forked from Minki/linux
vfs: move the remap range helpers to remap_range.c
Complete the migration by moving the file remapping helper functions out of read_write.c and into remap_range.c. This reduces the clutter in the first file and (eventually) will make it so that we can compile out the second file if it isn't needed. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Darrick J. Wong
parent
02e83f46eb
commit
1b2c54d63c
473
fs/read_write.c
473
fs/read_write.c
@ -1832,476 +1832,3 @@ out1:
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out2:
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return ret;
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}
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static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
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bool write)
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{
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struct inode *inode = file_inode(file);
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if (unlikely(pos < 0 || len < 0))
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return -EINVAL;
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if (unlikely((loff_t) (pos + len) < 0))
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return -EINVAL;
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if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
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loff_t end = len ? pos + len - 1 : OFFSET_MAX;
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int retval;
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retval = locks_mandatory_area(inode, file, pos, end,
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write ? F_WRLCK : F_RDLCK);
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if (retval < 0)
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return retval;
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}
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return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
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}
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/*
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* Ensure that we don't remap a partial EOF block in the middle of something
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* else. Assume that the offsets have already been checked for block
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* alignment.
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*
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* For clone we only link a partial EOF block above or at the destination file's
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* EOF. For deduplication we accept a partial EOF block only if it ends at the
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* destination file's EOF (can not link it into the middle of a file).
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*
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* Shorten the request if possible.
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*/
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static int generic_remap_check_len(struct inode *inode_in,
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struct inode *inode_out,
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loff_t pos_out,
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loff_t *len,
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unsigned int remap_flags)
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{
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u64 blkmask = i_blocksize(inode_in) - 1;
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loff_t new_len = *len;
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if ((*len & blkmask) == 0)
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return 0;
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if (pos_out + *len < i_size_read(inode_out))
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new_len &= ~blkmask;
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if (new_len == *len)
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return 0;
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if (remap_flags & REMAP_FILE_CAN_SHORTEN) {
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*len = new_len;
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return 0;
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}
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return (remap_flags & REMAP_FILE_DEDUP) ? -EBADE : -EINVAL;
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}
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/* Read a page's worth of file data into the page cache. */
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static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset)
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{
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struct page *page;
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page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL);
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if (IS_ERR(page))
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return page;
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if (!PageUptodate(page)) {
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put_page(page);
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return ERR_PTR(-EIO);
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}
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return page;
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}
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/*
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* Lock two pages, ensuring that we lock in offset order if the pages are from
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* the same file.
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*/
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static void vfs_lock_two_pages(struct page *page1, struct page *page2)
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{
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/* Always lock in order of increasing index. */
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if (page1->index > page2->index)
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swap(page1, page2);
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lock_page(page1);
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if (page1 != page2)
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lock_page(page2);
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}
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/* Unlock two pages, being careful not to unlock the same page twice. */
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static void vfs_unlock_two_pages(struct page *page1, struct page *page2)
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{
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unlock_page(page1);
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if (page1 != page2)
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unlock_page(page2);
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}
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/*
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* Compare extents of two files to see if they are the same.
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* Caller must have locked both inodes to prevent write races.
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*/
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static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
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struct inode *dest, loff_t destoff,
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loff_t len, bool *is_same)
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{
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loff_t src_poff;
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loff_t dest_poff;
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void *src_addr;
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void *dest_addr;
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struct page *src_page;
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struct page *dest_page;
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loff_t cmp_len;
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bool same;
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int error;
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error = -EINVAL;
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same = true;
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while (len) {
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src_poff = srcoff & (PAGE_SIZE - 1);
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dest_poff = destoff & (PAGE_SIZE - 1);
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cmp_len = min(PAGE_SIZE - src_poff,
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PAGE_SIZE - dest_poff);
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cmp_len = min(cmp_len, len);
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if (cmp_len <= 0)
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goto out_error;
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src_page = vfs_dedupe_get_page(src, srcoff);
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if (IS_ERR(src_page)) {
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error = PTR_ERR(src_page);
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goto out_error;
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}
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dest_page = vfs_dedupe_get_page(dest, destoff);
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if (IS_ERR(dest_page)) {
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error = PTR_ERR(dest_page);
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put_page(src_page);
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goto out_error;
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}
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vfs_lock_two_pages(src_page, dest_page);
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/*
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* Now that we've locked both pages, make sure they're still
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* mapped to the file data we're interested in. If not,
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* someone is invalidating pages on us and we lose.
