1 files changed, 276 insertions, 118 deletions

diff --git a/fs/smb/client/file.c b/fs/smb/client/file.c
index 1374635e89fa..7ff5cc9c5c5b 100644
--- a/fs/smb/client/file.c
+++ b/fs/smb/client/file.c
@@ -9,6 +9,7 @@
  *
  */
 #include <linux/fs.h>
+#include <linux/fs_struct.h>
 #include <linux/filelock.h>
 #include <linux/backing-dev.h>
 #include <linux/stat.h>
@@ -49,8 +50,10 @@ static void cifs_prepare_write(struct netfs_io_subrequest *subreq)
 	struct cifs_io_subrequest *wdata =
 		container_of(subreq, struct cifs_io_subrequest, subreq);
 	struct cifs_io_request *req = wdata->req;
+	struct netfs_io_stream *stream = &req->rreq.io_streams[subreq->stream_nr];
 	struct TCP_Server_Info *server;
 	struct cifsFileInfo *open_file = req->cfile;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(wdata->rreq->inode->i_sb);
 	size_t wsize = req->rreq.wsize;
 	int rc;
 
@@ -62,6 +65,10 @@ static void cifs_prepare_write(struct netfs_io_subrequest *subreq)
 	server = cifs_pick_channel(tlink_tcon(open_file->tlink)->ses);
 	wdata->server = server;
 
+	if (cifs_sb->ctx->wsize == 0)
+		cifs_negotiate_wsize(server, cifs_sb->ctx,
+				     tlink_tcon(req->cfile->tlink));
+
 retry:
 	if (open_file->invalidHandle) {
 		rc = cifs_reopen_file(open_file, false);
@@ -73,16 +80,30 @@ retry:
 		}
 	}
 
-	rc = server->ops->wait_mtu_credits(server, wsize, &wdata->subreq.max_len,
+	rc = server->ops->wait_mtu_credits(server, wsize, &stream->sreq_max_len,
 					   &wdata->credits);
 	if (rc < 0) {
 		subreq->error = rc;
 		return netfs_prepare_write_failed(subreq);
 	}
 
+	wdata->credits.rreq_debug_id = subreq->rreq->debug_id;
+	wdata->credits.rreq_debug_index = subreq->debug_index;
+	wdata->credits.in_flight_check = 1;
+	trace_smb3_rw_credits(wdata->rreq->debug_id,
+			      wdata->subreq.debug_index,
+			      wdata->credits.value,
+			      server->credits, server->in_flight,
+			      wdata->credits.value,
+			      cifs_trace_rw_credits_write_prepare);
+
 #ifdef CONFIG_CIFS_SMB_DIRECT
-	if (server->smbd_conn)
-		subreq->max_nr_segs = server->smbd_conn->max_frmr_depth;
+	if (server->smbd_conn) {
+		const struct smbdirect_socket_parameters *sp =
+			smbd_get_parameters(server->smbd_conn);
+
+		stream->sreq_max_segs = sp->max_frmr_depth;
+	}
 #endif
 }
 
@@ -97,11 +118,11 @@ static void cifs_issue_write(struct netfs_io_subrequest *subreq)
 	int rc;
 
 	if (cifs_forced_shutdown(sbi)) {
-		rc = -EIO;
+		rc = smb_EIO(smb_eio_trace_forced_shutdown);
 		goto fail;
 	}
 
-	rc = adjust_credits(wdata->server, &wdata->credits, wdata->subreq.len);
+	rc = adjust_credits(wdata->server, wdata, cifs_trace_rw_credits_issue_write_adjust);
 	if (rc)
 		goto fail;
 
@@ -119,51 +140,66 @@ fail:
 	else
 		trace_netfs_sreq(subreq, netfs_sreq_trace_fail);
 	add_credits_and_wake_if(wdata->server, &wdata->credits, 0);
-	cifs_write_subrequest_terminated(wdata, rc, false);
+	cifs_write_subrequest_terminated(wdata, rc);
 	goto out;
 }
 
