-static ssize_t get_pages_alloc_iovec(struct iov_iter *i,
- struct page ***pages, size_t maxsize,
- size_t *start)
-{
- size_t offset = i->iov_offset;
- const struct iovec *iov = i->iov;
- size_t len;
- unsigned long addr;
- void *p;
- 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);
- addr &= ~(PAGE_SIZE - 1);
- n = (len + PAGE_SIZE - 1) / PAGE_SIZE;
-
- p = kmalloc(n * sizeof(struct page *), GFP_KERNEL);
- if (!p)
- p = vmalloc(n * sizeof(struct page *));
- if (!p)
- return -ENOMEM;
-
- res = get_user_pages_fast(addr, n, (i->type & WRITE) != WRITE, p);
- if (unlikely(res < 0)) {
- kvfree(p);
- return res;
- }
- *pages = p;
- return (res == n ? len : res * PAGE_SIZE) - *start;
-}
-