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*/
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if (!PageUptodate(src_page) || !PageUptodate(dest_page) ||
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src_page->mapping != src->i_mapping ||
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dest_page->mapping != dest->i_mapping) {
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same = false;
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goto unlock;
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}
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src_addr = kmap_atomic(src_page);
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dest_addr = kmap_atomic(dest_page);
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flush_dcache_page(src_page);
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flush_dcache_page(dest_page);
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if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
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same = false;
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kunmap_atomic(dest_addr);
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kunmap_atomic(src_addr);
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unlock:
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vfs_unlock_two_pages(src_page, dest_page);
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put_page(dest_page);
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put_page(src_page);
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if (!same)
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break;
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srcoff += cmp_len;
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destoff += cmp_len;
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len -= cmp_len;
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}
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*is_same = same;
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return 0;
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out_error:
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return error;
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}
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/*
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* Check that the two inodes are eligible for cloning, the ranges make
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* sense, and then flush all dirty data. Caller must ensure that the
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* inodes have been locked against any other modifications.
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*
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* If there's an error, then the usual negative error code is returned.
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* Otherwise returns 0 with *len set to the request length.
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*/
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int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
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struct file *file_out, loff_t pos_out,
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loff_t *len, unsigned int remap_flags)
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{
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struct inode *inode_in = file_inode(file_in);
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struct inode *inode_out = file_inode(file_out);
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bool same_inode = (inode_in == inode_out);
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int ret;
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/* Don't touch certain kinds of inodes */
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if (IS_IMMUTABLE(inode_out))
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return -EPERM;
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if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
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return -ETXTBSY;
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/* Don't reflink dirs, pipes, sockets... */
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if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
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return -EISDIR;
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if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
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return -EINVAL;
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/* Zero length dedupe exits immediately; reflink goes to EOF. */
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if (*len == 0) {
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loff_t isize = i_size_read(inode_in);
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if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize)
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return 0;
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if (pos_in > isize)
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return -EINVAL;
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*len = isize - pos_in;
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if (*len == 0)
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return 0;
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}
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/* Check that we don't violate system file offset limits. */
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ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len,
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remap_flags);
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if (ret)
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return ret;
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/* Wait for the completion of any pending IOs on both files */
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inode_dio_wait(inode_in);
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if (!same_inode)
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inode_dio_wait(inode_out);
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ret = filemap_write_and_wait_range(inode_in->i_mapping,
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pos_in, pos_in + *len - 1);
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if (ret)
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return ret;
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ret = filemap_write_and_wait_range(inode_out->i_mapping,
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pos_out, pos_out + *len - 1);
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if (ret)
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return ret;
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/*
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* Check that the extents are the same.
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*/
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if (remap_flags & REMAP_FILE_DEDUP) {
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bool is_same = false;
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ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
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inode_out, pos_out, *len, &is_same);
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if (ret)
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return ret;
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if (!is_same)
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return -EBADE;
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}
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ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
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remap_flags);
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if (ret)
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return ret;
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/* If can't alter the file contents, we're done. */
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if (!(remap_flags & REMAP_FILE_DEDUP))
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ret = file_modified(file_out);
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return ret;
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}
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EXPORT_SYMBOL(generic_remap_file_range_prep);
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loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
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struct file *file_out, loff_t pos_out,
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loff_t len, unsigned int remap_flags)
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{
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loff_t ret;
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WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP);
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/*
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* FICLONE/FICLONERANGE ioctls enforce that src and dest files are on
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* the same mount. Practically, they only need to be on the same file
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* system.
