[PATCH v3 57/59] cifs: Remove some code that's no longer used, part 2

David Howells
2023-12-07T21:27:03Z

Remove some code that was #if'd out with the netfslib conversion. This is
split into parts for file.c as the diff generator otherwise produces a hard
to read diff for part of it where a big chunk is cut out.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: Rohith Surabattula <rohiths.msft@gmail.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-cifs@vger.kernel.org
cc: linux-cachefs@redhat.com
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org
---
fs/smb/client/file.c | 694 +------------------------------------------
1 file changed, 1 insertion(+), 693 deletions(-)

diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c
index d3cb65e3234b..7e51c2702cdb 100644
--- a/fs/smb/client/file.c
+++ b/fs/smb/client/file.c
@@ -2561,699 +2561,6 @@ cifs_get_readable_path(struct cifs_tcon *tcon, const char *name,
return -ENOENT;
}

-#if 0 // TODO remove 2773
-void
-cifs_writedata_release(struct cifs_io_subrequest *wdata)
-{
- if (wdata->uncached)
- kref_put(&wdata->ctx->refcount, cifs_aio_ctx_release);
-#ifdef CONFIG_CIFS_SMB_DIRECT
- if (wdata->mr) {
- smbd_deregister_mr(wdata->mr);
- wdata->mr = NULL;
- }
-#endif
-
- if (wdata->cfile)
- cifsFileInfo_put(wdata->cfile);
-
- kfree(wdata);
-}
-
-/*
- * Write failed with a retryable error. Resend the write request. It's also
- * possible that the page was redirtied so re-clean the page.
- */
-static void
-cifs_writev_requeue(struct cifs_io_subrequest *wdata)
-{
- int rc = 0;
- struct inode *inode = d_inode(wdata->cfile->dentry);
- struct TCP_Server_Info *server;
- unsigned int rest_len = wdata->subreq.len;
- loff_t fpos = wdata->subreq.start;
-
- server = tlink_tcon(wdata->cfile->tlink)->ses->server;
- do {
- struct cifs_io_subrequest *wdata2;
- unsigned int wsize, cur_len;
-
- wsize = server->ops->wp_retry_size(inode);
- if (wsize < rest_len) {
- if (wsize < PAGE_SIZE) {
- rc = -EOPNOTSUPP;
- break;
- }
- cur_len = min(round_down(wsize, PAGE_SIZE), rest_len);
- } else {
- cur_len = rest_len;
- }
-
- wdata2 = cifs_writedata_alloc(cifs_writev_complete);
- if (!wdata2) {
- rc = -ENOMEM;
- break;
- }
-
- wdata2->sync_mode = wdata->sync_mode;
- wdata2->subreq.start = fpos;
- wdata2->subreq.len = cur_len;
- wdata2->subreq.io_iter = wdata->subreq.io_iter;
-
- iov_iter_advance(&wdata2->subreq.io_iter, fpos - wdata->subreq.start);
- iov_iter_truncate(&wdata2->subreq.io_iter, wdata2->subreq.len);
-
- if (iov_iter_is_xarray(&wdata2->subreq.io_iter))
- /* Check for pages having been redirtied and clean
- * them. We can do this by walking the xarray. If
- * it's not an xarray, then it's a DIO and we shouldn't
- * be mucking around with the page bits.
