From 1c6dcbe5ceff81c2cf8d929646af675cd59fe7c0 Mon Sep 17 00:00:00 2001 From: Anna Schumaker Date: Fri, 26 Sep 2014 13:58:48 -0400 Subject: NFS: Implement SEEK The SEEK operation is used when an application makes an lseek call with either the SEEK_HOLE or SEEK_DATA flags set. I fall back on nfs_file_llseek() if the server does not have SEEK support. Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust --- fs/nfs/nfs42proc.c | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 fs/nfs/nfs42proc.c (limited to 'fs/nfs/nfs42proc.c') diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c new file mode 100644 index 000000000000..0886f1db5917 --- /dev/null +++ b/fs/nfs/nfs42proc.c @@ -0,0 +1,69 @@ +/* + * Copyright (c) 2014 Anna Schumaker + */ +#include +#include +#include +#include +#include +#include +#include +#include "nfs4_fs.h" +#include "nfs42.h" + +static int nfs42_set_rw_stateid(nfs4_stateid *dst, struct file *file, + fmode_t fmode) +{ + struct nfs_open_context *open; + struct nfs_lock_context *lock; + int ret; + + open = get_nfs_open_context(nfs_file_open_context(file)); + lock = nfs_get_lock_context(open); + if (IS_ERR(lock)) { + put_nfs_open_context(open); + return PTR_ERR(lock); + } + + ret = nfs4_set_rw_stateid(dst, open, lock, fmode); + + nfs_put_lock_context(lock); + put_nfs_open_context(open); + return ret; +} + +loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence) +{ + struct inode *inode = file_inode(filep); + struct nfs42_seek_args args = { + .sa_fh = NFS_FH(inode), + .sa_offset = offset, + .sa_what = (whence == SEEK_HOLE) ? + NFS4_CONTENT_HOLE : NFS4_CONTENT_DATA, + }; + struct nfs42_seek_res res; + struct rpc_message msg = { + .rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_SEEK], + .rpc_argp = &args, + .rpc_resp = &res, + }; + struct nfs_server *server = NFS_SERVER(inode); + int status; + + if (!(server->caps & NFS_CAP_SEEK)) + return -ENOTSUPP; + + status = nfs42_set_rw_stateid(&args.sa_stateid, filep, FMODE_READ); + if (status) + return status; + + nfs_wb_all(inode); + status = nfs4_call_sync(server->client, server, &msg, + &args.seq_args, &res.seq_res, 0); + if (status == -ENOTSUPP) + server->caps &= ~NFS_CAP_SEEK; + if (status) + return status; + + return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes); +} -- cgit v1.2.3