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*/
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if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
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return -EXDEV;
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ret = generic_file_rw_checks(file_in, file_out);
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if (ret < 0)
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return ret;
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if (!file_in->f_op->remap_file_range)
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return -EOPNOTSUPP;
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ret = remap_verify_area(file_in, pos_in, len, false);
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if (ret)
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return ret;
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ret = remap_verify_area(file_out, pos_out, len, true);
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if (ret)
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return ret;
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ret = file_in->f_op->remap_file_range(file_in, pos_in,
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file_out, pos_out, len, remap_flags);
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if (ret < 0)
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return ret;
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fsnotify_access(file_in);
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fsnotify_modify(file_out);
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return ret;
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}
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EXPORT_SYMBOL(do_clone_file_range);
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loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
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struct file *file_out, loff_t pos_out,
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loff_t len, unsigned int remap_flags)
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{
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loff_t ret;
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file_start_write(file_out);
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ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len,
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remap_flags);
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file_end_write(file_out);
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return ret;
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}
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EXPORT_SYMBOL(vfs_clone_file_range);
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/* Check whether we are allowed to dedupe the destination file */
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static bool allow_file_dedupe(struct file *file)
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{
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if (capable(CAP_SYS_ADMIN))
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return true;
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if (file->f_mode & FMODE_WRITE)
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return true;
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if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
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return true;
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if (!inode_permission(file_inode(file), MAY_WRITE))
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return true;
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return false;
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}
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loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
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struct file *dst_file, loff_t dst_pos,
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loff_t len, unsigned int remap_flags)
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{
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loff_t ret;
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WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP |
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REMAP_FILE_CAN_SHORTEN));
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ret = mnt_want_write_file(dst_file);
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if (ret)
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return ret;
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ret = remap_verify_area(dst_file, dst_pos, len, true);
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if (ret < 0)
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goto out_drop_write;
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ret = -EPERM;
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if (!allow_file_dedupe(dst_file))
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goto out_drop_write;
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ret = -EXDEV;
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if (src_file->f_path.mnt != dst_file->f_path.mnt)
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goto out_drop_write;
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ret = -EISDIR;
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if (S_ISDIR(file_inode(dst_file)->i_mode))
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goto out_drop_write;
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ret = -EINVAL;
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if (!dst_file->f_op->remap_file_range)
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goto out_drop_write;
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if (len == 0) {
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ret = 0;
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goto out_drop_write;
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}
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ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file,
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dst_pos, len, remap_flags | REMAP_FILE_DEDUP);
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out_drop_write:
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mnt_drop_write_file(dst_file);
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return ret;
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}
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EXPORT_SYMBOL(vfs_dedupe_file_range_one);
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int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
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{
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struct file_dedupe_range_info *info;
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struct inode *src = file_inode(file);
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u64 off;
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u64 len;
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int i;
