SYS_ADMIN)) return -EACCES; - mutex_lock(&nvram_mutex); - spin_lock_irq(&rtc_lock); - - for (i = 0; i < NVRAM_BYTES; ++i) - __nvram_write_byte(0, i); - __nvram_set_checksum(); - - spin_unlock_irq(&rtc_lock); - mutex_unlock(&nvram_mutex); - return 0; - + if (arch_nvram_ops.initialize != NULL) { + mutex_lock(&nvram_mutex); + ret = arch_nvram_ops.initialize(); + mutex_unlock(&nvram_mutex); + } + break; case NVRAM_SETCKS: /* just set checksum, contents unchanged (maybe useful after * checksum garbaged somehow...) */ if (!capable(CAP_SYS_ADMIN)) return -EACCES; - mutex_lock(&nvram_mutex); - spin_lock_irq(&rtc_lock); - __nvram_set_checksum(); - spin_unlock_irq(&rtc_lock); - mutex_unlock(&nvram_mutex); - return 0; - - default: - return -ENOTTY; + if (arch_nvram_ops.set_checksum != NULL) { + mutex_lock(&nvram_mutex); + ret = arch_nvram_ops.set_checksum(); + mutex_unlock(&nvram_mutex); + } + break; } + return ret; } static int nvram_misc_open(struct inode *inode, struct file *file) { spin_lock(&nvram_state_lock); + /* Prevent multiple readers/writers if desired. */ if ((nvram_open_cnt && (file->f_flags & O_EXCL)) || - (nvram_open_mode & NVRAM_EXCL) || - ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) { + (nvram_open_mode & NVRAM_EXCL)) { + spin_unlock(&nvram_state_lock); + return -EBUSY; + } + + /* Prevent multiple writers if the set_checksum ioctl is implemented. */ + if ((arch_nvram_ops.set_checksum != NULL) && + (file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE)) { spin_unlock(&nvram_state_lock); return -EBUSY; } diff --git a/include/linux/nvram.h b/include/linux/nvram.h index bb4ea8cc6ea6..31c763087746 100644 --- a/include/linux/nvram.h +++ b/include/linux/nvram.h @@ -31,6 +31,8 @@ struct nvram_ops { void (*write_byte)(unsigned char, int); ssize_t (*read)(char *, size_t, loff_t *); ssize_t (*write)(char *, size_t, loff_t *); + long (*initialize)(void); + long (*set_checksum)(void); }; extern const struct nvram_ops arch_nvram_ops; |