Add the equivalent of iov_iter_fault_in_readable(), but for pages that will be written to.
While at it, fix an indentation error in iov_iter_fault_in_readable(). Signed-off-by: Andreas Gruenbacher <[email protected]> --- include/linux/uio.h | 1 + lib/iov_iter.c | 20 +++++++++++++++++++- 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/include/linux/uio.h b/include/linux/uio.h index d3ec87706d75..6811eb6ac6e3 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -124,6 +124,7 @@ size_t iov_iter_copy_from_user_atomic(struct page *page, void iov_iter_advance(struct iov_iter *i, size_t bytes); void iov_iter_revert(struct iov_iter *i, size_t bytes); int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes); +int iov_iter_fault_in_writeable(struct iov_iter *i, size_t bytes); size_t iov_iter_single_seg_count(const struct iov_iter *i); size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes, struct iov_iter *i); diff --git a/lib/iov_iter.c b/lib/iov_iter.c index c701b7a187f2..317c94eac907 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -480,13 +480,31 @@ int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes) iterate_iovec(i, bytes, v, iov, skip, ({ err = fault_in_pages_readable(v.iov_base, v.iov_len); if (unlikely(err)) - return err; + return err; 0;})) } return 0; } EXPORT_SYMBOL(iov_iter_fault_in_readable); +int iov_iter_fault_in_writeable(struct iov_iter *i, size_t bytes) +{ + size_t skip = i->iov_offset; + const struct iovec *iov; + int err; + struct iovec v; + + if (!(i->type & (ITER_BVEC|ITER_KVEC))) { + iterate_iovec(i, bytes, v, iov, skip, ({ + err = fault_in_pages_writeable(v.iov_base, v.iov_len); + if (unlikely(err)) + return err; + 0;})) + } + return 0; +} +EXPORT_SYMBOL(iov_iter_fault_in_writeable); + void iov_iter_init(struct iov_iter *i, unsigned int direction, const struct iovec *iov, unsigned long nr_segs, size_t count) -- 2.26.3
