nfs4proc.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,052 行 · 第 1/2 页

/*
 *  fs/nfsd/nfs4proc.c
 *
 *  Server-side procedures for NFSv4.
 *
 *  Copyright (c) 2002 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Kendrick Smith <[e-mail]>
 *  Andy Adamson   <[e-mail]>
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Note: some routines in this file are just trivial wrappers
 * (e.g. nfsd4_lookup()) defined solely for the sake of consistent
 * naming.  Since all such routines have been declared "inline",
 * there shouldn't be any associated overhead.  At some point in
 * the future, I might inline these "by hand" to clean up a
 * little.
 */

#include <linux/param.h>
#include <linux/major.h>
#include <linux/slab.h>

#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>
#include <linux/nfsd/cache.h>
#include <linux/nfs4.h>
#include <linux/nfsd/state.h>
#include <linux/nfsd/xdr4.h>
#include <linux/nfs4_acl.h>

#define NFSDDBG_FACILITY		NFSDDBG_PROC

static inline void
fh_dup2(struct svc_fh *dst, struct svc_fh *src)
{
	fh_put(dst);
	dget(src->fh_dentry);
	if (src->fh_export)
		cache_get(&src->fh_export->h);
	*dst = *src;
}

static int
do_open_permission(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	int accmode, status;

	if (open->op_truncate &&
		!(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
		return nfserr_inval;

	accmode = MAY_NOP;
	if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
		accmode = MAY_READ;
	if (open->op_share_deny & NFS4_SHARE_ACCESS_WRITE)
		accmode |= (MAY_WRITE | MAY_TRUNC);
	accmode |= MAY_OWNER_OVERRIDE;

	status = fh_verify(rqstp, current_fh, S_IFREG, accmode);

	return status;
}

static int
do_open_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	struct svc_fh resfh;
	int status;

	fh_init(&resfh, NFS4_FHSIZE);
	open->op_truncate = 0;

	if (open->op_create) {
		/*
		 * Note: create modes (UNCHECKED,GUARDED...) are the same
		 * in NFSv4 as in v3.
		 */
		status = nfsd_create_v3(rqstp, current_fh, open->op_fname.data,
					open->op_fname.len, &open->op_iattr,
					&resfh, open->op_createmode,
					(u32 *)open->op_verf.data, &open->op_truncate);
	}
	else {
		status = nfsd_lookup(rqstp, current_fh,
				     open->op_fname.data, open->op_fname.len, &resfh);
		fh_unlock(current_fh);
	}

	if (!status) {
		set_change_info(&open->op_cinfo, current_fh);

		/* set reply cache */
		fh_dup2(current_fh, &resfh);
		/* XXXJBF: keep a saved svc_fh struct instead?? */
		open->op_stateowner->so_replay.rp_openfh_len =
			resfh.fh_handle.fh_size;
		memcpy(open->op_stateowner->so_replay.rp_openfh,
				&resfh.fh_handle.fh_base,
				resfh.fh_handle.fh_size);

		status = do_open_permission(rqstp, current_fh, open);
	}

	fh_put(&resfh);
	return status;
}

static int
do_open_fhandle(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	int status;

	/* Only reclaims from previously confirmed clients are valid */
	if ((status = nfs4_check_open_reclaim(&open->op_clientid)))
		return status;

	/* We don't know the target directory, and therefore can not
	* set the change info
	*/

	memset(&open->op_cinfo, 0, sizeof(struct nfsd4_change_info));

