diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Makefile | 2 | ||||
-rw-r--r-- | lib/iovec.c | 53 | ||||
-rw-r--r-- | lib/klist.c | 2 |
3 files changed, 55 insertions, 2 deletions
diff --git a/lib/Makefile b/lib/Makefile index e9c52e1b853a..c55a037a354e 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -23,7 +23,7 @@ lib-y += kobject.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ - gcd.o lcm.o list_sort.o uuid.o flex_array.o \ + gcd.o lcm.o list_sort.o uuid.o flex_array.o iovec.o \ bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o 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); diff --git a/lib/klist.c b/lib/klist.c index 0874e41609a6..358a368a2947 100644 --- a/lib/klist.c +++ b/lib/klist.c @@ -193,10 +193,10 @@ static void klist_release(struct kref *kref) if (waiter->node != n) continue; + list_del(&waiter->list); waiter->woken = 1; mb(); wake_up_process(waiter->process); - list_del(&waiter->list); } spin_unlock(&klist_remove_lock); knode_set_klist(n, NULL); |