// SPDX-License-Identifier: GPL-2.0
/*
 * Process version 2 NFS requests.
 *
 * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/namei.h>

#include "cache.h"
#include "xdr.h"
#include "vfs.h"

#define NFSDDBG_FACILITY                NFSDDBG_PROC

static __be32
nfsd_proc_null(struct svc_rqst *rqstp)
{
        return rpc_success;
}

/*
 * Get a file's attributes
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_getattr(struct svc_rqst *rqstp)
{
        struct nfsd_fhandle *argp = rqstp->rq_argp;
        struct nfsd_attrstat *resp = rqstp->rq_resp;

        dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));

        fh_copy(&resp->fh, &argp->fh);
        resp->status = fh_verify(rqstp, &resp->fh, 0,
                                 NFSD_MAY_NOP | NFSD_MAY_BYPASS_GSS_ON_ROOT);
        if (resp->status != nfs_ok)
                goto out;
        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/*
 * Set a file's attributes
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_setattr(struct svc_rqst *rqstp)
{
        struct nfsd_sattrargs *argp = rqstp->rq_argp;
        struct nfsd_attrstat *resp = rqstp->rq_resp;
        struct iattr *iap = &argp->attrs;
        struct svc_fh *fhp;

        dprintk("nfsd: SETATTR  %s, valid=%x, size=%ld\n",
                SVCFH_fmt(&argp->fh),
                argp->attrs.ia_valid, (long) argp->attrs.ia_size);

        fhp = fh_copy(&resp->fh, &argp->fh);

        /*
         * NFSv2 does not differentiate between "set-[ac]time-to-now"
         * which only requires access, and "set-[ac]time-to-X" which
         * requires ownership.
         * So if it looks like it might be "set both to the same time which
         * is close to now", and if setattr_prepare fails, then we
         * convert to "set to now" instead of "set to explicit time"
         *
         * We only call setattr_prepare as the last test as technically
         * it is not an interface that we should be using.
         */
#define BOTH_TIME_SET (ATTR_ATIME_SET | ATTR_MTIME_SET)
#define MAX_TOUCH_TIME_ERROR (30*60)
        if ((iap->ia_valid & BOTH_TIME_SET) == BOTH_TIME_SET &&
            iap->ia_mtime.tv_sec == iap->ia_atime.tv_sec) {
                /*
                 * Looks probable.
                 *
                 * Now just make sure time is in the right ballpark.
                 * Solaris, at least, doesn't seem to care what the time
                 * request is.  We require it be within 30 minutes of now.
                 */
                time64_t delta = iap->ia_atime.tv_sec - ktime_get_real_seconds();

                resp->status = fh_verify(rqstp, fhp, 0, NFSD_MAY_NOP);
                if (resp->status != nfs_ok)
                        goto out;

                if (delta < 0)
                        delta = -delta;
                if (delta < MAX_TOUCH_TIME_ERROR &&
                    setattr_prepare(&init_user_ns, fhp->fh_dentry, iap) != 0) {
                        /*
                         * Turn off ATTR_[AM]TIME_SET but leave ATTR_[AM]TIME.
                         * This will cause notify_change to set these times
                         * to "now"
                         */
                        iap->ia_valid &= ~BOTH_TIME_SET;
                }
        }

        resp->status = nfsd_setattr(rqstp, fhp, iap, 0, (time64_t)0);
        if (resp->status != nfs_ok)
                goto out;

        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/* Obsolete, replaced by MNTPROC_MNT. */
static __be32
nfsd_proc_root(struct svc_rqst *rqstp)
{
        return rpc_success;
}

