proc.c

Linux Kernel 2.6.9 for OMAP1710

/*
 *  linux/fs/nfs/proc.c
 *
 *  Copyright (C) 1992, 1993, 1994  Rick Sladkey
 *
 *  OS-independent nfs remote procedure call functions
 *
 *  Tuned by Alan Cox <[e-mail]> for >3K buffers
 *  so at last we can have decent(ish) throughput off a 
 *  Sun server.
 *
 *  Coding optimized and cleaned up by Florian La Roche.
 *  Note: Error returns are optimized for NFS_OK, which isn't translated via
 *  nfs_stat_to_errno(), but happens to be already the right return code.
 *
 *  Also, the code currently doesn't check the size of the packet, when
 *  it decodes the packet.
 *
 *  Feel free to fix it and mail me the diffs if it worries you.
 *
 *  Completely rewritten to support the new RPC call interface;
 *  rewrote and moved the entire XDR stuff to xdr.c
 *  --Olaf Kirch June 1996
 *
 *  The code below initializes all auto variables explicitly, otherwise
 *  it will fail to work as a module (gcc generates a memset call for an
 *  incomplete struct).
 */

#include <linux/types.h>
#include <linux/param.h>
#include <linux/slab.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/utsname.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs2.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_page.h>
#include <linux/lockd/bind.h>
#include <linux/smp_lock.h>

#define NFSDBG_FACILITY		NFSDBG_PROC

extern struct rpc_procinfo nfs_procedures[];

/*
 * Bare-bones access to getattr: this is for nfs_read_super.
 */
static int
nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
		  struct nfs_fsinfo *info)
{
	struct nfs_fattr *fattr = info->fattr;
	struct nfs2_fsstat fsinfo;
	int status;

	dprintk("%s: call getattr\n", __FUNCTION__);
	fattr->valid = 0;
	status = rpc_call(server->client_sys, NFSPROC_GETATTR, fhandle, fattr, 0);
	dprintk("%s: reply getattr %d\n", __FUNCTION__, status);
	if (status)
		return status;
	dprintk("%s: call statfs\n", __FUNCTION__);
	status = rpc_call(server->client_sys, NFSPROC_STATFS, fhandle, &fsinfo, 0);
	dprintk("%s: reply statfs %d\n", __FUNCTION__, status);
	if (status)
		return status;
	info->rtmax  = NFS_MAXDATA;
	info->rtpref = fsinfo.tsize;
	info->rtmult = fsinfo.bsize;
	info->wtmax  = NFS_MAXDATA;
	info->wtpref = fsinfo.tsize;
	info->wtmult = fsinfo.bsize;
	info->dtpref = fsinfo.tsize;
	info->maxfilesize = 0x7FFFFFFF;
	info->lease_time = 0;
	return 0;
}

/*
 * One function for each procedure in the NFS protocol.
 */
static int
nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
		struct nfs_fattr *fattr)
{
	int	status;

	dprintk("NFS call  getattr\n");
	fattr->valid = 0;
	status = rpc_call(server->client, NFSPROC_GETATTR,
				fhandle, fattr, 0);
	dprintk("NFS reply getattr\n");
	return status;
}

static int
nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
		 struct iattr *sattr)
{
	struct inode *inode = dentry->d_inode;
	struct nfs_sattrargs	arg = { 
		.fh	= NFS_FH(inode),
		.sattr	= sattr
	};
	int	status;

	dprintk("NFS call  setattr\n");
	fattr->valid = 0;
	status = rpc_call(NFS_CLIENT(inode), NFSPROC_SETATTR, &arg, fattr, 0);
	dprintk("NFS reply setattr\n");
	return status;
}

static int
nfs_proc_lookup(struct inode *dir, struct qstr *name,
		struct nfs_fh *fhandle, struct nfs_fattr *fattr)
{
	struct nfs_diropargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len
	};
	struct nfs_diropok	res = {
		.fh		= fhandle,
		.fattr		= fattr
	};
	int			status;

	dprintk("NFS call  lookup %s\n", name->name);
	fattr->valid = 0;
	status = rpc_call(NFS_CLIENT(dir), NFSPROC_LOOKUP, &arg, &res, 0);
	dprintk("NFS reply lookup: %d\n", status);
	return status;
}

static int nfs_proc_readlink(struct inode *inode, struct page *page,
		unsigned int pgbase, unsigned int pglen)
{
	struct nfs_readlinkargs	args = {
		.fh		= NFS_FH(inode),
		.pgbase		= pgbase,
		.pglen		= pglen,
		.pages		= &page
	};
	int			status;

	dprintk("NFS call  readlink\n");
	status = rpc_call(NFS_CLIENT(inode), NFSPROC_READLINK, &args, NULL, 0);
	dprintk("NFS reply readlink: %d\n", status);
	return status;
}

