Add two more helpers for copying memory between iov_iter and iomem, which will be used by the new PCM copy ops in a few drivers. The existing helpers became wrappers of those now.
Note that copy_from/to_iter() returns the copied bytes, hence the error condition is inverted from copy_from/to_user().
Signed-off-by: Takashi Iwai tiwai@suse.de --- include/sound/pcm.h | 5 ++++ sound/core/memory.c | 56 ++++++++++++++++++++++++++++++++++++++------- 2 files changed, 53 insertions(+), 8 deletions(-)
diff --git a/include/sound/pcm.h b/include/sound/pcm.h index ff4a0c1c93a2..f75beead79e3 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -1559,6 +1559,11 @@ static inline u64 pcm_format_to_bits(snd_pcm_format_t pcm_format) #define pcm_dbg(pcm, fmt, args...) \ dev_dbg((pcm)->card->dev, fmt, ##args)
+/* helpers for copying between iov_iter and iomem */ +int copy_to_iter_fromio(struct iov_iter *itert, const void __iomem *src, + size_t count); +int copy_from_iter_toio(void __iomem *dst, struct iov_iter *iter, size_t count); + struct snd_pcm_status64 { snd_pcm_state_t state; /* stream state */ u8 rsvd[4]; diff --git a/sound/core/memory.c b/sound/core/memory.c index 5d894dc32f7d..e5b54cd73ed6 100644 --- a/sound/core/memory.c +++ b/sound/core/memory.c @@ -9,6 +9,7 @@ #include <linux/io.h> #include <linux/uaccess.h> #include <sound/core.h> +#include <sound/pcm.h>
/** * copy_to_user_fromio - copy data from mmio-space to user-space @@ -21,9 +22,30 @@ * Return: Zero if successful, or non-zero on failure. */ int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size_t count) +{ + struct iov_iter iter; + + if (import_ubuf(ITER_DEST, dst, count, &iter)) + return -EFAULT; + return copy_to_iter_fromio(&iter, (const void __iomem *)src, count); +} +EXPORT_SYMBOL(copy_to_user_fromio); + +/** + * copy_to_iter_fromio - copy data from mmio-space to iov_iter + * @dst: the destination iov_iter + * @src: the source pointer on mmio + * @count: the data size to copy in bytes + * + * Copies the data from mmio-space to iov_iter. + * + * Return: Zero if successful, or non-zero on failure. + */ +int copy_to_iter_fromio(struct iov_iter *dst, const void __iomem *src, + size_t count) { #if defined(__i386__) || defined(CONFIG_SPARC32) - return copy_to_user(dst, (const void __force*)src, count) ? -EFAULT : 0; + return !copy_to_iter((const void __force *)src, count, dst) ? -EFAULT : 0; #else char buf[256]; while (count) { @@ -31,16 +53,15 @@ int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size if (c > sizeof(buf)) c = sizeof(buf); memcpy_fromio(buf, (void __iomem *)src, c); - if (copy_to_user(dst, buf, c)) + if (!copy_to_iter(buf, c, dst)) return -EFAULT; count -= c; - dst += c; src += c; } return 0; #endif } -EXPORT_SYMBOL(copy_to_user_fromio); +EXPORT_SYMBOL(copy_to_iter_fromio);
/** * copy_from_user_toio - copy data from user-space to mmio-space @@ -53,23 +74,42 @@ EXPORT_SYMBOL(copy_to_user_fromio); * Return: Zero if successful, or non-zero on failure. */ int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count) +{ + struct iov_iter iter; + + if (import_ubuf(ITER_SOURCE, (void __user *)src, count, &iter)) + return -EFAULT; + return copy_from_iter_toio((void __iomem *)dst, &iter, count); +} +EXPORT_SYMBOL(copy_from_user_toio); + +/** + * copy_from_iter_toio - copy data from iov_iter to mmio-space + * @dst: the destination pointer on mmio-space + * @src: the source iov_iter + * @count: the data size to copy in bytes + * + * Copies the data from iov_iter to mmio-space. + * + * Return: Zero if successful, or non-zero on failure. + */ +int copy_from_iter_toio(void __iomem *dst, struct iov_iter *src, size_t count) { #if defined(__i386__) || defined(CONFIG_SPARC32) - return copy_from_user((void __force *)dst, src, count) ? -EFAULT : 0; + return !copy_from_iter((void __force *)dst, count, src) ? -EFAULT : 0; #else char buf[256]; while (count) { size_t c = count; if (c > sizeof(buf)) c = sizeof(buf); - if (copy_from_user(buf, src, c)) + if (!copy_from_iter(buf, c, src)) return -EFAULT; memcpy_toio(dst, buf, c); count -= c; dst += c; - src += c; } return 0; #endif } -EXPORT_SYMBOL(copy_from_user_toio); +EXPORT_SYMBOL(copy_from_iter_toio);