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author | Thomas Gleixner <tglx@linutronix.de> | 2013-07-04 23:11:22 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2013-07-04 23:11:22 +0200 |
commit | 2b0f89317e99735bbf32eaede81f707f98ab1b5e (patch) | |
tree | 16daa236e21876b11f1c0b9256cd4046aadba020 /lib/iovec.c | |
parent | 07bd1172902e782f288e4d44b1fde7dec0f08b6f (diff) | |
parent | fa18f7bde3ad4568d1d343b60d963bfbd8dc3991 (diff) | |
download | lwn-2b0f89317e99735bbf32eaede81f707f98ab1b5e.tar.gz lwn-2b0f89317e99735bbf32eaede81f707f98ab1b5e.zip |
Merge branch 'timers/posix-cpu-timers-for-tglx' of
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks into timers/core
Frederic sayed: "Most of these patches have been hanging around for
several month now, in -mmotm for a significant chunk. They already
missed a few releases."
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'lib/iovec.c')
-rw-r--r-- | lib/iovec.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/lib/iovec.c b/lib/iovec.c new file mode 100644 index 000000000000..454baa88bf27 --- /dev/null +++ b/lib/iovec.c @@ -0,0 +1,53 @@ +#include <linux/uaccess.h> +#include <linux/export.h> +#include <linux/uio.h> + +/* + * Copy iovec to kernel. Returns -EFAULT on error. + * + * Note: this modifies the original iovec. + */ + +int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) +{ + while (len > 0) { + if (iov->iov_len) { + int copy = min_t(unsigned int, len, iov->iov_len); + if (copy_from_user(kdata, iov->iov_base, copy)) + return -EFAULT; + len -= copy; + kdata += copy; + iov->iov_base += copy; + iov->iov_len -= copy; + } + iov++; + } + + return 0; +} +EXPORT_SYMBOL(memcpy_fromiovec); + +/* + * Copy kernel to iovec. Returns -EFAULT on error. + * + * Note: this modifies the original iovec. + */ + +int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len) +{ + while (len > 0) { + if (iov->iov_len) { + int copy = min_t(unsigned int, iov->iov_len, len); + if (copy_to_user(iov->iov_base, kdata, copy)) + return -EFAULT; + kdata += copy; + len -= copy; + iov->iov_len -= copy; + iov->iov_base += copy; + } + iov++; + } + + return 0; +} +EXPORT_SYMBOL(memcpy_toiovec); |