/*
 * Look up a path name component
 * Note: the dentry in the resp->fh may be negative if the file
 * doesn't exist yet.
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_lookup(struct svc_rqst *rqstp)
{
        struct nfsd_diropargs *argp = rqstp->rq_argp;
        struct nfsd_diropres *resp = rqstp->rq_resp;

        dprintk("nfsd: LOOKUP   %s %.*s\n",
                SVCFH_fmt(&argp->fh), argp->len, argp->name);

        fh_init(&resp->fh, NFS_FHSIZE);
        resp->status = nfsd_lookup(rqstp, &argp->fh, argp->name, argp->len,
                                   &resp->fh);
        fh_put(&argp->fh);
        if (resp->status != nfs_ok)
                goto out;

        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/*
 * Read a symlink.
 */
static __be32
nfsd_proc_readlink(struct svc_rqst *rqstp)
{
        struct nfsd_fhandle *argp = rqstp->rq_argp;
        struct nfsd_readlinkres *resp = rqstp->rq_resp;

        dprintk("nfsd: READLINK %s\n", SVCFH_fmt(&argp->fh));

        /* Read the symlink. */
        resp->len = NFS_MAXPATHLEN;
        resp->page = *(rqstp->rq_next_page++);
        resp->status = nfsd_readlink(rqstp, &argp->fh,
                                     page_address(resp->page), &resp->len);

        fh_put(&argp->fh);
        return rpc_success;
}

/*
 * Read a portion of a file.
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_read(struct svc_rqst *rqstp)
{
        struct nfsd_readargs *argp = rqstp->rq_argp;
        struct nfsd_readres *resp = rqstp->rq_resp;
        unsigned int len;
        u32 eof;
        int v;

        dprintk("nfsd: READ    %s %d bytes at %d\n",
                SVCFH_fmt(&argp->fh),
                argp->count, argp->offset);

        argp->count = min_t(u32, argp->count, NFSSVC_MAXBLKSIZE_V2);

        v = 0;
        len = argp->count;
        resp->pages = rqstp->rq_next_page;
        while (len > 0) {
                struct page *page = *(rqstp->rq_next_page++);

                rqstp->rq_vec[v].iov_base = page_address(page);
                rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
                len -= rqstp->rq_vec[v].iov_len;
                v++;
        }

        /* Obtain buffer pointer for payload. 19 is 1 word for
         * status, 17 words for fattr, and 1 word for the byte count.
         */
        svc_reserve_auth(rqstp, (19<<2) + argp->count + 4);

        resp->count = argp->count;
        fh_copy(&resp->fh, &argp->fh);
        resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
                                 rqstp->rq_vec, v, &resp->count, &eof);
        if (resp->status == nfs_ok)
                resp->status = fh_getattr(&resp->fh, &resp->stat);
        else if (resp->status == nfserr_jukebox)
                return rpc_drop_reply;
        return rpc_success;
}

/* Reserved */
static __be32
nfsd_proc_writecache(struct svc_rqst *rqstp)
{
        return rpc_success;
}

/*
 * Write data to a file
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_write(struct svc_rqst *rqstp)
{
        struct nfsd_writeargs *argp = rqstp->rq_argp;
        struct nfsd_attrstat *resp = rqstp->rq_resp;
        unsigned long cnt = argp->len;
        unsigned int nvecs;

        dprintk("nfsd: WRITE    %s %d bytes at %d\n",
                SVCFH_fmt(&argp->fh),
                argp->len, argp->offset);

        nvecs = svc_fill_write_vector(rqstp, rqstp->rq_arg.pages,
                                      &argp->first, cnt);
        if (!nvecs) {
                resp->status = nfserr_io;
                goto out;
        }

        resp->status = nfsd_write(rqstp, fh_copy(&resp->fh, &argp->fh),
                                  argp->offset, rqstp->rq_vec, nvecs,
                                  &cnt, NFS_DATA_SYNC, NULL);
        if (resp->status == nfs_ok)
                resp->status = fh_getattr(&resp->fh, &resp->stat);
        else if (resp->status == nfserr_jukebox)
                return rpc_drop_reply;
out:
        return rpc_success;
}

/*
 * CREATE processing is complicated. The keyword here is `overloaded.'
 * The parent directory is kept locked between the check for existence
 * and the actual create() call in compliance with VFS protocols.
 * N.B. After this call _both_ argp->fh and resp->fh need an fh_put
 */
static __be32
nfsd_proc_create(struct svc_rqst *rqstp)
{
        struct nfsd_createargs *argp = rqstp->rq_argp;
        struct nfsd_diropres *resp = rqstp->rq_resp;
        svc_fh          *dirfhp = &argp->fh;
        svc_fh          *newfhp = &resp->fh;
        struct iattr    *attr = &argp->attrs;
        struct inode    *inode;
        struct dentry   *dchild;
        int             type, mode;
        int             hosterr;
        dev_t           rdev = 0, wanted = new_decode_dev(attr->ia_size);

        dprintk("nfsd: CREATE   %s %.*s\n",
                SVCFH_fmt(dirfhp), argp->len, argp->name);

        /* First verify the parent file handle */
        resp->status = fh_verify(rqstp, dirfhp, S_IFDIR, NFSD_MAY_EXEC);
        if (resp->status != nfs_ok)
                goto done; /* must fh_put dirfhp even on error */

        /* Check for NFSD_MAY_WRITE in nfsd_create if necessary */

        resp->status = nfserr_exist;
        if (isdotent(argp->name, argp->len))
                goto done;
        hosterr = fh_want_write(dirfhp);
        if (hosterr) {
                resp->status = nfserrno(hosterr);
                goto done;
        }

        fh_lock_nested(dirfhp, I_MUTEX_PARENT);
        dchild = lookup_one_len(argp->name, dirfhp->fh_dentry, argp->len);
        if (IS_ERR(dchild)) {
                resp->status = nfserrno(PTR_ERR(dchild));
                goto out_unlock;
        }
        fh_init(newfhp, NFS_FHSIZE);
        resp->status = fh_compose(newfhp, dirfhp->fh_export, dchild, dirfhp);
        if (!resp->status && d_really_is_negative(dchild))
                resp->status = nfserr_noent;
        dput(dchild);
        if (resp->status) {
                if (resp->status != nfserr_noent)
                        goto out_unlock;
                /*
                 * If the new file handle wasn't verified, we can't tell
                 * whether the file exists or not. Time to bail ...
                 */
                resp->status = nfserr_acces;
                if (!newfhp->fh_dentry) {
                        printk(KERN_WARNING 
                                "nfsd_proc_create: file handle not verified\n");
                        goto out_unlock;
                }
        }

        inode = d_inode(newfhp->fh_dentry);

        /* Unfudge the mode bits */
        if (attr->ia_valid & ATTR_MODE) {
                type = attr->ia_mode & S_IFMT;
                mode = attr->ia_mode & ~S_IFMT;
                if (!type) {
                        /* no type, so if target exists, assume same as that,
                         * else assume a file */
                        if (inode) {
                                type = inode->i_mode & S_IFMT;
                                switch(type) {
                                case S_IFCHR:
                                case S_IFBLK:
                                        /* reserve rdev for later checking */
                                        rdev = inode->i_rdev;
                                        attr->ia_valid |= ATTR_SIZE;

                                        fallthrough;
                                case S_IFIFO:
                                        /* this is probably a permission check..
                                         * at least IRIX implements perm checking on
                                         *   echo thing > device-special-file-or-pipe
                                         * by doing a CREATE with type==0
                                         */
                                        resp->status = nfsd_permission(rqstp,
                                                                 newfhp->fh_export,
                                                                 newfhp->fh_dentry,
                                                                 NFSD_MAY_WRITE|NFSD_MAY_LOCAL_ACCESS);
                                        if (resp->status && resp->status != nfserr_rofs)
                                                goto out_unlock;
                                }
                        } else
                                type = S_IFREG;
                }
        } else if (inode) {
                type = inode->i_mode & S_IFMT;
                mode = inode->i_mode & ~S_IFMT;
        } else {
                type = S_IFREG;
                mode = 0;       /* ??? */
        }

        attr->ia_valid |= ATTR_MODE;
        attr->ia_mode = mode;

