kernel/include/linux/nfs_fs_sb.h, branch linux-3.6.y

NFS: Convert v4 into a module

2012-07-30T23:06:52Z

This patch exports symbols needed by the v4 module. In addition, I also switch over to using IS_ENABLED() to check if CONFIG_NFS_V4 or CONFIG_NFS_V4_MODULE are set. The module (nfs4.ko) will be created in the same directory as nfs.ko and will be automatically loaded the first time you try to mount over NFS v4. Signed-off-by: Bryan Schumaker Signed-off-by: Trond Myklebust

NFS: Add version registering framework

2012-07-30T23:04:17Z

This patch adds in the code to track multiple versions of the NFS protocol. I created default structures for v2, v3 and v4 so that each version can continue to work while I convert them into kernel modules. I also removed the const parameter from the rpc_version array so that I can change it at runtime. Signed-off-by: Bryan Schumaker Signed-off-by: Trond Myklebust

NFS: Treat NFS4ERR_CLID_INUSE as a fatal error

2012-07-16T19:12:16Z

For NFSv4 minor version 0, currently the cl_id_uniquifier allows the Linux client to generate a unique nfs_client_id4 string whenever a server replies with NFS4ERR_CLID_INUSE. This implementation seems to be based on a flawed reading of RFC 3530. NFS4ERR_CLID_INUSE actually means that the client has presented this nfs_client_id4 string with a different principal at some time in the past, and that lease is still in use on the server. For a Linux client this might be rather difficult to achieve: the authentication flavor is named right in the nfs_client_id4.id string. If we change flavors, we change strings automatically. So, practically speaking, NFS4ERR_CLID_INUSE means there is some other client using our string. There is not much that can be done to recover automatically. Let's make it a permanent error. Remove the recovery logic in nfs4_proc_setclientid(), and remove the cl_id_uniquifier field from the nfs_client data structure. And, remove the authentication flavor from the nfs_client_id4 string. Keeping the authentication flavor in the nfs_client_id4.id string means that we could have a separate lease for each authentication flavor used by mounts on the client. But we want just one lease for all the mounts on this client. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFSv4.1: Fix umount when filelayout DS is also the MDS

2012-06-18T12:45:16Z

Currently there is a 'chicken and egg' issue when the DS is also the mounted MDS. The nfs_match_client() reference from nfs4_set_ds_client bumps the cl_count, the nfs_client is not freed at umount, and nfs4_deviceid_purge_client is not called to dereference the MDS usage of a deviceid which holds a reference to the DS nfs_client. The result is the umount program returns, but the nfs_client is not freed, and the cl_session hearbeat continues. The MDS (and all other nfs mounts) lose their last nfs_client reference in nfs_free_server when the last nfs_server (fsid) is umounted. The file layout DS lose their last nfs_client reference in destroy_ds when the last deviceid referencing the data server is put and destroy_ds is called. This is triggered by a call to nfs4_deviceid_purge_client which removes references to a pNFS deviceid used by an MDS mount. The fix is to track how many pnfs enabled filesystems are mounted from this server, and then to purge the device id cache once that count reaches zero. Reported-by: Jorge Mora Reported-by: Andy Adamson Signed-off-by: Trond Myklebust

NFS: EXCHANGE_ID should save the server major and minor ID

2012-05-22T20:45:48Z

Save the server major and minor ID results from EXCHANGE_ID, as they are needed for detecting server trunking. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFS: Add nfs_client behavior flags

2012-05-22T20:45:47Z

"noresvport" and "discrtry" can be passed to nfs_create_rpc_client() by setting flags in the passed-in nfs_client. This change makes it easy to add new flags. Note that these settings are now "sticky" over the lifetime of a struct nfs_client, and may even be copied when an nfs_client is cloned. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFS: Always use the same SETCLIENTID boot verifier

2012-05-22T20:45:46Z

Currently our NFS client assigns a unique SETCLIENTID boot verifier for each server IP address it knows about. It's set to CURRENT_TIME when the struct nfs_client for that server IP is created. During the SETCLIENTID operation, our client also presents an nfs_client_id4 string to servers, as an identifier on which the server can hang all of this client's NFSv4 state. Our client's nfs_client_id4 string is unique for each server IP address. An NFSv4 server is obligated to wipe all NFSv4 state associated with an nfs_client_id4 string when the client presents the same nfs_client_id4 string along with a changed SETCLIENTID boot verifier. When our client unmounts the last of a server's shares, it destroys that server's struct nfs_client. The next time the client mounts that NFS server, it creates a fresh struct nfs_client with a fresh boot verifier. On seeing the fresh verifer, the server wipes any previous NFSv4 state associated with that nfs_client_id4. However, NFSv4.1 clients are supposed to present the same nfs_client_id4 string to all servers. And, to support Transparent State Migration, the same nfs_client_id4 string should be presented to all NFSv4.0 servers so they recognize that migrated state for this client belongs with state a server may already have for this client. (This is known as the Uniform Client String model). If the nfs_client_id4 string is the same but the boot verifier changes for each server IP address, SETCLIENTID and EXCHANGE_ID operations from such a client could unintentionally result in a server wiping a client's previously obtained lease. Thus, if our NFS client is going to use a fixed nfs_client_id4 string, either for NFSv4.0 or NFSv4.1 mounts, our NFS client should use a boot verifier that does not change depending on server IP address. Replace our current per-nfs_client boot verifier with a per-nfs_net boot verifier. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFS: Use proper naming conventions for the nfs_client.net field

2012-05-22T20:45:44Z

Clean up: When naming fields and data types, follow established conventions to facilitate accurate grep/cscope searches. Introduced by commit e50a7a1a "NFS: make NFS client allocated per network namespace context," Tue Jan 10, 2012. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFS: Use proper naming conventions for nfs_client.impl_id field

2012-05-22T20:45:43Z

Clean up: When naming fields and data types, follow established conventions to facilitate accurate grep/cscope searches. Additionally, for consistency, move the impl_id field into the NFSv4- specific part of the nfs_client, and free that memory in the logic that shuts down NFSv4 nfs_clients. Introduced by commit 7d2ed9ac "NFSv4: parse and display server implementation ids," Fri Feb 17, 2012. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust

NFS: Use proper naming conventions for NFSv4.1 server scope fields

2012-05-22T20:45:43Z

Clean up: When naming fields and data types, follow established conventions to facilitate accurate grep/cscope searches. Additionally, for consistency, move the scope field into the NFSv4- specific part of the nfs_client, and free that memory in the logic that shuts down NFSv4 nfs_clients. Introduced by commit 99fe60d0 "nfs41: exchange_id operation", April 1 2009. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust