diff options
| -rw-r--r-- | mm/iov_iter.c | 78 |
1 files changed, 28 insertions, 50 deletions
diff --git a/mm/iov_iter.c b/mm/iov_iter.c index bc666e7..75e29ef 100644 --- a/mm/iov_iter.c +++ b/mm/iov_iter.c @@ -428,34 +428,6 @@ void iov_iter_init(struct iov_iter *i, int direction, } EXPORT_SYMBOL(iov_iter_init); -static ssize_t get_pages_iovec(struct iov_iter *i, - struct page **pages, size_t maxsize, unsigned maxpages, - size_t *start) -{ - size_t offset = i->iov_offset; - const struct iovec *iov = i->iov; - size_t len; - unsigned long addr; - int n; - int res; - - len = iov->iov_len - offset; - if (len > i->count) - len = i->count; - if (len > maxsize) - len = maxsize; - addr = (unsigned long)iov->iov_base + offset; - len += *start = addr & (PAGE_SIZE - 1); - if (len > maxpages * PAGE_SIZE) - len = maxpages * PAGE_SIZE; - addr &= ~(PAGE_SIZE - 1); - n = (len + PAGE_SIZE - 1) / PAGE_SIZE; - res = get_user_pages_fast(addr, n, (i->type & WRITE) != WRITE, pages); - if (unlikely(res < 0)) - return res; - return (res == n ? len : res * PAGE_SIZE) - *start; -} - static ssize_t get_pages_alloc_iovec(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start) @@ -650,24 +622,6 @@ static size_t zero_bvec(size_t bytes, struct iov_iter *i) return wanted - bytes; } -static ssize_t get_pages_bvec(struct iov_iter *i, - struct page **pages, size_t maxsize, unsigned maxpages, - size_t *start) -{ - const struct bio_vec *bvec = i->bvec; - size_t len = bvec->bv_len - i->iov_offset; - if (len > i->count) - len = i->count; - if (len > maxsize) - len = maxsize; - /* can't be more than PAGE_SIZE */ - *start = bvec->bv_offset + i->iov_offset; - - get_page(*pages = bvec->bv_page); - - return len; -} - static ssize_t get_pages_alloc_bvec(struct iov_iter *i, struct page ***pages, size_t maxsize, size_t *start) @@ -792,10 +746,34 @@ ssize_t iov_iter_get_pages(struct iov_iter *i, struct page **pages, size_t maxsize, unsigned maxpages, size_t *start) { - if (i->type & ITER_BVEC) - return get_pages_bvec(i, pages, maxsize, maxpages, start); - else - return get_pages_iovec(i, pages, maxsize, maxpages, start); + if (maxsize > i->count) + maxsize = i->count; + + if (!maxsize) + return 0; + + iterate_all_kinds(i, maxsize, v, ({ + unsigned long addr = (unsigned long)v.iov_base; + size_t len = v.iov_len + (*start = addr & (PAGE_SIZE - 1)); + int n; + int res; + + if (len > maxpages * PAGE_SIZE) + len = maxpages * PAGE_SIZE; + addr &= ~(PAGE_SIZE - 1); + n = DIV_ROUND_UP(len, PAGE_SIZE); + res = get_user_pages_fast(addr, n, (i->type & WRITE) != WRITE, pages); + if (unlikely(res < 0)) + return res; + return (res == n ? len : res * PAGE_SIZE) - *start; + 0;}),({ + /* can't be more than PAGE_SIZE */ + *start = v.bv_offset; + get_page(*pages = v.bv_page); + return v.bv_len; + }) + ) + return 0; } EXPORT_SYMBOL(iov_iter_get_pages); |