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int ret;
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u16 count = same->dest_count;
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loff_t deduped;
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if (!(file->f_mode & FMODE_READ))
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return -EINVAL;
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|
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if (same->reserved1 || same->reserved2)
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return -EINVAL;
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off = same->src_offset;
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len = same->src_length;
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if (S_ISDIR(src->i_mode))
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return -EISDIR;
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if (!S_ISREG(src->i_mode))
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return -EINVAL;
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|
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if (!file->f_op->remap_file_range)
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return -EOPNOTSUPP;
|
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ret = remap_verify_area(file, off, len, false);
|
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if (ret < 0)
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return ret;
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ret = 0;
|
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|
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if (off + len > i_size_read(src))
|
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return -EINVAL;
|
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|
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/* Arbitrary 1G limit on a single dedupe request, can be raised. */
|
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len = min_t(u64, len, 1 << 30);
|
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|
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/* pre-format output fields to sane values */
|
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for (i = 0; i < count; i++) {
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same->info[i].bytes_deduped = 0ULL;
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same->info[i].status = FILE_DEDUPE_RANGE_SAME;
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}
|
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|
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for (i = 0, info = same->info; i < count; i++, info++) {
|
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struct fd dst_fd = fdget(info->dest_fd);
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struct file *dst_file = dst_fd.file;
|
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|
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if (!dst_file) {
|
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info->status = -EBADF;
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goto next_loop;
|
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}
|
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|
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if (info->reserved) {
|
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info->status = -EINVAL;
|
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goto next_fdput;
|
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}
|
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|
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deduped = vfs_dedupe_file_range_one(file, off, dst_file,
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info->dest_offset, len,
|
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REMAP_FILE_CAN_SHORTEN);
|
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if (deduped == -EBADE)
|
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info->status = FILE_DEDUPE_RANGE_DIFFERS;
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else if (deduped < 0)
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info->status = deduped;
|
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else
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info->bytes_deduped = len;
|
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|
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next_fdput:
|
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fdput(dst_fd);
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next_loop:
|
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if (fatal_signal_pending(current))
|
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break;
|
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}
|
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return ret;
|
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}
|
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EXPORT_SYMBOL(vfs_dedupe_file_range);
|
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|
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480
fs/remap_range.c
480
fs/remap_range.c
@ -26,9 +26,9 @@
|
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* Returns appropriate error code that caller should return or
|
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* zero in case the clone should be allowed.
|
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*/
|
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int generic_remap_checks(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t *req_count, unsigned int remap_flags)
|
||||
static int generic_remap_checks(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t *req_count, unsigned int remap_flags)
|
||||
{
|
||||
struct inode *inode_in = file_in->f_mapping->host;
|
||||
struct inode *inode_out = file_out->f_mapping->host;
|
||||
@ -95,3 +95,477 @@ int generic_remap_checks(struct file *file_in, loff_t pos_in,
|
||||
*req_count = count;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int remap_verify_area(struct file *file, loff_t pos, loff_t len,
|
||||
bool write)
|
||||
{
|
||||
struct inode *inode = file_inode(file);
|
||||
|
||||
if (unlikely(pos < 0 || len < 0))
|
||||
return -EINVAL;
|
||||
|
||||
if (unlikely((loff_t) (pos + len) < 0))
|
||||
return -EINVAL;
|
||||
|
||||
if (unlikely(inode->i_flctx && mandatory_lock(inode))) {
|
||||
loff_t end = len ? pos + len - 1 : OFFSET_MAX;
|
||||
int retval;
|
||||
|
||||
retval = locks_mandatory_area(inode, file, pos, end,
|
||||
write ? F_WRLCK : F_RDLCK);
|
||||
if (retval < 0)
|
||||
return retval;
|
||||
}
|
||||
|
||||
return security_file_permission(file, write ? MAY_WRITE : MAY_READ);
|
||||
}
|
||||
|
||||
/*
|
||||
* Ensure that we don't remap a partial EOF block in the middle of something
|
||||
* else. Assume that the offsets have already been checked for block
|
||||
* alignment.
|
||||
*
|
||||
* For clone we only link a partial EOF block above or at the destination file's
|
||||
* EOF. For deduplication we accept a partial EOF block only if it ends at the
|
||||
* destination file's EOF (can not link it into the middle of a file).
|
||||
*
|
||||
* Shorten the request if possible.