        /* Special treatment for non-regular files according to the
         * gospel of sun micro
         */
        if (type != S_IFREG) {
                if (type != S_IFBLK && type != S_IFCHR) {
                        rdev = 0;
                } else if (type == S_IFCHR && !(attr->ia_valid & ATTR_SIZE)) {
                        /* If you think you've seen the worst, grok this. */
                        type = S_IFIFO;
                } else {
                        /* Okay, char or block special */
                        if (!rdev)
                                rdev = wanted;
                }

                /* we've used the SIZE information, so discard it */
                attr->ia_valid &= ~ATTR_SIZE;

                /* Make sure the type and device matches */
                resp->status = nfserr_exist;
                if (inode && inode_wrong_type(inode, type))
                        goto out_unlock;
        }

        resp->status = nfs_ok;
        if (!inode) {
                /* File doesn't exist. Create it and set attrs */
                resp->status = nfsd_create_locked(rqstp, dirfhp, argp->name,
                                                  argp->len, attr, type, rdev,
                                                  newfhp);
        } else if (type == S_IFREG) {
                dprintk("nfsd:   existing %s, valid=%x, size=%ld\n",
                        argp->name, attr->ia_valid, (long) attr->ia_size);
                /* File already exists. We ignore all attributes except
                 * size, so that creat() behaves exactly like
                 * open(..., O_CREAT|O_TRUNC|O_WRONLY).
                 */
                attr->ia_valid &= ATTR_SIZE;
                if (attr->ia_valid)
                        resp->status = nfsd_setattr(rqstp, newfhp, attr, 0,
                                                    (time64_t)0);
        }

out_unlock:
        /* We don't really need to unlock, as fh_put does it. */
        fh_unlock(dirfhp);
        fh_drop_write(dirfhp);
done:
        fh_put(dirfhp);
        if (resp->status != nfs_ok)
                goto out;
        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

static __be32
nfsd_proc_remove(struct svc_rqst *rqstp)
{
        struct nfsd_diropargs *argp = rqstp->rq_argp;
        struct nfsd_stat *resp = rqstp->rq_resp;

        dprintk("nfsd: REMOVE   %s %.*s\n", SVCFH_fmt(&argp->fh),
                argp->len, argp->name);

        /* Unlink. -SIFDIR means file must not be a directory */
        resp->status = nfsd_unlink(rqstp, &argp->fh, -S_IFDIR,
                                   argp->name, argp->len);
        fh_put(&argp->fh);
        return rpc_success;
}

static __be32
nfsd_proc_rename(struct svc_rqst *rqstp)
{
        struct nfsd_renameargs *argp = rqstp->rq_argp;
        struct nfsd_stat *resp = rqstp->rq_resp;

        dprintk("nfsd: RENAME   %s %.*s -> \n",
                SVCFH_fmt(&argp->ffh), argp->flen, argp->fname);
        dprintk("nfsd:        ->  %s %.*s\n",
                SVCFH_fmt(&argp->tfh), argp->tlen, argp->tname);

        resp->status = nfsd_rename(rqstp, &argp->ffh, argp->fname, argp->flen,
                                   &argp->tfh, argp->tname, argp->tlen);
        fh_put(&argp->ffh);
        fh_put(&argp->tfh);
        return rpc_success;
}

static __be32
nfsd_proc_link(struct svc_rqst *rqstp)
{
        struct nfsd_linkargs *argp = rqstp->rq_argp;
        struct nfsd_stat *resp = rqstp->rq_resp;

        dprintk("nfsd: LINK     %s ->\n",
                SVCFH_fmt(&argp->ffh));
        dprintk("nfsd:    %s %.*s\n",
                SVCFH_fmt(&argp->tfh),
                argp->tlen,
                argp->tname);

