powerpc: Adopt nvram module for PPC64

Adopt nvram module to reduce code duplication. This means CONFIG_NVRAM
becomes available to PPC64 builds. Previously it was only available to
PPC32 builds because it depended on CONFIG_GENERIC_NVRAM.

The IOC_NVRAM_GET_OFFSET ioctl as implemented on PPC64 validates the
offset returned by pmac_get_partition(). Do the same in the nvram module.

Note that the old PPC32 generic_nvram module lacked this test.
So when CONFIG_PPC32 && CONFIG_PPC_PMAC, the IOC_NVRAM_GET_OFFSET ioctl
would have returned 0 (always). But when CONFIG_PPC64 && CONFIG_PPC_PMAC,
the IOC_NVRAM_GET_OFFSET ioctl would have returned -1 (which is -EPERM)
when the requested partition was not found.

With this patch, the result is now -EINVAL on both PPC32 and PPC64 when
the requested PowerMac NVRAM partition is not found. This is a userspace-
visible change, in the non-existent partition case, which would be in
an error path for an IOC_NVRAM_GET_OFFSET ioctl syscall.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Finn Thain 2019-01-15 15:18:56 +11:00 коммит произвёл Greg Kroah-Hartman
Родитель 537f3286ad
Коммит 20e07af71f
7 изменённых файлов: 9 добавлений и 163 удалений

Просмотреть файл

@ -178,7 +178,7 @@ config PPC
select HAVE_ARCH_KGDB
select HAVE_ARCH_MMAP_RND_BITS
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
select HAVE_ARCH_NVRAM_OPS if PPC32
select HAVE_ARCH_NVRAM_OPS
select HAVE_ARCH_SECCOMP_FILTER
select HAVE_ARCH_TRACEHOOK
select HAVE_CBPF_JIT if !PPC64

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@ -7,12 +7,6 @@
* 2 of the License, or (at your option) any later version.
*
* /dev/nvram driver for PPC64
*
* This perhaps should live in drivers/char
*
* TODO: Split the /dev/nvram part (that one can use
* drivers/char/generic_nvram.c) from the arch & partition
* parsing code.
*/
#include <linux/types.h>
@ -714,137 +708,6 @@ static void oops_to_nvram(struct kmsg_dumper *dumper,
spin_unlock_irqrestore(&lock, flags);
}
static loff_t dev_nvram_llseek(struct file *file, loff_t offset, int origin)
{
if (ppc_md.nvram_size == NULL)
return -ENODEV;
return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
ppc_md.nvram_size());
}
static ssize_t dev_nvram_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t ret;
char *tmp = NULL;
ssize_t size;
if (!ppc_md.nvram_size) {
ret = -ENODEV;
goto out;
}
size = ppc_md.nvram_size();
if (size < 0) {
ret = size;
goto out;
}
if (*ppos >= size) {
ret = 0;
goto out;
}
count = min_t(size_t, count, size - *ppos);
count = min(count, PAGE_SIZE);
tmp = kmalloc(count, GFP_KERNEL);
if (!tmp) {
ret = -ENOMEM;
goto out;
}
ret = ppc_md.nvram_read(tmp, count, ppos);
if (ret <= 0)
goto out;
if (copy_to_user(buf, tmp, ret))
ret = -EFAULT;
out:
kfree(tmp);
return ret;
}
static ssize_t dev_nvram_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
ssize_t ret;
char *tmp = NULL;
ssize_t size;
ret = -ENODEV;
if (!ppc_md.nvram_size)
goto out;
ret = 0;
size = ppc_md.nvram_size();
if (*ppos >= size || size < 0)
goto out;
count = min_t(size_t, count, size - *ppos);
count = min(count, PAGE_SIZE);
tmp = memdup_user(buf, count);
if (IS_ERR(tmp)) {
ret = PTR_ERR(tmp);
goto out;
}
ret = ppc_md.nvram_write(tmp, count, ppos);
kfree(tmp);
out:
return ret;
}
static long dev_nvram_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
switch(cmd) {
#ifdef CONFIG_PPC_PMAC
case OBSOLETE_PMAC_NVRAM_GET_OFFSET:
printk(KERN_WARNING "nvram: Using obsolete PMAC_NVRAM_GET_OFFSET ioctl\n");
/* fall through */
case IOC_NVRAM_GET_OFFSET: {
int part, offset;
if (!machine_is(powermac))
return -EINVAL;
if (copy_from_user(&part, (void __user*)arg, sizeof(part)) != 0)
return -EFAULT;
if (part < pmac_nvram_OF || part > pmac_nvram_NR)
return -EINVAL;
offset = pmac_get_partition(part);
if (offset < 0)
return offset;
if (copy_to_user((void __user*)arg, &offset, sizeof(offset)) != 0)
return -EFAULT;
return 0;
}
#endif /* CONFIG_PPC_PMAC */
default:
return -EINVAL;
}
}
static const struct file_operations nvram_fops = {
.owner = THIS_MODULE,
.llseek = dev_nvram_llseek,
.read = dev_nvram_read,
.write = dev_nvram_write,
.unlocked_ioctl = dev_nvram_ioctl,
};
static struct miscdevice nvram_dev = {
NVRAM_MINOR,
"nvram",
&nvram_fops
};
#ifdef DEBUG_NVRAM
static void __init nvram_print_partitions(char * label)
{
@ -992,6 +855,8 @@ loff_t __init nvram_create_partition(const char *name, int sig,
long size = 0;
int rc;
BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16);
/* Convert sizes from bytes to blocks */
req_size = _ALIGN_UP(req_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
min_size = _ALIGN_UP(min_size, NVRAM_BLOCK_LEN) / NVRAM_BLOCK_LEN;
@ -1192,22 +1057,3 @@ int __init nvram_scan_partitions(void)
kfree(header);
return err;
}
static int __init nvram_init(void)
{
int rc;
BUILD_BUG_ON(NVRAM_BLOCK_LEN != 16);
if (ppc_md.nvram_size == NULL || ppc_md.nvram_size() <= 0)
return -ENODEV;
rc = misc_register(&nvram_dev);
if (rc != 0) {
printk(KERN_ERR "nvram_init: failed to register device\n");
return rc;
}
return rc;
}
device_initcall(nvram_init);