|
||||
*/
|
||||
static int generic_remap_check_len(struct inode *inode_in,
|
||||
struct inode *inode_out,
|
||||
loff_t pos_out,
|
||||
loff_t *len,
|
||||
unsigned int remap_flags)
|
||||
{
|
||||
u64 blkmask = i_blocksize(inode_in) - 1;
|
||||
loff_t new_len = *len;
|
||||
|
||||
if ((*len & blkmask) == 0)
|
||||
return 0;
|
||||
|
||||
if (pos_out + *len < i_size_read(inode_out))
|
||||
new_len &= ~blkmask;
|
||||
|
||||
if (new_len == *len)
|
||||
return 0;
|
||||
|
||||
if (remap_flags & REMAP_FILE_CAN_SHORTEN) {
|
||||
*len = new_len;
|
||||
return 0;
|
||||
}
|
||||
|
||||
return (remap_flags & REMAP_FILE_DEDUP) ? -EBADE : -EINVAL;
|
||||
}
|
||||
|
||||
/* Read a page's worth of file data into the page cache. */
|
||||
static struct page *vfs_dedupe_get_page(struct inode *inode, loff_t offset)
|
||||
{
|
||||
struct page *page;
|
||||
|
||||
page = read_mapping_page(inode->i_mapping, offset >> PAGE_SHIFT, NULL);
|
||||
if (IS_ERR(page))
|
||||
return page;
|
||||
if (!PageUptodate(page)) {
|
||||
put_page(page);
|
||||
return ERR_PTR(-EIO);
|
||||
}
|
||||
return page;
|
||||
}
|
||||
|
||||
/*
|
||||
* Lock two pages, ensuring that we lock in offset order if the pages are from
|
||||
* the same file.
|
||||
*/
|
||||
static void vfs_lock_two_pages(struct page *page1, struct page *page2)
|
||||
{
|
||||
/* Always lock in order of increasing index. */
|
||||
if (page1->index > page2->index)
|
||||
swap(page1, page2);
|
||||
|
||||
lock_page(page1);
|
||||
if (page1 != page2)
|
||||
lock_page(page2);
|
||||
}
|
||||
|
||||
/* Unlock two pages, being careful not to unlock the same page twice. */
|
||||
static void vfs_unlock_two_pages(struct page *page1, struct page *page2)
|
||||
{
|
||||
unlock_page(page1);
|
||||
if (page1 != page2)
|
||||
unlock_page(page2);
|
||||
}
|
||||
|
||||
/*
|
||||
* Compare extents of two files to see if they are the same.
|
||||
* Caller must have locked both inodes to prevent write races.
|
||||
*/
|
||||
static int vfs_dedupe_file_range_compare(struct inode *src, loff_t srcoff,
|
||||
struct inode *dest, loff_t destoff,
|
||||
loff_t len, bool *is_same)
|
||||
{
|
||||
loff_t src_poff;
|
||||
loff_t dest_poff;
|
||||
void *src_addr;
|
||||
void *dest_addr;
|
||||
struct page *src_page;
|
||||
struct page *dest_page;
|
||||
loff_t cmp_len;
|
||||
bool same;
|
||||
int error;
|
||||
|
||||
error = -EINVAL;
|
||||
same = true;
|
||||
while (len) {
|
||||
src_poff = srcoff & (PAGE_SIZE - 1);
|
||||
dest_poff = destoff & (PAGE_SIZE - 1);
|
||||
cmp_len = min(PAGE_SIZE - src_poff,
|
||||
PAGE_SIZE - dest_poff);
|
||||
cmp_len = min(cmp_len, len);
|
||||
if (cmp_len <= 0)
|
||||
goto out_error;
|
||||
|
||||
src_page = vfs_dedupe_get_page(src, srcoff);
|
||||
if (IS_ERR(src_page)) {
|
||||
error = PTR_ERR(src_page);
|
||||
goto out_error;
|
||||
}
|
||||
dest_page = vfs_dedupe_get_page(dest, destoff);
|
||||
if (IS_ERR(dest_page)) {
|
||||
error = PTR_ERR(dest_page);
|
||||
put_page(src_page);
|
||||
goto out_error;
|
||||
}
|
||||
|
||||
vfs_lock_two_pages(src_page, dest_page);
|
||||
|
||||
/*
|
||||
* Now that we've locked both pages, make sure they're still
|
||||
* mapped to the file data we're interested in. If not,
|
||||
* someone is invalidating pages on us and we lose.