+static void cifs_netfs_invalidate_cache(struct netfs_io_request *wreq)
+{
+	cifs_invalidate_cache(wreq->inode, 0);
+}
+
 /*
- * Split the read up according to how many credits we can get for each piece.
- * It's okay to sleep here if we need to wait for more credit to become
- * available.
- *
- * We also choose the server and allocate an operation ID to be cleaned up
- * later.
+ * Negotiate the size of a read operation on behalf of the netfs library.
  */
-static bool cifs_clamp_length(struct netfs_io_subrequest *subreq)
+static int cifs_prepare_read(struct netfs_io_subrequest *subreq)
 {
 	struct netfs_io_request *rreq = subreq->rreq;
 	struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq);
 	struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq);
-	struct TCP_Server_Info *server = req->server;
+	struct TCP_Server_Info *server;
 	struct cifs_sb_info *cifs_sb = CIFS_SB(rreq->inode->i_sb);
-	size_t rsize = 0;
-	int rc;
+	size_t size;
+	int rc = 0;
+
+	if (!rdata->have_xid) {
+		rdata->xid = get_xid();
+		rdata->have_xid = true;
+	}
 
-	rdata->xid = get_xid();
-	rdata->have_xid = true;
+	server = cifs_pick_channel(tlink_tcon(req->cfile->tlink)->ses);
 	rdata->server = server;
 
 	if (cifs_sb->ctx->rsize == 0)
-		cifs_sb->ctx->rsize =
-			server->ops->negotiate_rsize(tlink_tcon(req->cfile->tlink),
-						     cifs_sb->ctx);
+		cifs_negotiate_rsize(server, cifs_sb->ctx,
+				     tlink_tcon(req->cfile->tlink));
 
+	rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize,
+					   &size, &rdata->credits);
+	if (rc)
+		return rc;
 
-	rc = server->ops->wait_mtu_credits(server, cifs_sb->ctx->rsize, &rsize,
-					   &rdata->credits);
-	if (rc) {
-		subreq->error = rc;
-		return false;
-	}
+	rreq->io_streams[0].sreq_max_len = size;
+
+	rdata->credits.in_flight_check = 1;
+	rdata->credits.rreq_debug_id = rreq->debug_id;
+	rdata->credits.rreq_debug_index = subreq->debug_index;
+
+	trace_smb3_rw_credits(rdata->rreq->debug_id,
+			      rdata->subreq.debug_index,
+			      rdata->credits.value,
+			      server->credits, server->in_flight, 0,
+			      cifs_trace_rw_credits_read_submit);
 
-	subreq->len = min_t(size_t, subreq->len, rsize);
 #ifdef CONFIG_CIFS_SMB_DIRECT
-	if (server->smbd_conn)
-		subreq->max_nr_segs = server->smbd_conn->max_frmr_depth;
+	if (server->smbd_conn) {
+		const struct smbdirect_socket_parameters *sp =
+			smbd_get_parameters(server->smbd_conn);
+
+		rreq->io_streams[0].sreq_max_segs = sp->max_frmr_depth;
+	}
 #endif
-	return true;
+	return 0;
 }
 
 /*
@@ -172,31 +208,43 @@ static bool cifs_clamp_length(struct netfs_io_subrequest *subreq)
  * to only read a portion of that, but as long as we read something, the netfs
  * helper will call us again so that we can issue another read.
  */
-static void cifs_req_issue_read(struct netfs_io_subrequest *subreq)
+static void cifs_issue_read(struct netfs_io_subrequest *subreq)
 {
 	struct netfs_io_request *rreq = subreq->rreq;
 	struct cifs_io_subrequest *rdata = container_of(subreq, struct cifs_io_subrequest, subreq);
 	struct cifs_io_request *req = container_of(subreq->rreq, struct cifs_io_request, rreq);
+	struct TCP_Server_Info *server = rdata->server;
 	int rc = 0;
 
 	cifs_dbg(FYI, "%s: op=%08x[%x] mapping=%p len=%zu/%zu\n",
 		 __func__, rreq->debug_id, subreq->debug_index, rreq->mapping,
 		 subreq->transferred, subreq->len);
 