- */
- cifs_undirty_folios(inode, fpos, cur_len);
-
- rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY,
- &wdata2->cfile);
- if (!wdata2->cfile) {
- cifs_dbg(VFS, "No writable handle to retry writepages rc=%d\n",
- rc);
- if (!is_retryable_error(rc))
- rc = -EBADF;
- } else {
- wdata2->pid = wdata2->cfile->pid;
- rc = server->ops->async_writev(wdata2);
- }
-
- cifs_put_writedata(wdata2);
- if (rc) {
- if (is_retryable_error(rc))
- continue;
- fpos += cur_len;
- rest_len -= cur_len;
- break;
- }
-
- fpos += cur_len;
- rest_len -= cur_len;
- } while (rest_len > 0);
-
- /* Clean up remaining pages from the original wdata */
- if (iov_iter_is_xarray(&wdata->subreq.io_iter))
- cifs_pages_write_failed(inode, fpos, rest_len);
-
- if (rc != 0 && !is_retryable_error(rc))
- mapping_set_error(inode->i_mapping, rc);
- cifs_put_writedata(wdata);
-}
-
-void
-cifs_writev_complete(struct work_struct *work)
-{
- struct cifs_io_subrequest *wdata = container_of(work,
- struct cifs_io_subrequest, work);
- struct inode *inode = d_inode(wdata->cfile->dentry);
-
- if (wdata->result == 0) {
- spin_lock(&inode->i_lock);
- cifs_update_eof(CIFS_I(inode), wdata->subreq.start, wdata->subreq.len);
- spin_unlock(&inode->i_lock);
- cifs_stats_bytes_written(tlink_tcon(wdata->cfile->tlink),
- wdata->subreq.len);
- } else if (wdata->sync_mode == WB_SYNC_ALL && wdata->result == -EAGAIN)
- return cifs_writev_requeue(wdata);
-
- if (wdata->result == -EAGAIN)
- cifs_pages_write_redirty(inode, wdata->subreq.start, wdata->subreq.len);
- else if (wdata->result < 0)
- cifs_pages_write_failed(inode, wdata->subreq.start, wdata->subreq.len);
- else
- cifs_pages_written_back(inode, wdata->subreq.start, wdata->subreq.len);
-
- if (wdata->result != -EAGAIN)
- mapping_set_error(inode->i_mapping, wdata->result);
- cifs_put_writedata(wdata);
-}
-
-struct cifs_io_subrequest *cifs_writedata_alloc(work_func_t complete)
-{
- struct cifs_io_subrequest *wdata;
-
- wdata = kzalloc(sizeof(*wdata), GFP_NOFS);
- if (wdata != NULL) {
- refcount_set(&wdata->subreq.ref, 1);
- INIT_LIST_HEAD(&wdata->list);
- init_completion(&wdata->done);
- INIT_WORK(&wdata->work, complete);
- }
- return wdata;
-}
-
-static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
-{
- struct address_space *mapping = page->mapping;
- loff_t offset = (loff_t)page->index << PAGE_SHIFT;
- char *write_data;
- int rc = -EFAULT;
- int bytes_written = 0;
- struct inode *inode;
- struct cifsFileInfo *open_file;
-
- if (!mapping || !mapping->host)
- return -EFAULT;
-
- inode = page->mapping->host;
-
- offset += (loff_t)from;
- write_data = kmap(page);
- write_data += from;
-
- if ((to > PAGE_SIZE) || (from > to)) {
- kunmap(page);
- return -EIO;
- }
-
- /* racing with truncate? */
- if (offset > mapping->host->i_size) {
- kunmap(page);
- return 0; /* don't care */
- }
-
- /* check to make sure that we are not extending the file */
- if (mapping->host->i_size - offset < (loff_t)to)
- to = (unsigned)(mapping->host->i_size - offset);
-
- rc = cifs_get_writable_file(CIFS_I(mapping->host), FIND_WR_ANY,
- &open_file);
- if (!rc) {
- bytes_written = cifs_write(open_file, open_file->pid,
- write_data, to - from, &offset);
- cifsFileInfo_put(open_file);
- /* Does mm or vfs already set times? */
- simple_inode_init_ts(inode);
- if ((bytes_written > 0) && (offset))
- rc = 0;
- else if (bytes_written < 0)
- rc = bytes_written;
- else
- rc = -EFAULT;
- } else {
- cifs_dbg(FYI, "No writable handle for write page rc=%d\n", rc);
- if (!is_retryable_error(rc))
- rc = -EIO;
- }
-
- kunmap(page);
- return rc;
-}
-
-/*
- * Extend the region to be written back to include subsequent contiguously
- * dirty pages if possible, but don't sleep while doing so.
- */
-static void cifs_extend_writeback(struct address_space *mapping,
- long *_count,
- loff_t start,
- int max_pages,
- size_t max_len,
- unsigned int *_len)
-{
- struct folio_batch batch;
- struct folio *folio;
- unsigned int psize, nr_pages;
- size_t len = *_len;
- pgoff_t index = (start + len) / PAGE_SIZE;
- bool stop = true;
- unsigned int i;
- XA_STATE(xas, &mapping->i_pages, index);
-
- folio_batch_init(&batch);
-
- do {
- /* Firstly, we gather up a batch of contiguous dirty pages
- * under the RCU read lock - but we can't clear the dirty flags
- * there if any of those pages are mapped.