|
||||
*/
|
||||
if (!PageUptodate(src_page) || !PageUptodate(dest_page) ||
|
||||
src_page->mapping != src->i_mapping ||
|
||||
dest_page->mapping != dest->i_mapping) {
|
||||
same = false;
|
||||
goto unlock;
|
||||
}
|
||||
|
||||
src_addr = kmap_atomic(src_page);
|
||||
dest_addr = kmap_atomic(dest_page);
|
||||
|
||||
flush_dcache_page(src_page);
|
||||
flush_dcache_page(dest_page);
|
||||
|
||||
if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
|
||||
same = false;
|
||||
|
||||
kunmap_atomic(dest_addr);
|
||||
kunmap_atomic(src_addr);
|
||||
unlock:
|
||||
vfs_unlock_two_pages(src_page, dest_page);
|
||||
put_page(dest_page);
|
||||
put_page(src_page);
|
||||
|
||||
if (!same)
|
||||
break;
|
||||
|
||||
srcoff += cmp_len;
|
||||
destoff += cmp_len;
|
||||
len -= cmp_len;
|
||||
}
|
||||
|
||||
*is_same = same;
|
||||
return 0;
|
||||
|
||||
out_error:
|
||||
return error;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check that the two inodes are eligible for cloning, the ranges make
|
||||
* sense, and then flush all dirty data. Caller must ensure that the
|
||||
* inodes have been locked against any other modifications.
|
||||
*
|
||||
* If there's an error, then the usual negative error code is returned.
|
||||
* Otherwise returns 0 with *len set to the request length.
|
||||
*/
|
||||
int generic_remap_file_range_prep(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t *len, unsigned int remap_flags)
|
||||
{
|
||||
struct inode *inode_in = file_inode(file_in);
|
||||
struct inode *inode_out = file_inode(file_out);
|
||||
bool same_inode = (inode_in == inode_out);
|
||||
int ret;
|
||||
|
||||
/* Don't touch certain kinds of inodes */
|
||||
if (IS_IMMUTABLE(inode_out))
|
||||
return -EPERM;
|
||||
|
||||
if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
|
||||
return -ETXTBSY;
|
||||
|
||||
/* Don't reflink dirs, pipes, sockets... */
|
||||
if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
|
||||
return -EISDIR;
|
||||
if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
|
||||
return -EINVAL;
|
||||
|
||||
/* Zero length dedupe exits immediately; reflink goes to EOF. */
|
||||
if (*len == 0) {
|
||||
loff_t isize = i_size_read(inode_in);
|
||||
|
||||
if ((remap_flags & REMAP_FILE_DEDUP) || pos_in == isize)
|
||||
return 0;
|
||||
if (pos_in > isize)
|
||||
return -EINVAL;
|
||||
*len = isize - pos_in;
|
||||
if (*len == 0)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Check that we don't violate system file offset limits. */
|
||||
ret = generic_remap_checks(file_in, pos_in, file_out, pos_out, len,
|
||||
remap_flags);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/* Wait for the completion of any pending IOs on both files */
|
||||
inode_dio_wait(inode_in);
|
||||
if (!same_inode)
|
||||
inode_dio_wait(inode_out);
|
||||
|
||||
ret = filemap_write_and_wait_range(inode_in->i_mapping,
|
||||
pos_in, pos_in + *len - 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = filemap_write_and_wait_range(inode_out->i_mapping,
|
||||
pos_out, pos_out + *len - 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/*
|
||||
* Check that the extents are the same.
