From b56eae4df9ef922d5785ec4a15d54d9527cedb13 Mon Sep 17 00:00:00 2001 From: Steve French Date: Tue, 3 Nov 2015 09:26:27 -0600 Subject: [SMB3] Send durable handle v2 contexts when use of persistent handles required Version 2 of the patch. Thanks to Dan Carpenter and the smatch tool for finding a problem in the first version of this patch. CC: Dan Carpenter Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French --- fs/cifs/smb2pdu.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 121 insertions(+), 2 deletions(-) (limited to 'fs/cifs/smb2pdu.c') diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 597a417ba94d..2520ed5ded48 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -1151,13 +1151,130 @@ add_lease_context(struct TCP_Server_Info *server, struct kvec *iov, return 0; } +static struct create_durable_v2 * +create_durable_v2_buf(struct cifs_fid *pfid) +{ + struct create_durable_v2 *buf; + + buf = kzalloc(sizeof(struct create_durable_v2), GFP_KERNEL); + if (!buf) + return NULL; + + buf->ccontext.DataOffset = cpu_to_le16(offsetof + (struct create_durable_v2, dcontext)); + buf->ccontext.DataLength = cpu_to_le32(sizeof(struct durable_context_v2)); + buf->ccontext.NameOffset = cpu_to_le16(offsetof + (struct create_durable_v2, Name)); + buf->ccontext.NameLength = cpu_to_le16(4); + + buf->dcontext.Timeout = 0; /* Should this be configurable by workload */ + buf->dcontext.Flags = cpu_to_le32(SMB2_DHANDLE_FLAG_PERSISTENT); + get_random_bytes(buf->dcontext.CreateGuid, 16); + memcpy(pfid->create_guid, buf->dcontext.CreateGuid, 16); + + /* SMB2_CREATE_DURABLE_HANDLE_REQUEST is "DH2Q" */ + buf->Name[0] = 'D'; + buf->Name[1] = 'H'; + buf->Name[2] = '2'; + buf->Name[3] = 'Q'; + return buf; +} + +static struct create_durable_handle_reconnect_v2 * +create_reconnect_durable_v2_buf(struct cifs_fid *fid) +{ + struct create_durable_handle_reconnect_v2 *buf; + + buf = kzalloc(sizeof(struct create_durable_handle_reconnect_v2), + GFP_KERNEL); + if (!buf) + return NULL; + + buf->ccontext.DataOffset = + cpu_to_le16(offsetof(struct create_durable_handle_reconnect_v2, + dcontext)); + buf->ccontext.DataLength = + cpu_to_le32(sizeof(struct durable_reconnect_context_v2)); + buf->ccontext.NameOffset = + cpu_to_le16(offsetof(struct create_durable_handle_reconnect_v2, + Name)); + buf->ccontext.NameLength = cpu_to_le16(4); + + buf->dcontext.Fid.PersistentFileId = fid->persistent_fid; + buf->dcontext.Fid.VolatileFileId = fid->volatile_fid; + buf->dcontext.Flags = cpu_to_le32(SMB2_DHANDLE_FLAG_PERSISTENT); + memcpy(buf->dcontext.CreateGuid, fid->create_guid, 16); + + /* SMB2_CREATE_DURABLE_HANDLE_RECONNECT_V2 is "DH2C" */ + buf->Name[0] = 'D'; + buf->Name[1] = 'H'; + buf->Name[2] = '2'; + buf->Name[3] = 'C'; + return buf; +} + static int -add_durable_context(struct kvec *iov, unsigned int *num_iovec, +add_durable_v2_context(struct kvec *iov, unsigned int *num_iovec, struct cifs_open_parms *oparms) { struct smb2_create_req *req = iov[0].iov_base; unsigned int num = *num_iovec; + iov[num].iov_base = create_durable_v2_buf(oparms->fid); + if (iov[num].iov_base == NULL) + return -ENOMEM; + iov[num].iov_len = sizeof(struct create_durable_v2); + if (!req->CreateContextsOffset) + req->CreateContextsOffset = + cpu_to_le32(sizeof(struct smb2_create_req) - 4 + + iov[1].iov_len); + le32_add_cpu(&req->CreateContextsLength, sizeof(struct create_durable_v2)); + inc_rfc1001_len(&req->hdr, sizeof(struct create_durable_v2)); + *num_iovec = num + 1; + return 0; +} + +static int +add_durable_reconnect_v2_context(struct kvec *iov, unsigned int *num_iovec, + struct cifs_open_parms *oparms) +{ + struct smb2_create_req *req = iov[0].iov_base; + unsigned int num = *num_iovec; + + /* indicate that we don't need to relock the file */ + oparms->reconnect = false; + + iov[num].iov_base = create_reconnect_durable_v2_buf(oparms->fid); + if (iov[num].iov_base == NULL) + return -ENOMEM; + iov[num].iov_len = sizeof(struct create_durable_handle_reconnect_v2); + if (!req->CreateContextsOffset) + req->CreateContextsOffset = + cpu_to_le32(sizeof(struct smb2_create_req) - 4 + + iov[1].iov_len); + le32_add_cpu(&req->CreateContextsLength, + sizeof(struct create_durable_handle_reconnect_v2)); + inc_rfc1001_len(&req->hdr, + sizeof(struct create_durable_handle_reconnect_v2)); + *num_iovec = num + 1; + return 0; +} + +static int +add_durable_context(struct kvec *iov, unsigned int *num_iovec, + struct cifs_open_parms *oparms, bool use_persistent) +{ + struct smb2_create_req *req = iov[0].iov_base; + unsigned int num = *num_iovec; + + if (use_persistent) { + if (oparms->reconnect) + return add_durable_reconnect_v2_context(iov, num_iovec, + oparms); + else + return add_durable_v2_context(iov, num_iovec, oparms); + } + if (oparms->reconnect) { iov[num].iov_base = create_reconnect_durable_buf(oparms->fid); /* indicate that we don't need to relock the file */ @@ -1275,7 +1392,9 @@ SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path, ccontext->Next = cpu_to_le32(server->vals->create_lease_size); } - rc = add_durable_context(iov, &num_iovecs, oparms); + + rc = add_durable_context(iov, &num_iovecs, oparms, + tcon->use_persistent); if (rc) { cifs_small_buf_release(req); kfree(copy_path); -- cgit