+	rc = adjust_credits(server, rdata, cifs_trace_rw_credits_issue_read_adjust);
+	if (rc)
+		goto failed;
+
 	if (req->cfile->invalidHandle) {
 		do {
 			rc = cifs_reopen_file(req->cfile, true);
 		} while (rc == -EAGAIN);
 		if (rc)
-			goto out;
+			goto failed;
 	}
 
-	__set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
+	if (subreq->rreq->origin != NETFS_UNBUFFERED_READ &&
+	    subreq->rreq->origin != NETFS_DIO_READ)
+		__set_bit(NETFS_SREQ_CLEAR_TAIL, &subreq->flags);
 
+	trace_netfs_sreq(subreq, netfs_sreq_trace_submit);
 	rc = rdata->server->ops->async_readv(rdata);
-out:
 	if (rc)
-		netfs_subreq_terminated(subreq, rc, false);
+		goto failed;
+	return;
+
+failed:
+	subreq->error = rc;
+	netfs_read_subreq_terminated(subreq);
 }
 
 /*
@@ -234,12 +282,11 @@ static int cifs_init_request(struct netfs_io_request *rreq, struct file *file)
 		open_file = file->private_data;
 		rreq->netfs_priv = file->private_data;
 		req->cfile = cifsFileInfo_get(open_file);
-		req->server = cifs_pick_channel(tlink_tcon(req->cfile->tlink)->ses);
 		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RWPIDFORWARD)
 			req->pid = req->cfile->pid;
 	} else if (rreq->origin != NETFS_WRITEBACK) {
 		WARN_ON_ONCE(1);
-		return -EIO;
+		return smb_EIO1(smb_eio_trace_not_netfs_writeback, rreq->origin);
 	}
 
 	return 0;
@@ -260,12 +307,6 @@ static void cifs_rreq_done(struct netfs_io_request *rreq)
 		inode_set_atime_to_ts(inode, inode_get_mtime(inode));
 }
 
-static void cifs_post_modify(struct inode *inode)
-{
-	/* Indication to update ctime and mtime as close is deferred */
-	set_bit(CIFS_INO_MODIFIED_ATTR, &CIFS_I(inode)->flags);
-}
-
 static void cifs_free_request(struct netfs_io_request *rreq)
 {
 	struct cifs_io_request *req = container_of(rreq, struct cifs_io_request, rreq);
@@ -289,7 +330,20 @@ static void cifs_free_subrequest(struct netfs_io_subrequest *subreq)
 #endif
 	}
 
-	add_credits_and_wake_if(rdata->server, &rdata->credits, 0);
+	if (rdata->credits.value != 0) {
+		trace_smb3_rw_credits(rdata->rreq->debug_id,
+				      rdata->subreq.debug_index,
+				      rdata->credits.value,
+				      rdata->server ? rdata->server->credits : 0,
+				      rdata->server ? rdata->server->in_flight : 0,
+				      -rdata->credits.value,
+				      cifs_trace_rw_credits_free_subreq);
+		if (rdata->server)
+			add_credits_and_wake_if(rdata->server, &rdata->credits, 0);
+		else
+			rdata->credits.value = 0;
+	}
+
 	if (rdata->have_xid)
 		free_xid(rdata->xid);
 }
@@ -300,13 +354,13 @@ const struct netfs_request_ops cifs_req_ops = {
 	.init_request		= cifs_init_request,
 	.free_request		= cifs_free_request,
 	.free_subrequest	= cifs_free_subrequest,
-	.clamp_length		= cifs_clamp_length,
-	.issue_read		= cifs_req_issue_read,
+	.prepare_read		= cifs_prepare_read,
+	.issue_read		= cifs_issue_read,
 	.done			= cifs_rreq_done,
-	.post_modify		= cifs_post_modify,
 	.begin_writeback	= cifs_begin_writeback,
 	.prepare_write		= cifs_prepare_write,
 	.issue_write		= cifs_issue_write,
+	.invalidate_cache	= cifs_netfs_invalidate_cache,
 };
 