|
||||
*/
|
||||
if (remap_flags & REMAP_FILE_DEDUP) {
|
||||
bool is_same = false;
|
||||
|
||||
ret = vfs_dedupe_file_range_compare(inode_in, pos_in,
|
||||
inode_out, pos_out, *len, &is_same);
|
||||
if (ret)
|
||||
return ret;
|
||||
if (!is_same)
|
||||
return -EBADE;
|
||||
}
|
||||
|
||||
ret = generic_remap_check_len(inode_in, inode_out, pos_out, len,
|
||||
remap_flags);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/* If can't alter the file contents, we're done. */
|
||||
if (!(remap_flags & REMAP_FILE_DEDUP))
|
||||
ret = file_modified(file_out);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(generic_remap_file_range_prep);
|
||||
|
||||
loff_t do_clone_file_range(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t len, unsigned int remap_flags)
|
||||
{
|
||||
loff_t ret;
|
||||
|
||||
WARN_ON_ONCE(remap_flags & REMAP_FILE_DEDUP);
|
||||
|
||||
/*
|
||||
* FICLONE/FICLONERANGE ioctls enforce that src and dest files are on
|
||||
* the same mount. Practically, they only need to be on the same file
|
||||
* system.
|
||||
*/
|
||||
if (file_inode(file_in)->i_sb != file_inode(file_out)->i_sb)
|
||||
return -EXDEV;
|
||||
|
||||
ret = generic_file_rw_checks(file_in, file_out);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
if (!file_in->f_op->remap_file_range)
|
||||
return -EOPNOTSUPP;
|
||||
|
||||
ret = remap_verify_area(file_in, pos_in, len, false);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = remap_verify_area(file_out, pos_out, len, true);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = file_in->f_op->remap_file_range(file_in, pos_in,
|
||||
file_out, pos_out, len, remap_flags);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
|
||||
fsnotify_access(file_in);
|
||||
fsnotify_modify(file_out);
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(do_clone_file_range);
|
||||
|
||||
loff_t vfs_clone_file_range(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t len, unsigned int remap_flags)
|
||||
{
|
||||
loff_t ret;
|
||||
|
||||
file_start_write(file_out);
|
||||
ret = do_clone_file_range(file_in, pos_in, file_out, pos_out, len,
|
||||
remap_flags);
|
||||
file_end_write(file_out);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(vfs_clone_file_range);
|
||||
|
||||
/* Check whether we are allowed to dedupe the destination file */
|
||||
static bool allow_file_dedupe(struct file *file)
|
||||
{
|
||||
if (capable(CAP_SYS_ADMIN))
|
||||
return true;
|
||||
if (file->f_mode & FMODE_WRITE)
|
||||
return true;
|
||||
if (uid_eq(current_fsuid(), file_inode(file)->i_uid))
|
||||
return true;
|
||||
if (!inode_permission(file_inode(file), MAY_WRITE))
|
||||
return true;
|
||||
return false;
|
||||
}
|
||||
|
||||
loff_t vfs_dedupe_file_range_one(struct file *src_file, loff_t src_pos,
|
||||
struct file *dst_file, loff_t dst_pos,
|
||||
loff_t len, unsigned int remap_flags)
|
||||
{
|
||||
loff_t ret;
|
||||
|
||||
WARN_ON_ONCE(remap_flags & ~(REMAP_FILE_DEDUP |
|
||||
REMAP_FILE_CAN_SHORTEN));
|
||||
|
||||
ret = mnt_want_write_file(dst_file);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = remap_verify_area(dst_file, dst_pos, len, true);
|
||||
if (ret < 0)
|
||||
goto out_drop_write;
|
||||
|
||||
ret = -EPERM;
|
||||
if (!allow_file_dedupe(dst_file))
|
||||
goto out_drop_write;
|
||||
|
||||
ret = -EXDEV;
|
||||
if (src_file->f_path.mnt != dst_file->f_path.mnt)
|
||||
goto out_drop_write;
|
||||
|
||||