	/* set replay cache */
	open->op_stateowner->so_replay.rp_openfh_len = current_fh->fh_handle.fh_size;
	memcpy(open->op_stateowner->so_replay.rp_openfh,
		&current_fh->fh_handle.fh_base,
		current_fh->fh_handle.fh_size);

	open->op_truncate = (open->op_iattr.ia_valid & ATTR_SIZE) &&
	!open->op_iattr.ia_size;

	status = do_open_permission(rqstp, current_fh, open);

	return status;
}


/*
 * nfs4_unlock_state() called in encode
 */
static inline int
nfsd4_open(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
{
	int status;
	dprintk("NFSD: nfsd4_open filename %.*s op_stateowner %p\n",
		(int)open->op_fname.len, open->op_fname.data,
		open->op_stateowner);

	if (nfs4_in_grace() && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS)
		return nfserr_grace;

	if (!nfs4_in_grace() && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)
		return nfserr_no_grace;

	/* This check required by spec. */
	if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL)
		return nfserr_inval;

	open->op_stateowner = NULL;
	nfs4_lock_state();

	/* check seqid for replay. set nfs4_owner */
	status = nfsd4_process_open1(open);
	if (status == NFSERR_REPLAY_ME) {
		struct nfs4_replay *rp = &open->op_stateowner->so_replay;
		fh_put(current_fh);
		current_fh->fh_handle.fh_size = rp->rp_openfh_len;
		memcpy(&current_fh->fh_handle.fh_base, rp->rp_openfh,
				rp->rp_openfh_len);
		status = fh_verify(rqstp, current_fh, 0, MAY_NOP);
		if (status)
			dprintk("nfsd4_open: replay failed"
				" restoring previous filehandle\n");
		else
			status = NFSERR_REPLAY_ME;
	}
	if (status)
		return status;
	if (open->op_claim_type == NFS4_OPEN_CLAIM_NULL) {
	/*
	 * This block of code will (1) set CURRENT_FH to the file being opened,
	 * creating it if necessary, (2) set open->op_cinfo, 
	 * (3) set open->op_truncate if the file is to be truncated 
	 * after opening, (4) do permission checking.
	 */
		status = do_open_lookup(rqstp, current_fh, open);
		if (status)
			return status;
	} else if (open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS) {
	/*
	* The CURRENT_FH is already set to the file being opened. This
	* block of code will (1) set open->op_cinfo, (2) set
	* open->op_truncate if the file is to be truncated after opening,
	* (3) do permission checking.
	*/
		status = do_open_fhandle(rqstp, current_fh, open);
		if (status)
			return status;
	} else {
		printk("NFSD: unsupported OPEN claim type\n");
		return nfserr_inval;
	}
	/*
	 * nfsd4_process_open2() does the actual opening of the file.  If
	 * successful, it (1) truncates the file if open->op_truncate was
	 * set, (2) sets open->op_stateid, (3) sets open->op_delegation.
	 */
	status = nfsd4_process_open2(rqstp, current_fh, open);
	if (status)
		return status;
	return 0;
}

/*
 * filehandle-manipulating ops.
 */
static inline int
nfsd4_getfh(struct svc_fh *current_fh, struct svc_fh **getfh)
{
	if (!current_fh->fh_dentry)
		return nfserr_nofilehandle;

	*getfh = current_fh;
	return nfs_ok;
}

static inline int
nfsd4_putfh(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_putfh *putfh)
{
	fh_put(current_fh);
	current_fh->fh_handle.fh_size = putfh->pf_fhlen;
	memcpy(&current_fh->fh_handle.fh_base, putfh->pf_fhval, putfh->pf_fhlen);
	return fh_verify(rqstp, current_fh, 0, MAY_NOP);
}

static inline int
nfsd4_putrootfh(struct svc_rqst *rqstp, struct svc_fh *current_fh)
{
	int status;

	fh_put(current_fh);
	status = exp_pseudoroot(rqstp->rq_client, current_fh,
			      &rqstp->rq_chandle);
	if (!status)
		status = nfsd_setuser(rqstp, current_fh->fh_export);
	return status;
}

static inline int
nfsd4_restorefh(struct svc_fh *current_fh, struct svc_fh *save_fh)
{
	if (!save_fh->fh_dentry)
		return nfserr_restorefh;

