diff options
| -rw-r--r-- | include/linux/uio.h | 4 | ||||
| -rw-r--r-- | lib/iov_iter.c | 22 |
2 files changed, 26 insertions, 0 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 5885daeae721..e67e12adb136 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -244,4 +244,8 @@ int compat_import_iovec(int type, const struct compat_iovec __user * uvector, int import_single_range(int type, void __user *buf, size_t len, struct iovec *iov, struct iov_iter *i); +int iov_iter_for_each_range(struct iov_iter *i, size_t bytes, + int (*f)(struct kvec *vec, void *context), + void *context); + #endif diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 1c1c06ddc20a..970212670b6a 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -1446,3 +1446,25 @@ int import_single_range(int rw, void __user *buf, size_t len, return 0; } EXPORT_SYMBOL(import_single_range); + +int iov_iter_for_each_range(struct iov_iter *i, size_t bytes, + int (*f)(struct kvec *vec, void *context), + void *context) +{ + struct kvec w; + int err = -EINVAL; + if (!bytes) + return 0; + + iterate_all_kinds(i, bytes, v, -EINVAL, ({ + w.iov_base = kmap(v.bv_page) + v.bv_offset; + w.iov_len = v.bv_len; + err = f(&w, context); + kunmap(v.bv_page); + err;}), ({ + w = v; + err = f(&w, context);}) + ) + return err; +} +EXPORT_SYMBOL(iov_iter_for_each_range); |