Просмотреть файл

@ -15,7 +15,5 @@ obj-$(CONFIG_PMAC_BACKLIGHT) += backlight.o
# need this to be a bool. Cheat here and pretend CONFIG_NVRAM=m is really
# CONFIG_NVRAM=y
obj-$(CONFIG_NVRAM:m=y) += nvram.o
# ppc64 pmac doesn't define CONFIG_NVRAM but needs nvram stuff
obj-$(CONFIG_PPC64) += nvram.o
obj-$(CONFIG_PPC32) += bootx_init.o
obj-$(CONFIG_SMP) += smp.o

Просмотреть файл

@ -316,7 +316,7 @@ static void __init pmac_setup_arch(void)
find_via_pmu();
smu_init();
#if IS_ENABLED(CONFIG_NVRAM) || defined(CONFIG_PPC64)
#if IS_ENABLED(CONFIG_NVRAM)
pmac_nvram_init();
#endif
#ifdef CONFIG_PPC32

Просмотреть файл

@ -68,7 +68,7 @@
long __init pmac_time_init(void)
{
s32 delta = 0;
#ifdef CONFIG_NVRAM
#if defined(CONFIG_NVRAM) && defined(CONFIG_PPC32)
int dst;
delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16;

Просмотреть файл

@ -7,8 +7,6 @@
* 2 of the License, or (at your option) any later version.
*
* /dev/nvram driver for PPC64
*
* This perhaps should live in drivers/char
*/

Просмотреть файл

@ -302,6 +302,8 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd,
if (part < pmac_nvram_OF || part > pmac_nvram_NR)
return -EINVAL;
offset = pmac_get_partition(part);
if (offset < 0)
return -EINVAL;
if (copy_to_user((void __user *)arg,
&offset, sizeof(offset)) != 0)
return -EFAULT;
@ -309,6 +311,7 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd,
}
#endif
break;
#ifdef CONFIG_PPC32
case IOC_NVRAM_SYNC:
if (ppc_md.nvram_sync != NULL) {
mutex_lock(&nvram_mutex);
@ -317,6 +320,7 @@ static long nvram_misc_ioctl(struct file *file, unsigned int cmd,
}
ret = 0;
break;
#endif
#elif defined(CONFIG_X86) || defined(CONFIG_M68K)
case NVRAM_INIT:
/* initialize NVRAM contents and checksum */