 /*
@@ -348,7 +402,7 @@ cifs_mark_open_files_invalid(struct cifs_tcon *tcon)
 	spin_unlock(&tcon->tc_lock);
 
 	/*
-	 * BB Add call to invalidate_inodes(sb) for all superblocks mounted
+	 * BB Add call to evict_inodes(sb) for all superblocks mounted
 	 * to this tcon.
 	 */
 }
@@ -899,6 +953,66 @@ void _cifsFileInfo_put(struct cifsFileInfo *cifs_file,
 	}
 }
 
+int cifs_file_flush(const unsigned int xid, struct inode *inode,
+		    struct cifsFileInfo *cfile)
+{
+	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+	struct cifs_tcon *tcon;
+	int rc;
+
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)
+		return 0;
+
+	if (cfile && (OPEN_FMODE(cfile->f_flags) & FMODE_WRITE)) {
+		tcon = tlink_tcon(cfile->tlink);
+		return tcon->ses->server->ops->flush(xid, tcon,
+						     &cfile->fid);
+	}
+	rc = cifs_get_writable_file(CIFS_I(inode), FIND_WR_ANY, &cfile);
+	if (!rc) {
+		tcon = tlink_tcon(cfile->tlink);
+		rc = tcon->ses->server->ops->flush(xid, tcon, &cfile->fid);
+		cifsFileInfo_put(cfile);
+	} else if (rc == -EBADF) {
+		rc = 0;
+	}
+	return rc;
+}
+
+static int cifs_do_truncate(const unsigned int xid, struct dentry *dentry)
+{
+	struct cifsInodeInfo *cinode = CIFS_I(d_inode(dentry));
+	struct inode *inode = d_inode(dentry);
+	struct cifsFileInfo *cfile = NULL;
+	struct TCP_Server_Info *server;
+	struct cifs_tcon *tcon;
+	int rc;
+
+	rc = filemap_write_and_wait(inode->i_mapping);
+	if (is_interrupt_error(rc))
+		return -ERESTARTSYS;
+	mapping_set_error(inode->i_mapping, rc);
+
+	cfile = find_writable_file(cinode, FIND_WR_FSUID_ONLY);
+	rc = cifs_file_flush(xid, inode, cfile);
+	if (!rc) {
+		if (cfile) {
+			tcon = tlink_tcon(cfile->tlink);
+			server = tcon->ses->server;
+			rc = server->ops->set_file_size(xid, tcon,
+							cfile, 0, false);
+		}
+		if (!rc) {
+			netfs_resize_file(&cinode->netfs, 0, true);
+			cifs_setsize(inode, 0);
+			inode->i_blocks = 0;
+		}
+	}
+	if (cfile)
+		cifsFileInfo_put(cfile);
+	return rc;
+}
+
 int cifs_open(struct inode *inode, struct file *file)
 
 {
@@ -922,7 +1036,7 @@ int cifs_open(struct inode *inode, struct file *file)
 	cifs_sb = CIFS_SB(inode->i_sb);
 	if (unlikely(cifs_forced_shutdown(cifs_sb))) {
 		free_xid(xid);
-		return -EIO;
+		return smb_EIO(smb_eio_trace_forced_shutdown);
 	}
 
 	tlink = cifs_sb_tlink(cifs_sb);
@@ -951,18 +1065,39 @@ int cifs_open(struct inode *inode, struct file *file)
 			file->f_op = &cifs_file_direct_ops;
 	}
 