	fh_dup2(current_fh, save_fh);
	return nfs_ok;
}

static inline int
nfsd4_savefh(struct svc_fh *current_fh, struct svc_fh *save_fh)
{
	if (!current_fh->fh_dentry)
		return nfserr_nofilehandle;

	fh_dup2(save_fh, current_fh);
	return nfs_ok;
}

/*
 * misc nfsv4 ops
 */
static inline int
nfsd4_access(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_access *access)
{
	if (access->ac_req_access & ~NFS3_ACCESS_FULL)
		return nfserr_inval;

	access->ac_resp_access = access->ac_req_access;
	return nfsd_access(rqstp, current_fh, &access->ac_resp_access, &access->ac_supported);
}

static inline int
nfsd4_commit(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_commit *commit)
{
	int status;

	u32 *p = (u32 *)commit->co_verf.data;
	*p++ = nfssvc_boot.tv_sec;
	*p++ = nfssvc_boot.tv_usec;

	status = nfsd_commit(rqstp, current_fh, commit->co_offset, commit->co_count);
	if (status == nfserr_symlink)
		status = nfserr_inval;
	return status;
}

static int
nfsd4_create(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_create *create)
{
	struct svc_fh resfh;
	int status;
	dev_t rdev;

	fh_init(&resfh, NFS4_FHSIZE);

	status = fh_verify(rqstp, current_fh, S_IFDIR, MAY_CREATE);
	if (status == nfserr_symlink)
		status = nfserr_notdir;
	if (status)
		return status;

	switch (create->cr_type) {
	case NF4LNK:
		/* ugh! we have to null-terminate the linktext, or
		 * vfs_symlink() will choke.  it is always safe to
		 * null-terminate by brute force, since at worst we
		 * will overwrite the first byte of the create namelen
		 * in the XDR buffer, which has already been extracted
		 * during XDR decode.
		 */
		create->cr_linkname[create->cr_linklen] = 0;

		status = nfsd_symlink(rqstp, current_fh, create->cr_name,
				      create->cr_namelen, create->cr_linkname,
				      create->cr_linklen, &resfh, &create->cr_iattr);
		break;

	case NF4BLK:
		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
		if (MAJOR(rdev) != create->cr_specdata1 ||
		    MINOR(rdev) != create->cr_specdata2)
			return nfserr_inval;
		status = nfsd_create(rqstp, current_fh, create->cr_name,
				     create->cr_namelen, &create->cr_iattr,
				     S_IFBLK, rdev, &resfh);
		break;

	case NF4CHR:
		rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
		if (MAJOR(rdev) != create->cr_specdata1 ||
		    MINOR(rdev) != create->cr_specdata2)
			return nfserr_inval;
		status = nfsd_create(rqstp, current_fh, create->cr_name,
				     create->cr_namelen, &create->cr_iattr,
				     S_IFCHR, rdev, &resfh);
		break;

	case NF4SOCK:
		status = nfsd_create(rqstp, current_fh, create->cr_name,
				     create->cr_namelen, &create->cr_iattr,
				     S_IFSOCK, 0, &resfh);
		break;

	case NF4FIFO:
		status = nfsd_create(rqstp, current_fh, create->cr_name,
				     create->cr_namelen, &create->cr_iattr,
				     S_IFIFO, 0, &resfh);
		break;

	case NF4DIR:
		create->cr_iattr.ia_valid &= ~ATTR_SIZE;
		status = nfsd_create(rqstp, current_fh, create->cr_name,
				     create->cr_namelen, &create->cr_iattr,
				     S_IFDIR, 0, &resfh);
		break;

	default:
		status = nfserr_badtype;
	}

	if (!status) {
		fh_unlock(current_fh);
		set_change_info(&create->cr_cinfo, current_fh);
		fh_dup2(current_fh, &resfh);
	}

	fh_put(&resfh);
	return status;
}

static inline int
nfsd4_getattr(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_getattr *getattr)
{
	int status;