static int nfs_proc_read(struct nfs_read_data *rdata)
{
	int			flags = rdata->flags;
	struct inode *		inode = rdata->inode;
	struct nfs_fattr *	fattr = rdata->res.fattr;
	struct rpc_message	msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_READ],
		.rpc_argp	= &rdata->args,
		.rpc_resp	= &rdata->res,
		.rpc_cred	= rdata->cred,
	};
	int			status;

	dprintk("NFS call  read %d @ %Ld\n", rdata->args.count,
			(long long) rdata->args.offset);
	fattr->valid = 0;
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, flags);
	if (status >= 0) {
		nfs_refresh_inode(inode, fattr);
		/* Emulate the eof flag, which isn't normally needed in NFSv2
		 * as it is guaranteed to always return the file attributes
		 */
		if (rdata->args.offset + rdata->args.count >= fattr->size)
			rdata->res.eof = 1;
	}
	dprintk("NFS reply read: %d\n", status);
	return status;
}

static int nfs_proc_write(struct nfs_write_data *wdata)
{
	int			flags = wdata->flags;
	struct inode *		inode = wdata->inode;
	struct nfs_fattr *	fattr = wdata->res.fattr;
	struct rpc_message	msg = {
		.rpc_proc	= &nfs_procedures[NFSPROC_WRITE],
		.rpc_argp	= &wdata->args,
		.rpc_resp	= &wdata->res,
		.rpc_cred	= wdata->cred,
	};
	int			status;

	dprintk("NFS call  write %d @ %Ld\n", wdata->args.count,
			(long long) wdata->args.offset);
	fattr->valid = 0;
	status = rpc_call_sync(NFS_CLIENT(inode), &msg, flags);
	if (status >= 0) {
		nfs_refresh_inode(inode, fattr);
		wdata->res.count = wdata->args.count;
		wdata->verf.committed = NFS_FILE_SYNC;
	}
	dprintk("NFS reply write: %d\n", status);
	return status < 0? status : wdata->res.count;
}

static struct inode *
nfs_proc_create(struct inode *dir, struct qstr *name, struct iattr *sattr,
		int flags)
{
	struct nfs_fh		fhandle;
	struct nfs_fattr	fattr;
	struct nfs_createargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len,
		.sattr		= sattr
	};
	struct nfs_diropok	res = {
		.fh		= &fhandle,
		.fattr		= &fattr
	};
	int			status;

	fattr.valid = 0;
	dprintk("NFS call  create %s\n", name->name);
	status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);
	dprintk("NFS reply create: %d\n", status);
	if (status == 0) {
		struct inode *inode;
		inode = nfs_fhget(dir->i_sb, &fhandle, &fattr);
		if (inode)
			return inode;
		status = -ENOMEM;
	}
	return ERR_PTR(status);
}

/*
 * In NFSv2, mknod is grafted onto the create call.
 */
static int
nfs_proc_mknod(struct inode *dir, struct qstr *name, struct iattr *sattr,
	       dev_t rdev, struct nfs_fh *fhandle, struct nfs_fattr *fattr)
{
	struct nfs_createargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len,
		.sattr		= sattr
	};
	struct nfs_diropok	res = {
		.fh		= fhandle,
		.fattr		= fattr
	};
	int			status, mode;

	dprintk("NFS call  mknod %s\n", name->name);

	mode = sattr->ia_mode;
	if (S_ISFIFO(mode)) {
		sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
		sattr->ia_valid &= ~ATTR_SIZE;
	} else if (S_ISCHR(mode) || S_ISBLK(mode)) {
		sattr->ia_valid |= ATTR_SIZE;
		sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
	}

	fattr->valid = 0;
	status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);

	if (status == -EINVAL && S_ISFIFO(mode)) {
		sattr->ia_mode = mode;
		fattr->valid = 0;
		status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);
	}
	dprintk("NFS reply mknod: %d\n", status);
	return status;
}
  
static int
nfs_proc_remove(struct inode *dir, struct qstr *name)
{
	struct nfs_diropargs	arg = {
		.fh		= NFS_FH(dir),
		.name		= name->name,
		.len		= name->len
	};
	struct rpc_message	msg = { 
		.rpc_proc	= &nfs_procedures[NFSPROC_REMOVE],
		.rpc_argp	= &arg,
		.rpc_resp	= NULL,
		.rpc_cred	= NULL
	};
	int			status;

	dprintk("NFS call  remove %s\n", name->name);
	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);

	dprintk("NFS reply remove: %d\n", status);
	return status;
}

static int
nfs_proc_unlink_setup(struct rpc_message *msg, struct dentry *dir, struct qstr *name)
{
	struct nfs_diropargs	*arg;

	arg = (struct nfs_diropargs *)kmalloc(sizeof(*arg), GFP_KERNEL);
	if (!arg)
		return -ENOMEM;
	arg->fh = NFS_FH(dir->d_inode);
	arg->name = name->name;
	arg->len = name->len;
	msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
	msg->rpc_argp = arg;
	return 0;
}