- */
- rcu_read_lock();
-
- xas_for_each(&xas, folio, ULONG_MAX) {
- stop = true;
- if (xas_retry(&xas, folio))
- continue;
- if (xa_is_value(folio))
- break;
- if (folio_index(folio) != index)
- break;
- if (!folio_try_get_rcu(folio)) {
- xas_reset(&xas);
- continue;
- }
- nr_pages = folio_nr_pages(folio);
- if (nr_pages > max_pages)
- break;
-
- /* Has the page moved or been split? */
- if (unlikely(folio != xas_reload(&xas))) {
- folio_put(folio);
- break;
- }
-
- if (!folio_trylock(folio)) {
- folio_put(folio);
- break;
- }
- if (!folio_test_dirty(folio) || folio_test_writeback(folio)) {
- folio_unlock(folio);
- folio_put(folio);
- break;
- }
-
- max_pages -= nr_pages;
- psize = folio_size(folio);
- len += psize;
- stop = false;
- if (max_pages <= 0 || len >= max_len || *_count <= 0)
- stop = true;
-
- index += nr_pages;
- if (!folio_batch_add(&batch, folio))
- break;
- if (stop)
- break;
- }
-
- if (!stop)
- xas_pause(&xas);
- rcu_read_unlock();
-
- /* Now, if we obtained any pages, we can shift them to being
- * writable and mark them for caching.
- */
- if (!folio_batch_count(&batch))
- break;
-
- for (i = 0; i < folio_batch_count(&batch); i++) {
- folio = batch.folios[i];
- /* The folio should be locked, dirty and not undergoing
- * writeback from the loop above.
- */
- if (!folio_clear_dirty_for_io(folio))
- WARN_ON(1);
- folio_start_writeback(folio);
-
- *_count -= folio_nr_pages(folio);
- folio_unlock(folio);
- }
-
- folio_batch_release(&batch);
- cond_resched();
- } while (!stop);
-
- *_len = len;
-}
-
-/*
- * Write back the locked page and any subsequent non-locked dirty pages.
- */
-static ssize_t cifs_write_back_from_locked_folio(struct address_space *mapping,
- struct writeback_control *wbc,
- struct folio *folio,
- loff_t start, loff_t end)
-{
- struct inode *inode = mapping->host;
- struct TCP_Server_Info *server;
- struct cifs_io_subrequest *wdata;
- struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
- struct cifs_credits credits_on_stack;
- struct cifs_credits *credits = &credits_on_stack;
- struct cifsFileInfo *cfile = NULL;
- unsigned int xid, len;
- loff_t i_size = i_size_read(inode);
- size_t max_len, wsize;
- long count = wbc->nr_to_write;
- int rc;
-
- /* The folio should be locked, dirty and not undergoing writeback. */
- folio_start_writeback(folio);
-
- count -= folio_nr_pages(folio);
- len = folio_size(folio);
-
- xid = get_xid();
- server = cifs_pick_channel(cifs_sb_master_tcon(cifs_sb)->ses);
-
- rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
- if (rc) {
- cifs_dbg(VFS, "No writable handle in writepages rc=%d\n", rc);
- goto err_xid;
- }
-
- rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->wsize,
- &wsize, credits);
- if (rc != 0)
- goto err_close;
-
- wdata = cifs_writedata_alloc(cifs_writev_complete);
- if (!wdata) {
- rc = -ENOMEM;
- goto err_uncredit;
- }
-
- wdata->sync_mode = wbc->sync_mode;
- wdata->subreq.start = folio_pos(folio);
- wdata->pid = cfile->pid;
- wdata->credits = credits_on_stack;
- wdata->cfile = cfile;
- wdata->server = server;
- cfile = NULL;
-
- /* Find all consecutive lockable dirty pages, stopping when we find a
- * page that is not immediately lockable, is not dirty or is missing,
- * or we reach the end of the range.
- */
- if (start < i_size) {
- /* Trim the write to the EOF; the extra data is ignored. Also
- * put an upper limit on the size of a single storedata op.
- */
- max_len = wsize;
- max_len = min_t(unsigned long long, max_len, end - start + 1);
- max_len = min_t(unsigned long long, max_len, i_size - start);
-
- if (len < max_len) {
- int max_pages = INT_MAX;
-
-#ifdef CONFIG_CIFS_SMB_DIRECT
- if (server->smbd_conn)
- max_pages = server->smbd_conn->max_frmr_depth;
-#endif
- max_pages -= folio_nr_pages(folio);
-
- if (max_pages > 0)
- cifs_extend_writeback(mapping, &count, start,
- max_pages, max_len, &len);
- }
- len = min_t(loff_t, len, max_len);
- }
-
- wdata->subreq.len = len;
-
- /* We now have a contiguous set of dirty pages, each with writeback
- * set; the first page is still locked at this point, but all the rest
- * have been unlocked.
