diff options
| -rw-r--r-- | fs/hugetlbfs/inode.c | 92 |
1 files changed, 34 insertions, 58 deletions
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index c274aca8e8dc..5291c14ee6b8 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -34,6 +34,7 @@ #include <linux/security.h> #include <linux/magic.h> #include <linux/migrate.h> +#include <linux/uio.h> #include <asm/uaccess.h> @@ -179,42 +180,33 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr, } #endif -static int +static size_t hugetlbfs_read_actor(struct page *page, unsigned long offset, - char __user *buf, unsigned long count, - unsigned long size) + struct iov_iter *to, unsigned long size) { - char *kaddr; - unsigned long left, copied = 0; + size_t copied = 0; int i, chunksize; - if (size > count) - size = count; - /* Find which 4k chunk and offset with in that chunk */ i = offset >> PAGE_CACHE_SHIFT; offset = offset & ~PAGE_CACHE_MASK; while (size) { + size_t n; chunksize = PAGE_CACHE_SIZE; if (offset) chunksize -= offset; if (chunksize > size) chunksize = size; - kaddr = kmap(&page[i]); - left = __copy_to_user(buf, kaddr + offset, chunksize); - kunmap(&page[i]); - if (left) { - copied += (chunksize - left); - break; - } + n = copy_page_to_iter(&page[i], offset, chunksize, to); + copied += n; + if (n != chunksize) + return copied; offset = 0; size -= chunksize; - buf += chunksize; - copied += chunksize; i++; } - return copied ? copied : -EFAULT; + return copied; } /* @@ -222,39 +214,34 @@ hugetlbfs_read_actor(struct page *page, unsigned long offset, * data. Its *very* similar to do_generic_mapping_read(), we can't use that * since it has PAGE_CACHE_SIZE assumptions. */ -static ssize_t hugetlbfs_read(struct file *filp, char __user *buf, - size_t len, loff_t *ppos) +static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to) { - struct hstate *h = hstate_file(filp); - struct address_space *mapping = filp->f_mapping; + struct file *file = iocb->ki_filp; + struct hstate *h = hstate_file(file); + struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; - unsigned long index = *ppos >> huge_page_shift(h); - unsigned long offset = *ppos & ~huge_page_mask(h); + unsigned long index = iocb->ki_pos >> huge_page_shift(h); + unsigned long offset = iocb->ki_pos & ~huge_page_mask(h); unsigned long end_index; loff_t isize; ssize_t retval = 0; - /* validate length */ - if (len == 0) - goto out; - - for (;;) { + while (iov_iter_count(to)) { struct page *page; - unsigned long nr, ret; - int ra; + size_t nr, copied; /* nr is the maximum number of bytes to copy from this page */ nr = huge_page_size(h); isize = i_size_read(inode); if (!isize) - goto out; + break; end_index = (isize - 1) >> huge_page_shift(h); - if (index >= end_index) { - if (index > end_index) - goto out; + if (index > end_index) + break; + if (index == end_index) { nr = ((isize - 1) & ~huge_page_mask(h)) + 1; if (nr <= offset) - goto out; + break; } nr = nr - offset; @@ -265,39 +252,27 @@ static ssize_t hugetlbfs_read(struct file *filp, char __user *buf, * We have a HOLE, zero out the user-buffer for the * length of the hole or request. */ - ret = len < nr ? len : nr; - if (clear_user(buf, ret)) - ra = -EFAULT; - else - ra = 0; + copied = iov_iter_zero(nr, to); } else { unlock_page(page); /* * We have the page, copy it to user space buffer. */ - ra = hugetlbfs_read_actor(page, offset, buf, len, nr); - ret = ra; + copied = hugetlbfs_read_actor(page, offset, to, nr); page_cache_release(page); } - if (ra < 0) { - if (retval == 0) - retval = ra; - goto out; + offset += copied; + retval += copied; + if (copied != nr && iov_iter_count(to)) { + if (!retval) + retval = -EFAULT; + break; } - - offset += ret; - retval += ret; - len -= ret; index += offset >> huge_page_shift(h); offset &= ~huge_page_mask(h); - - /* short read or no more work */ - if ((ret != nr) || (len == 0)) - break; } -out: - *ppos = ((loff_t)index << huge_page_shift(h)) + offset; + iocb->ki_pos = ((loff_t)index << huge_page_shift(h)) + offset; return retval; } @@ -721,7 +696,8 @@ static void init_once(void *foo) } const struct file_operations hugetlbfs_file_operations = { - .read = hugetlbfs_read, + .read = new_sync_read, + .read_iter = hugetlbfs_read_iter, .mmap = hugetlbfs_file_mmap, .fsync = noop_fsync, .get_unmapped_area = hugetlb_get_unmapped_area, |