+	if (file->f_flags & O_TRUNC) {
+		rc = cifs_do_truncate(xid, file_dentry(file));
+		if (rc)
+			goto out;
+	}
+
 	/* Get the cached handle as SMB2 close is deferred */
-	rc = cifs_get_readable_path(tcon, full_path, &cfile);
+	if (OPEN_FMODE(file->f_flags) & FMODE_WRITE) {
+		rc = cifs_get_writable_path(tcon, full_path,
+					    FIND_WR_FSUID_ONLY |
+					    FIND_WR_NO_PENDING_DELETE,
+					    &cfile);
+	} else {
+		rc = cifs_get_readable_path(tcon, full_path, &cfile);
+	}
 	if (rc == 0) {
-		if (file->f_flags == cfile->f_flags) {
+		unsigned int oflags = file->f_flags & ~(O_CREAT|O_EXCL|O_TRUNC);
+		unsigned int cflags = cfile->f_flags & ~(O_CREAT|O_EXCL|O_TRUNC);
+
+		if (cifs_convert_flags(oflags, 0) == cifs_convert_flags(cflags, 0) &&
+		    (oflags & (O_SYNC|O_DIRECT)) == (cflags & (O_SYNC|O_DIRECT))) {
 			file->private_data = cfile;
 			spin_lock(&CIFS_I(inode)->deferred_lock);
 			cifs_del_deferred_close(cfile);
 			spin_unlock(&CIFS_I(inode)->deferred_lock);
 			goto use_cache;
-		} else {
-			_cifsFileInfo_put(cfile, true, false);
 		}
+		_cifsFileInfo_put(cfile, true, false);
+	} else {
+		/* hard link on the defeered close file */
+		rc = cifs_get_hardlink_path(tcon, inode, file);
+		if (rc)
+			cifs_close_deferred_file(CIFS_I(inode));
 	}
 
 	if (server->oplocks)
@@ -1326,7 +1461,7 @@ int cifs_close(struct inode *inode, struct file *file)
 		dclose = kmalloc(sizeof(struct cifs_deferred_close), GFP_KERNEL);
 		if ((cfile->status_file_deleted == false) &&
 		    (smb2_can_defer_close(inode, dclose))) {
-			if (test_and_clear_bit(CIFS_INO_MODIFIED_ATTR, &cinode->flags)) {
+			if (test_and_clear_bit(NETFS_ICTX_MODIFIED_ATTR, &cinode->netfs.flags)) {
 				inode_set_mtime_to_ts(inode,
 						      inode_set_ctime_current(inode));
 			}
@@ -1365,7 +1500,7 @@ void
 cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
 {
 	struct cifsFileInfo *open_file, *tmp;
-	struct list_head tmp_list;
+	LIST_HEAD(tmp_list);
 
 	if (!tcon->use_persistent || !tcon->need_reopen_files)
 		return;
@@ -1373,7 +1508,6 @@ cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
 	tcon->need_reopen_files = false;
 
 	cifs_dbg(FYI, "Reopen persistent handles\n");
-	INIT_LIST_HEAD(&tmp_list);
 
 	/* list all files open on tree connection, reopen resilient handles  */
 	spin_lock(&tcon->open_file_lock);
@@ -2028,6 +2162,29 @@ cifs_move_llist(struct list_head *source, struct list_head *dest)
 		list_move(li, dest);
 }
 
+int
+cifs_get_hardlink_path(struct cifs_tcon *tcon, struct inode *inode,
+				struct file *file)
+{
+	struct cifsFileInfo *open_file = NULL;
+	struct cifsInodeInfo *cinode = CIFS_I(inode);
+	int rc = 0;
+
+	spin_lock(&tcon->open_file_lock);
+	spin_lock(&cinode->open_file_lock);
+
+	list_for_each_entry(open_file, &cinode->openFileList, flist) {
+		if (file->f_flags == open_file->f_flags) {
+			rc = -EINVAL;
+			break;
+		}
+	}
+
+	spin_unlock(&cinode->open_file_lock);
+	spin_unlock(&tcon->open_file_lock);
+	return rc;
+}
+
 void
 cifs_free_llist(struct list_head *llist)
 {
@@ -2056,9 +2213,7 @@ cifs_unlock_range(struct cifsFileInfo *cfile, struct file_lock *flock,
 	struct cifsInodeInfo *cinode = CIFS_I(d_inode(cfile->dentry));
 	struct cifsLockInfo *li, *tmp;
 	__u64 length = cifs_flock_len(flock);
-	struct list_head tmp_llist;
-
-	INIT_LIST_HEAD(&tmp_llist);
+	LIST_HEAD(tmp_llist);
 
