Commit 7b9b9edb authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French
Browse files

CIFS: Do not reset lease state to NONE on lease break 



Currently on lease break the client sets a caching level twice:
when oplock is detected and when oplock is processed. While the
1st attempt sets the level to the value provided by the server,
the 2nd one resets the level to None unconditionally.
This happens because the oplock/lease processing code was changed
to avoid races between page cache flushes and oplock breaks.
The commit c11f1df5 ("cifs: Wait for writebacks to complete
before attempting write.") fixed the races for oplocks but didn't
apply the same changes for leases resulting in overwriting the
server granted value to None. Fix this by properly processing
lease breaks.

Signed-off-by: default avatarPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
parent d26e2903

fs/cifs/smb2misc.c

+14 −3
Original line number Diff line number Diff line
@@ -517,7 +517,6 @@ smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp, 
	__u8 lease_state;

	struct list_head *tmp;

	struct cifsFileInfo *cfile;

	struct TCP_Server_Info *server = tcon->ses->server;

	struct cifs_pending_open *open;

	struct cifsInodeInfo *cinode;

	int ack_req = le32_to_cpu(rsp->Flags &
@@ -537,13 +536,25 @@ smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp, 
		cifs_dbg(FYI, "lease key match, lease break 0x%x\n",

			 le32_to_cpu(rsp->NewLeaseState));



		server->ops->set_oplock_level(cinode, lease_state, 0, NULL);



		if (ack_req)

			cfile->oplock_break_cancelled = false;

		else

			cfile->oplock_break_cancelled = true;



		set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);



		/*

		 * Set or clear flags depending on the lease state being READ.

		 * HANDLE caching flag should be added when the client starts

		 * to defer closing remote file handles with HANDLE leases.

		 */

		if (lease_state & SMB2_LEASE_READ_CACHING_HE)

			set_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,

				&cinode->flags);

		else

			clear_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,

				  &cinode->flags);



		queue_work(cifsoplockd_wq, &cfile->oplock_break);

		kfree(lw);

		return true;

fs/cifs/smb2ops.c

+12 −3
Original line number Diff line number Diff line
@@ -2604,6 +2604,15 @@ smb2_downgrade_oplock(struct TCP_Server_Info *server, 
		server->ops->set_oplock_level(cinode, 0, 0, NULL);

}



static void

smb21_downgrade_oplock(struct TCP_Server_Info *server,

		       struct cifsInodeInfo *cinode, bool set_level2)

{

	server->ops->set_oplock_level(cinode,

				      set_level2 ? SMB2_LEASE_READ_CACHING_HE :

				      0, 0, NULL);

}



static void

smb2_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock,

		      unsigned int epoch, bool *purge_cache)
@@ -3656,7 +3665,7 @@ struct smb_version_operations smb21_operations = { 
	.print_stats = smb2_print_stats,

	.is_oplock_break = smb2_is_valid_oplock_break,

	.handle_cancelled_mid = smb2_handle_cancelled_mid,

	.downgrade_oplock = smb2_downgrade_oplock,

	.downgrade_oplock = smb21_downgrade_oplock,

	.need_neg = smb2_need_neg,

	.negotiate = smb2_negotiate,

	.negotiate_wsize = smb2_negotiate_wsize,
@@ -3753,7 +3762,7 @@ struct smb_version_operations smb30_operations = { 
	.dump_share_caps = smb2_dump_share_caps,

	.is_oplock_break = smb2_is_valid_oplock_break,

	.handle_cancelled_mid = smb2_handle_cancelled_mid,

	.downgrade_oplock = smb2_downgrade_oplock,

	.downgrade_oplock = smb21_downgrade_oplock,

	.need_neg = smb2_need_neg,

	.negotiate = smb2_negotiate,

	.negotiate_wsize = smb3_negotiate_wsize,
@@ -3858,7 +3867,7 @@ struct smb_version_operations smb311_operations = { 
	.dump_share_caps = smb2_dump_share_caps,

	.is_oplock_break = smb2_is_valid_oplock_break,

	.handle_cancelled_mid = smb2_handle_cancelled_mid,

	.downgrade_oplock = smb2_downgrade_oplock,

	.downgrade_oplock = smb21_downgrade_oplock,

	.need_neg = smb2_need_neg,

	.negotiate = smb2_negotiate,

	.negotiate_wsize = smb3_negotiate_wsize,

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