- */
- folio_unlock(folio);
-
- if (start < i_size) {
- iov_iter_xarray(&wdata->subreq.io_iter, ITER_SOURCE, &mapping->i_pages,
- start, len);
-
- rc = adjust_credits(wdata->server, &wdata->credits, wdata->subreq.len);
- if (rc)
- goto err_wdata;
-
- if (wdata->cfile->invalidHandle)
- rc = -EAGAIN;
- else
- rc = wdata->server->ops->async_writev(wdata);
- if (rc >= 0) {
- cifs_put_writedata(wdata);
- goto err_close;
- }
- } else {
- /* The dirty region was entirely beyond the EOF. */
- cifs_pages_written_back(inode, start, len);
- rc = 0;
- }
-
-err_wdata:
- cifs_put_writedata(wdata);
-err_uncredit:
- add_credits_and_wake_if(server, credits, 0);
-err_close:
- if (cfile)
- cifsFileInfo_put(cfile);
-err_xid:
- free_xid(xid);
- if (rc == 0) {
- wbc->nr_to_write = count;
- rc = len;
- } else if (is_retryable_error(rc)) {
- cifs_pages_write_redirty(inode, start, len);
- } else {
- cifs_pages_write_failed(inode, start, len);
- mapping_set_error(mapping, rc);
- }
- /* Indication to update ctime and mtime as close is deferred */
- set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
- return rc;
-}
-
-/*
- * write a region of pages back to the server
- */
-static int cifs_writepages_region(struct address_space *mapping,
- struct writeback_control *wbc,
- loff_t start, loff_t end, loff_t *_next)
-{
- struct folio_batch fbatch;
- int skips = 0;
-
- folio_batch_init(&fbatch);
- do {
- int nr;
- pgoff_t index = start / PAGE_SIZE;
-
- nr = filemap_get_folios_tag(mapping, &index, end / PAGE_SIZE,
- PAGECACHE_TAG_DIRTY, &fbatch);
- if (!nr)
- break;
-
- for (int i = 0; i < nr; i++) {
- ssize_t ret;
- struct folio *folio = fbatch.folios[i];
-
-redo_folio:
- start = folio_pos(folio); /* May regress with THPs */
-
- /* At this point we hold neither the i_pages lock nor the
- * page lock: the page may be truncated or invalidated
- * (changing page->mapping to NULL), or even swizzled
- * back from swapper_space to tmpfs file mapping
- */
- if (wbc->sync_mode != WB_SYNC_NONE) {
- ret = folio_lock_killable(folio);
- if (ret < 0)
- goto write_error;
- } else {
- if (!folio_trylock(folio))
- goto skip_write;
- }
-
- if (folio_mapping(folio) != mapping ||
- !folio_test_dirty(folio)) {
- start += folio_size(folio);
- folio_unlock(folio);
- continue;
- }
-
- if (folio_test_writeback(folio) ||
- folio_test_fscache(folio)) {
- folio_unlock(folio);
- if (wbc->sync_mode == WB_SYNC_NONE)
- goto skip_write;
-
- folio_wait_writeback(folio);
-#ifdef CONFIG_CIFS_FSCACHE
- folio_wait_fscache(folio);
-#endif
- goto redo_folio;
- }
-
- if (!folio_clear_dirty_for_io(folio))
- /* We hold the page lock - it should've been dirty. */
- WARN_ON(1);
-
- ret = cifs_write_back_from_locked_folio(mapping, wbc, folio, start, end);
- if (ret < 0)
- goto write_error;
-
- start += ret;
- continue;
-
-write_error:
- folio_batch_release(&fbatch);
- *_next = start;
- return ret;
-
-skip_write:
- /*
- * Too many skipped writes, or need to reschedule?
- * Treat it as a write error without an error code.
- */
- if (skips >= 5 || need_resched()) {
- ret = 0;
- goto write_error;
- }
-
- /* Otherwise, just skip that folio and go on to the next */
- skips++;
- start += folio_size(folio);
- continue;
- }
-
- folio_batch_release(&fbatch);
- cond_resched();
- } while (wbc->nr_to_write > 0);
-
- *_next = start;
- return 0;
-}
-
-/*
- * Write some of the pending data back to the server
- */
-static int cifs_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
-{
- loff_t start, next;
- int ret;
-
- /* We have to be careful as we can end up racing with setattr()
- * truncating the pagecache since the caller doesn't take a lock here
- * to prevent it.