	status = fh_verify(rqstp, current_fh, 0, MAY_NOP);
	if (status)
		return status;

	if (getattr->ga_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
		return nfserr_inval;

	getattr->ga_bmval[0] &= NFSD_SUPPORTED_ATTRS_WORD0;
	getattr->ga_bmval[1] &= NFSD_SUPPORTED_ATTRS_WORD1;

	getattr->ga_fhp = current_fh;
	return nfs_ok;
}

static inline int
nfsd4_link(struct svc_rqst *rqstp, struct svc_fh *current_fh,
	   struct svc_fh *save_fh, struct nfsd4_link *link)
{
	int status = nfserr_nofilehandle;

	if (!save_fh->fh_dentry)
		return status;
	status = nfsd_link(rqstp, current_fh, link->li_name, link->li_namelen, save_fh);
	if (!status)
		set_change_info(&link->li_cinfo, current_fh);
	return status;
}

static int
nfsd4_lookupp(struct svc_rqst *rqstp, struct svc_fh *current_fh)
{
	struct svc_fh tmp_fh;
	int ret;

	fh_init(&tmp_fh, NFS4_FHSIZE);
	if((ret = exp_pseudoroot(rqstp->rq_client, &tmp_fh,
			      &rqstp->rq_chandle)) != 0)
		return ret;
	if (tmp_fh.fh_dentry == current_fh->fh_dentry) {
		fh_put(&tmp_fh);
		return nfserr_noent;
	}
	fh_put(&tmp_fh);
	return nfsd_lookup(rqstp, current_fh, "..", 2, current_fh);
}

static inline int
nfsd4_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_lookup *lookup)
{
	return nfsd_lookup(rqstp, current_fh, lookup->lo_name, lookup->lo_len, current_fh);
}

static inline int
access_bits_permit_read(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_READ, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap);
}

static inline int
access_bits_permit_write(unsigned long access_bmap)
{
	return test_bit(NFS4_SHARE_ACCESS_WRITE, &access_bmap) ||
		test_bit(NFS4_SHARE_ACCESS_BOTH, &access_bmap);
}

static inline int
nfsd4_read(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_read *read)
{
	struct nfs4_stateid *stp;
	int status;

	/* no need to check permission - this will be done in nfsd_read() */
	if (nfs4_in_grace())
		return nfserr_grace;

	if (read->rd_offset >= OFFSET_MAX)
		return nfserr_inval;

	nfs4_lock_state();
	status = nfs_ok;
	/* For stateid -1, we don't check share reservations.  */
	if (ONE_STATEID(&read->rd_stateid)) {
		dprintk("NFSD: nfsd4_read: -1 stateid...\n");
		goto out;
	}
	/*
	* For stateid 0, the client doesn't have to have the file open, but
	* we still check for share reservation conflicts. 
	*/
	if (ZERO_STATEID(&read->rd_stateid)) {
		dprintk("NFSD: nfsd4_read: zero stateid...\n");
		if ((status = nfs4_share_conflict(current_fh, NFS4_SHARE_DENY_READ))) {
			dprintk("NFSD: nfsd4_read: conflicting share reservation!\n");
			goto out;
		}
		status = nfs_ok;
		goto out;
	}
	/* check stateid */
	if ((status = nfs4_preprocess_stateid_op(current_fh, &read->rd_stateid, 
					CHECK_FH | RDWR_STATE, &stp))) {
		dprintk("NFSD: nfsd4_read: couldn't process stateid!\n");
		goto out;
	}
	status = nfserr_openmode;
	if (!access_bits_permit_read(stp->st_access_bmap)) {
		dprintk("NFSD: nfsd4_read: file not opened for read!\n");
		goto out;
	}
	status = nfs_ok;
out:
	nfs4_unlock_state();
	read->rd_rqstp = rqstp;
	read->rd_fhp = current_fh;