 	/*
 	 * Accessing maxBuf is racy with cifs_reconnect - need to store value
@@ -2354,20 +2509,24 @@ int cifs_lock(struct file *file, int cmd, struct file_lock *flock)
 	return rc;
 }
 
-void cifs_write_subrequest_terminated(struct cifs_io_subrequest *wdata, ssize_t result,
-				      bool was_async)
+void cifs_write_subrequest_terminated(struct cifs_io_subrequest *wdata, ssize_t result)
 {
 	struct netfs_io_request *wreq = wdata->rreq;
-	loff_t new_server_eof;
+	struct netfs_inode *ictx = netfs_inode(wreq->inode);
+	loff_t wrend;
 
 	if (result > 0) {
-		new_server_eof = wdata->subreq.start + wdata->subreq.transferred + result;
+		wrend = wdata->subreq.start + wdata->subreq.transferred + result;
 
-		if (new_server_eof > netfs_inode(wreq->inode)->remote_i_size)
-			netfs_resize_file(netfs_inode(wreq->inode), new_server_eof, true);
+		if (wrend > ictx->zero_point &&
+		    (wdata->rreq->origin == NETFS_UNBUFFERED_WRITE ||
+		     wdata->rreq->origin == NETFS_DIO_WRITE))
+			ictx->zero_point = wrend;
+		if (wrend > ictx->remote_i_size)
+			netfs_resize_file(ictx, wrend, true);
 	}
 
-	netfs_write_subrequest_terminated(&wdata->subreq, result, was_async);
+	netfs_write_subrequest_terminated(&wdata->subreq, result);
 }
 
 struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode,
@@ -2449,6 +2608,9 @@ refind_writable:
 			continue;
 		if (with_delete && !(open_file->fid.access & DELETE))
 			continue;
+		if ((flags & FIND_WR_NO_PENDING_DELETE) &&
+		    open_file->status_file_deleted)
+			continue;
 		if (OPEN_FMODE(open_file->f_flags) & FMODE_WRITE) {
 			if (!open_file->invalidHandle) {
 				/* found a good writable file */
@@ -2462,7 +2624,7 @@ refind_writable:
 			}
 		}
 	}
-	/* couldn't find useable FH with same pid, try any available */
+	/* couldn't find usable FH with same pid, try any available */
 	if (!any_available) {
 		any_available = true;
 		goto refind_writable;
@@ -2566,6 +2728,16 @@ cifs_get_readable_path(struct cifs_tcon *tcon, const char *name,
 		spin_unlock(&tcon->open_file_lock);
 		free_dentry_path(page);
 		*ret_file = find_readable_file(cinode, 0);
+		if (*ret_file) {
+			spin_lock(&cinode->open_file_lock);
+			if ((*ret_file)->status_file_deleted) {
+				spin_unlock(&cinode->open_file_lock);
+				cifsFileInfo_put(*ret_file);
+				*ret_file = NULL;
+			} else {
+				spin_unlock(&cinode->open_file_lock);
+			}
+		}
 		return *ret_file ? 0 : -ENOENT;
 	}
 