- */
-
- if (wbc->range_cyclic) {
- start = mapping->writeback_index * PAGE_SIZE;
- ret = cifs_writepages_region(mapping, wbc, start, LLONG_MAX, &next);
- if (ret == 0) {
- mapping->writeback_index = next / PAGE_SIZE;
- if (start > 0 && wbc->nr_to_write > 0) {
- ret = cifs_writepages_region(mapping, wbc, 0,
- start, &next);
- if (ret == 0)
- mapping->writeback_index =
- next / PAGE_SIZE;
- }
- }
- } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) {
- ret = cifs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next);
- if (wbc->nr_to_write > 0 && ret == 0)
- mapping->writeback_index = next / PAGE_SIZE;
- } else {
- ret = cifs_writepages_region(mapping, wbc,
- wbc->range_start, wbc->range_end, &next);
- }
-
- return ret;
-}
-
-static int
-cifs_writepage_locked(struct page *page, struct writeback_control *wbc)
-{
- int rc;
- unsigned int xid;
-
- xid = get_xid();
-/* BB add check for wbc flags */
- get_page(page);
- if (!PageUptodate(page))
- cifs_dbg(FYI, "ppw - page not up to date\n");
-
- /*
- * Set the "writeback" flag, and clear "dirty" in the radix tree.
- *
- * A writepage() implementation always needs to do either this,
- * or re-dirty the page with "redirty_page_for_writepage()" in
- * the case of a failure.
- *
- * Just unlocking the page will cause the radix tree tag-bits
- * to fail to update with the state of the page correctly.
- */
- set_page_writeback(page);
-retry_write:
- rc = cifs_partialpagewrite(page, 0, PAGE_SIZE);
- if (is_retryable_error(rc)) {
- if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN)
- goto retry_write;
- redirty_page_for_writepage(wbc, page);
- } else if (rc != 0) {
- SetPageError(page);
- mapping_set_error(page->mapping, rc);
- } else {
- SetPageUptodate(page);
- }
- end_page_writeback(page);
- put_page(page);
- free_xid(xid);
- return rc;
-}
-
-static int cifs_write_end(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned copied,
- struct page *page, void *fsdata)
-{
- int rc;
- struct inode *inode = mapping->host;
- struct cifsFileInfo *cfile = file->private_data;
- struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
- struct folio *folio = page_folio(page);
- __u32 pid;
-
- if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
- pid = cfile->pid;
- else
- pid = current->tgid;
-
- cifs_dbg(FYI, "write_end for page %p from pos %lld with %d bytes\n",
- page, pos, copied);
-
- if (folio_test_checked(folio)) {
- if (copied == len)
- folio_mark_uptodate(folio);
- folio_clear_checked(folio);
- } else if (!folio_test_uptodate(folio) && copied == PAGE_SIZE)
- folio_mark_uptodate(folio);
-
- if (!folio_test_uptodate(folio)) {
- char *page_data;
- unsigned offset = pos & (PAGE_SIZE - 1);
- unsigned int xid;
-
- xid = get_xid();
- /* this is probably better than directly calling
- partialpage_write since in this function the file handle is
- known which we might as well leverage */
- /* BB check if anything else missing out of ppw
- such as updating last write time */
- page_data = kmap(page);
- rc = cifs_write(cfile, pid, page_data + offset, copied, &pos);
- /* if (rc < 0) should we set writebehind rc? */
- kunmap(page);
-
- free_xid(xid);
- } else {
- rc = copied;
- pos += copied;
- set_page_dirty(page);
- }
-
- if (rc > 0) {
- spin_lock(&inode->i_lock);
- if (pos > inode->i_size) {
- i_size_write(inode, pos);
- inode->i_blocks = (512 - 1 + pos) >> 9;
- }
- spin_unlock(&inode->i_lock);
- }
-
- unlock_page(page);
- put_page(page);
- /* Indication to update ctime and mtime as close is deferred */
- set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
-
- return rc;
-}
-#endif // End netfs removal 2773
-
/*
* Flush data on a strict file.
*/
@@ -4568,6 +3875,7 @@ cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
}
#endif // end netfslib remove 4633

+
static vm_fault_t cifs_page_mkwrite(struct vm_fault *vmf)
{
return netfs_page_mkwrite(vmf, NULL);