ret = -EISDIR;
|
||||
if (S_ISDIR(file_inode(dst_file)->i_mode))
|
||||
goto out_drop_write;
|
||||
|
||||
ret = -EINVAL;
|
||||
if (!dst_file->f_op->remap_file_range)
|
||||
goto out_drop_write;
|
||||
|
||||
if (len == 0) {
|
||||
ret = 0;
|
||||
goto out_drop_write;
|
||||
}
|
||||
|
||||
ret = dst_file->f_op->remap_file_range(src_file, src_pos, dst_file,
|
||||
dst_pos, len, remap_flags | REMAP_FILE_DEDUP);
|
||||
out_drop_write:
|
||||
mnt_drop_write_file(dst_file);
|
||||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(vfs_dedupe_file_range_one);
|
||||
|
||||
int vfs_dedupe_file_range(struct file *file, struct file_dedupe_range *same)
|
||||
{
|
||||
struct file_dedupe_range_info *info;
|
||||
struct inode *src = file_inode(file);
|
||||
u64 off;
|
||||
u64 len;
|
||||
int i;
|
||||
int ret;
|
||||
u16 count = same->dest_count;
|
||||
loff_t deduped;
|
||||
|
||||
if (!(file->f_mode & FMODE_READ))
|
||||
return -EINVAL;
|
||||
|
||||
if (same->reserved1 || same->reserved2)
|
||||
return -EINVAL;
|
||||
|
||||
off = same->src_offset;
|
||||
len = same->src_length;
|
||||
|
||||
if (S_ISDIR(src->i_mode))
|
||||
return -EISDIR;
|
||||
|
||||
if (!S_ISREG(src->i_mode))
|
||||
return -EINVAL;
|
||||
|
||||
if (!file->f_op->remap_file_range)
|
||||
return -EOPNOTSUPP;
|
||||
|
||||
ret = remap_verify_area(file, off, len, false);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
ret = 0;
|
||||
|
||||
if (off + len > i_size_read(src))
|
||||
return -EINVAL;
|
||||
|
||||
/* Arbitrary 1G limit on a single dedupe request, can be raised. */
|
||||
len = min_t(u64, len, 1 << 30);
|
||||
|
||||
/* pre-format output fields to sane values */
|
||||
for (i = 0; i < count; i++) {
|
||||
same->info[i].bytes_deduped = 0ULL;
|
||||
same->info[i].status = FILE_DEDUPE_RANGE_SAME;
|
||||
}
|
||||
|
||||
for (i = 0, info = same->info; i < count; i++, info++) {
|
||||
struct fd dst_fd = fdget(info->dest_fd);
|
||||
struct file *dst_file = dst_fd.file;
|
||||
|
||||
if (!dst_file) {
|
||||
info->status = -EBADF;
|
||||
goto next_loop;
|
||||
}
|
||||
|
||||
if (info->reserved) {
|
||||
info->status = -EINVAL;
|
||||
goto next_fdput;
|
||||
}
|
||||
|
||||
deduped = vfs_dedupe_file_range_one(file, off, dst_file,
|
||||
info->dest_offset, len,
|
||||
REMAP_FILE_CAN_SHORTEN);
|
||||
if (deduped == -EBADE)
|
||||
info->status = FILE_DEDUPE_RANGE_DIFFERS;
|
||||
else if (deduped < 0)
|
||||
info->status = deduped;
|
||||
else
|
||||
info->bytes_deduped = len;
|
||||
|
||||
next_fdput:
|
||||
fdput(dst_fd);
|
||||
next_loop:
|
||||
if (fatal_signal_pending(current))
|
||||
break;
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(vfs_dedupe_file_range);
|
||||
|
||||
@ -3009,9 +3009,6 @@ extern int sb_min_blocksize(struct super_block *, int);
|
||||
extern int generic_file_mmap(struct file *, struct vm_area_struct *);
|
||||
extern int generic_file_readonly_mmap(struct file *, struct vm_area_struct *);
|
||||
extern ssize_t generic_write_checks(struct kiocb *, struct iov_iter *);
|
||||
extern int generic_remap_checks(struct file *file_in, loff_t pos_in,
|
||||
struct file *file_out, loff_t pos_out,
|
||||
loff_t *count, unsigned int remap_flags);
|
||||
extern int generic_write_check_limits(struct file *file, loff_t pos,
|
||||
loff_t *count);
|
||||
extern int generic_file_rw_checks(struct file *file_in, struct file *file_out);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user