@@ -2580,13 +2752,10 @@ cifs_get_readable_path(struct cifs_tcon *tcon, const char *name,
 int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
 		      int datasync)
 {
-	unsigned int xid;
-	int rc = 0;
-	struct cifs_tcon *tcon;
-	struct TCP_Server_Info *server;
 	struct cifsFileInfo *smbfile = file->private_data;
 	struct inode *inode = file_inode(file);
-	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+	unsigned int xid;
+	int rc;
 
 	rc = file_write_and_wait_range(file, start, end);
 	if (rc) {
@@ -2594,39 +2763,15 @@ int cifs_strict_fsync(struct file *file, loff_t start, loff_t end,
 		return rc;
 	}
 
-	xid = get_xid();
-
-	cifs_dbg(FYI, "Sync file - name: %pD datasync: 0x%x\n",
-		 file, datasync);
+	cifs_dbg(FYI, "%s: name=%pD datasync=0x%x\n", __func__, file, datasync);
 
 	if (!CIFS_CACHE_READ(CIFS_I(inode))) {
 		rc = cifs_zap_mapping(inode);
-		if (rc) {
-			cifs_dbg(FYI, "rc: %d during invalidate phase\n", rc);
-			rc = 0; /* don't care about it in fsync */
-		}
+		cifs_dbg(FYI, "%s: invalidate mapping: rc = %d\n", __func__, rc);
 	}
 
-	tcon = tlink_tcon(smbfile->tlink);
-	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOSSYNC)) {
-		server = tcon->ses->server;
-		if (server->ops->flush == NULL) {
-			rc = -ENOSYS;
-			goto strict_fsync_exit;
-		}
-
-		if ((OPEN_FMODE(smbfile->f_flags) & FMODE_WRITE) == 0) {
-			smbfile = find_writable_file(CIFS_I(inode), FIND_WR_ANY);
-			if (smbfile) {
-				rc = server->ops->flush(xid, tcon, &smbfile->fid);
-				cifsFileInfo_put(smbfile);
-			} else
-				cifs_dbg(FYI, "ignore fsync for file not open for write\n");
-		} else
-			rc = server->ops->flush(xid, tcon, &smbfile->fid);
-	}
-
-strict_fsync_exit:
+	xid = get_xid();
+	rc = cifs_file_flush(xid, inode, smbfile);
 	free_xid(xid);
 	return rc;
 }
@@ -2708,6 +2853,7 @@ cifs_writev(struct kiocb *iocb, struct iov_iter *from)
 	struct inode *inode = file->f_mapping->host;
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
 	struct TCP_Server_Info *server = tlink_tcon(cfile->tlink)->ses->server;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 	ssize_t rc;
 
 	rc = netfs_start_io_write(inode);
@@ -2724,12 +2870,16 @@ cifs_writev(struct kiocb *iocb, struct iov_iter *from)
 	if (rc <= 0)
 		goto out;
 
-	if (!cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
+	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) &&
+	    (cifs_find_lock_conflict(cfile, iocb->ki_pos, iov_iter_count(from),
 				     server->vals->exclusive_lock_type, 0,
-				     NULL, CIFS_WRITE_OP))
-		rc = netfs_buffered_write_iter_locked(iocb, from, NULL);
-	else
+				     NULL, CIFS_WRITE_OP))) {
 		rc = -EACCES;
+		goto out;
+	}
+
+	rc = netfs_buffered_write_iter_locked(iocb, from, NULL);
+
 out:
 	up_read(&cinode->lock_sem);
 	netfs_end_io_write(inode);
@@ -2861,9 +3011,7 @@ cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
 	if (!CIFS_CACHE_READ(cinode))
 		return netfs_unbuffered_read_iter(iocb, to);
 
