diff options
| -rw-r--r-- | include/linux/uio.h | 24 | ||||
| -rw-r--r-- | lib/iov_iter.c | 85 |
2 files changed, 58 insertions, 51 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h index 68079e2f34eb..ad76eef356b0 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -19,21 +19,17 @@ struct kvec { enum iter_type { /* iter types */ - ITER_IOVEC = 4, - ITER_KVEC = 8, - ITER_BVEC = 16, - ITER_PIPE = 32, - ITER_DISCARD = 64, - ITER_XARRAY = 128, + ITER_IOVEC, + ITER_KVEC, + ITER_BVEC, + ITER_PIPE, + ITER_XARRAY, + ITER_DISCARD, }; struct iov_iter { - /* - * Bit 0 is the read/write bit, set if we're writing. - * Bit 1 is the BVEC_FLAG_NO_REF bit, set if type is a bvec and - * the caller isn't expecting to drop a page reference when done. - */ - unsigned int type; + u8 iter_type; + bool data_source; size_t iov_offset; size_t count; union { @@ -55,7 +51,7 @@ struct iov_iter { static inline enum iter_type iov_iter_type(const struct iov_iter *i) { - return i->type & ~(READ | WRITE); + return i->iter_type; } static inline bool iter_is_iovec(const struct iov_iter *i) @@ -90,7 +86,7 @@ static inline bool iov_iter_is_xarray(const struct iov_iter *i) static inline unsigned char iov_iter_rw(const struct iov_iter *i) { - return i->type & (READ | WRITE); + return i->data_source ? WRITE : READ; } /* diff --git a/lib/iov_iter.c b/lib/iov_iter.c index e6c5834da32d..03c4e677b075 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -489,19 +489,15 @@ void iov_iter_init(struct iov_iter *i, unsigned int direction, size_t count) { WARN_ON(direction & ~(READ | WRITE)); - direction &= READ | WRITE; - - /* It will get better. Eventually... */ - if (uaccess_kernel()) { - i->type = ITER_KVEC | direction; - i->kvec = (struct kvec *)iov; - } else { - i->type = ITER_IOVEC | direction; - i->iov = iov; - } - i->nr_segs = nr_segs; - i->iov_offset = 0; - i->count = count; + WARN_ON_ONCE(uaccess_kernel()); + *i = (struct iov_iter) { + .iter_type = ITER_IOVEC, + .data_source = direction, + .iov = iov, + .nr_segs = nr_segs, + .iov_offset = 0, + .count = count + }; } EXPORT_SYMBOL(iov_iter_init); @@ -1218,11 +1214,14 @@ void iov_iter_kvec(struct iov_iter *i, unsigned int direction, size_t count) { WARN_ON(direction & ~(READ | WRITE)); - i->type = ITER_KVEC | (direction & (READ | WRITE)); - i->kvec = kvec; - i->nr_segs = nr_segs; - i->iov_offset = 0; - i->count = count; + *i = (struct iov_iter){ + .iter_type = ITER_KVEC, + .data_source = direction, + .kvec = kvec, + .nr_segs = nr_segs, + .iov_offset = 0, + .count = count + }; } EXPORT_SYMBOL(iov_iter_kvec); @@ -1231,11 +1230,14 @@ void iov_iter_bvec(struct iov_iter *i, unsigned int direction, size_t count) { WARN_ON(direction & ~(READ | WRITE)); - i->type = ITER_BVEC | (direction & (READ | WRITE)); - i->bvec = bvec; - i->nr_segs = nr_segs; - i->iov_offset = 0; - i->count = count; + *i = (struct iov_iter){ + .iter_type = ITER_BVEC, + .data_source = direction, + .bvec = bvec, + .nr_segs = nr_segs, + .iov_offset = 0, + .count = count + }; } EXPORT_SYMBOL(iov_iter_bvec); @@ -1245,12 +1247,15 @@ void iov_iter_pipe(struct iov_iter *i, unsigned int direction, { BUG_ON(direction != READ); WARN_ON(pipe_full(pipe->head, pipe->tail, pipe->ring_size)); - i->type = ITER_PIPE | READ; - i->pipe = pipe; - i->head = pipe->head; - i->iov_offset = 0; - i->count = count; - i->start_head = i->head; + *i = (struct iov_iter){ + .iter_type = ITER_PIPE, + .data_source = false, + .pipe = pipe, + .head = pipe->head, + .start_head = pipe->head, + .iov_offset = 0, + .count = count + }; } EXPORT_SYMBOL(iov_iter_pipe); @@ -1271,11 +1276,14 @@ void iov_iter_xarray(struct iov_iter *i, unsigned int direction, struct xarray *xarray, loff_t start, size_t count) { BUG_ON(direction & ~1); - i->type = ITER_XARRAY | (direction & (READ | WRITE)); - i->xarray = xarray; - i->xarray_start = start; - i->count = count; - i->iov_offset = 0; + *i = (struct iov_iter) { + .iter_type = ITER_XARRAY, + .data_source = direction, + .xarray = xarray, + .xarray_start = start, + .count = count, + .iov_offset = 0 + }; } EXPORT_SYMBOL(iov_iter_xarray); @@ -1291,9 +1299,12 @@ EXPORT_SYMBOL(iov_iter_xarray); void iov_iter_discard(struct iov_iter *i, unsigned int direction, size_t count) { BUG_ON(direction != READ); - i->type = ITER_DISCARD | READ; - i->count = count; - i->iov_offset = 0; + *i = (struct iov_iter){ + .iter_type = ITER_DISCARD, + .data_source = false, + .count = count, + .iov_offset = 0 + }; } EXPORT_SYMBOL(iov_iter_discard); |