diff options
Diffstat (limited to 'lib/iov_iter.c')
| -rw-r--r-- | lib/iov_iter.c | 86 |
1 files changed, 61 insertions, 25 deletions
diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 7ebccb5c1637..621984743268 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -560,6 +560,44 @@ static size_t copy_pipe_to_iter(const void *addr, size_t bytes, return bytes; } +static __wsum csum_and_memcpy(void *to, const void *from, size_t len, + __wsum sum, size_t off) +{ + __wsum next = csum_partial_copy_nocheck(from, to, len, 0); + return csum_block_add(sum, next, off); +} + +static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes, + __wsum *csum, struct iov_iter *i) +{ + struct pipe_inode_info *pipe = i->pipe; + size_t n, r; + size_t off = 0; + __wsum sum = *csum; + int idx; + + if (!sanity(i)) + return 0; + + bytes = n = push_pipe(i, bytes, &idx, &r); + if (unlikely(!n)) + return 0; + for ( ; n; idx = next_idx(idx, pipe), r = 0) { + size_t chunk = min_t(size_t, n, PAGE_SIZE - r); + char *p = kmap_atomic(pipe->bufs[idx].page); + sum = csum_and_memcpy(p + r, addr, chunk, sum, off); + kunmap_atomic(p); + i->idx = idx; + i->iov_offset = r + chunk; + n -= chunk; + off += chunk; + addr += chunk; + } + i->count -= bytes; + *csum = sum; + return bytes; +} + size_t _copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i) { const char *from = addr; @@ -1368,17 +1406,15 @@ size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, err ? v.iov_len : 0; }), ({ char *p = kmap_atomic(v.bv_page); - next = csum_partial_copy_nocheck(p + v.bv_offset, - (to += v.bv_len) - v.bv_len, - v.bv_len, 0); + sum = csum_and_memcpy((to += v.bv_len) - v.bv_len, + p + v.bv_offset, v.bv_len, + sum, off); kunmap_atomic(p); - sum = csum_block_add(sum, next, off); off += v.bv_len; }),({ - next = csum_partial_copy_nocheck(v.iov_base, - (to += v.iov_len) - v.iov_len, - v.iov_len, 0); - sum = csum_block_add(sum, next, off); + sum = csum_and_memcpy((to += v.iov_len) - v.iov_len, + v.iov_base, v.iov_len, + sum, off); off += v.iov_len; }) ) @@ -1412,17 +1448,15 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, 0; }), ({ char *p = kmap_atomic(v.bv_page); - next = csum_partial_copy_nocheck(p + v.bv_offset, - (to += v.bv_len) - v.bv_len, - v.bv_len, 0); + sum = csum_and_memcpy((to += v.bv_len) - v.bv_len, + p + v.bv_offset, v.bv_len, + sum, off); kunmap_atomic(p); - sum = csum_block_add(sum, next, off); off += v.bv_len; }),({ - next = csum_partial_copy_nocheck(v.iov_base, - (to += v.iov_len) - v.iov_len, - v.iov_len, 0); - sum = csum_block_add(sum, next, off); + sum = csum_and_memcpy((to += v.iov_len) - v.iov_len, + v.iov_base, v.iov_len, + sum, off); off += v.iov_len; }) ) @@ -1438,8 +1472,12 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, __wsum *csum, const char *from = addr; __wsum sum, next; size_t off = 0; + + if (unlikely(iov_iter_is_pipe(i))) + return csum_and_copy_to_pipe_iter(addr, bytes, csum, i); + sum = *csum; - if (unlikely(iov_iter_is_pipe(i) || iov_iter_is_discard(i))) { + if (unlikely(iov_iter_is_discard(i))) { WARN_ON(1); /* for now */ return 0; } @@ -1455,17 +1493,15 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, __wsum *csum, err ? v.iov_len : 0; }), ({ char *p = kmap_atomic(v.bv_page); - next = csum_partial_copy_nocheck((from += v.bv_len) - v.bv_len, - p + v.bv_offset, - v.bv_len, 0); + sum = csum_and_memcpy(p + v.bv_offset, + (from += v.bv_len) - v.bv_len, + v.bv_len, sum, off); kunmap_atomic(p); - sum = csum_block_add(sum, next, off); off += v.bv_len; }),({ - next = csum_partial_copy_nocheck((from += v.iov_len) - v.iov_len, - v.iov_base, - v.iov_len, 0); - sum = csum_block_add(sum, next, off); + sum = csum_and_memcpy(v.iov_base, + (from += v.iov_len) - v.iov_len, + v.iov_len, sum, off); off += v.iov_len; }) ) |