-	if (cap_unix(tcon->ses) &&
-	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
-	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0)) {
+	if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) {
 		if (iocb->ki_flags & IOCB_DIRECT)
 			return netfs_unbuffered_read_iter(iocb, to);
 		return netfs_buffered_read_iter(iocb, to);
@@ -2877,6 +3025,7 @@ cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
 		rc = netfs_start_io_direct(inode);
 		if (rc < 0)
 			goto out;
+		rc = -EACCES;
 		down_read(&cinode->lock_sem);
 		if (!cifs_find_lock_conflict(
 			    cfile, iocb->ki_pos, iov_iter_count(to),
@@ -2889,6 +3038,7 @@ cifs_strict_readv(struct kiocb *iocb, struct iov_iter *to)
 		rc = netfs_start_io_read(inode);
 		if (rc < 0)
 			goto out;
+		rc = -EACCES;
 		down_read(&cinode->lock_sem);
 		if (!cifs_find_lock_conflict(
 			    cfile, iocb->ki_pos, iov_iter_count(to),
@@ -2913,38 +3063,38 @@ static const struct vm_operations_struct cifs_file_vm_ops = {
 	.page_mkwrite = cifs_page_mkwrite,
 };
 
-int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma)
+int cifs_file_strict_mmap_prepare(struct vm_area_desc *desc)
 {
 	int xid, rc = 0;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = file_inode(desc->file);
 
 	xid = get_xid();
 
 	if (!CIFS_CACHE_READ(CIFS_I(inode)))
 		rc = cifs_zap_mapping(inode);
 	if (!rc)
-		rc = generic_file_mmap(file, vma);
+		rc = generic_file_mmap_prepare(desc);
 	if (!rc)
-		vma->vm_ops = &cifs_file_vm_ops;
+		desc->vm_ops = &cifs_file_vm_ops;
 
 	free_xid(xid);
 	return rc;
 }
 
-int cifs_file_mmap(struct file *file, struct vm_area_struct *vma)
+int cifs_file_mmap_prepare(struct vm_area_desc *desc)
 {
 	int rc, xid;
 
 	xid = get_xid();
 
-	rc = cifs_revalidate_file(file);
+	rc = cifs_revalidate_file(desc->file);
 	if (rc)
 		cifs_dbg(FYI, "Validation prior to mmap failed, error=%d\n",
 			 rc);
 	if (!rc)
-		rc = generic_file_mmap(file, vma);
+		rc = generic_file_mmap_prepare(desc);
 	if (!rc)
-		vma->vm_ops = &cifs_file_vm_ops;
+		desc->vm_ops = &cifs_file_vm_ops;
 
 	free_xid(xid);
 	return rc;
@@ -3002,7 +3152,8 @@ void cifs_oplock_break(struct work_struct *work)
 	struct cifsFileInfo *cfile = container_of(work, struct cifsFileInfo,
 						  oplock_break);
 	struct inode *inode = d_inode(cfile->dentry);
-	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
+	struct super_block *sb = inode->i_sb;
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
 	struct cifs_tcon *tcon;
 	struct TCP_Server_Info *server;
@@ -3012,6 +3163,12 @@ void cifs_oplock_break(struct work_struct *work)
 	__u64 persistent_fid, volatile_fid;
 	__u16 net_fid;
 
+	/*
+	 * Hold a reference to the superblock to prevent it and its inodes from
+	 * being freed while we are accessing cinode. Otherwise, _cifsFileInfo_put()
+	 * may release the last reference to the sb and trigger inode eviction.
+	 */
+	cifs_sb_active(sb);
 	wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS,
 			TASK_UNINTERRUPTIBLE);
 
@@ -3031,7 +3188,7 @@ void cifs_oplock_break(struct work_struct *work)
 		cinode->oplock = 0;
 	}
 
-	if (inode && S_ISREG(inode->i_mode)) {
+	if (S_ISREG(inode->i_mode)) {
 		if (CIFS_CACHE_READ(cinode))
 			break_lease(inode, O_RDONLY);
 		else
@@ -3084,6 +3241,7 @@ oplock_break_ack:
 	cifs_put_tlink(tlink);
 out:
 	cifs_done_oplock_break(cinode);
+	cifs_sb_deactive(sb);
 }
 
 static int cifs_swap_activate(struct swap_info_struct *sis,