        resp->status = nfsd_link(rqstp, &argp->tfh, argp->tname, argp->tlen,
                                 &argp->ffh);
        fh_put(&argp->ffh);
        fh_put(&argp->tfh);
        return rpc_success;
}

static __be32
nfsd_proc_symlink(struct svc_rqst *rqstp)
{
        struct nfsd_symlinkargs *argp = rqstp->rq_argp;
        struct nfsd_stat *resp = rqstp->rq_resp;
        struct svc_fh   newfh;

        if (argp->tlen > NFS_MAXPATHLEN) {
                resp->status = nfserr_nametoolong;
                goto out;
        }

        argp->tname = svc_fill_symlink_pathname(rqstp, &argp->first,
                                                page_address(rqstp->rq_arg.pages[0]),
                                                argp->tlen);
        if (IS_ERR(argp->tname)) {
                resp->status = nfserrno(PTR_ERR(argp->tname));
                goto out;
        }

        dprintk("nfsd: SYMLINK  %s %.*s -> %.*s\n",
                SVCFH_fmt(&argp->ffh), argp->flen, argp->fname,
                argp->tlen, argp->tname);

        fh_init(&newfh, NFS_FHSIZE);
        resp->status = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen,
                                    argp->tname, &newfh);

        kfree(argp->tname);
        fh_put(&argp->ffh);
        fh_put(&newfh);
out:
        return rpc_success;
}

/*
 * Make directory. This operation is not idempotent.
 * N.B. After this call resp->fh needs an fh_put
 */
static __be32
nfsd_proc_mkdir(struct svc_rqst *rqstp)
{
        struct nfsd_createargs *argp = rqstp->rq_argp;
        struct nfsd_diropres *resp = rqstp->rq_resp;

        dprintk("nfsd: MKDIR    %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);

        if (resp->fh.fh_dentry) {
                printk(KERN_WARNING
                        "nfsd_proc_mkdir: response already verified??\n");
        }

        argp->attrs.ia_valid &= ~ATTR_SIZE;
        fh_init(&resp->fh, NFS_FHSIZE);
        resp->status = nfsd_create(rqstp, &argp->fh, argp->name, argp->len,
                                   &argp->attrs, S_IFDIR, 0, &resp->fh);
        fh_put(&argp->fh);
        if (resp->status != nfs_ok)
                goto out;

        resp->status = fh_getattr(&resp->fh, &resp->stat);
out:
        return rpc_success;
}

/*
 * Remove a directory
 */
static __be32
nfsd_proc_rmdir(struct svc_rqst *rqstp)
{
        struct nfsd_diropargs *argp = rqstp->rq_argp;
        struct nfsd_stat *resp = rqstp->rq_resp;

        dprintk("nfsd: RMDIR    %s %.*s\n", SVCFH_fmt(&argp->fh), argp->len, argp->name);

        resp->status = nfsd_unlink(rqstp, &argp->fh, S_IFDIR,
                                   argp->name, argp->len);
        fh_put(&argp->fh);
        return rpc_success;
}

static void nfsd_init_dirlist_pages(struct svc_rqst *rqstp,
                                    struct nfsd_readdirres *resp,
                                    int count)
{
        struct xdr_buf *buf = &resp->dirlist;
        struct xdr_stream *xdr = &resp->xdr;

        count = min_t(u32, count, PAGE_SIZE);

        memset(buf, 0, sizeof(*buf));

        /* Reserve room for the NULL ptr & eof flag (-2 words) */
        buf->buflen = count - sizeof(__be32) * 2;
        buf->pages = rqstp->rq_next_page;
        rqstp->rq_next_page++;

        /* This is xdr_init_encode(), but it assumes that
         * the head kvec has already been consumed. */
        xdr_set_scratch_buffer(xdr, NULL, 0);
        xdr->buf = buf;
        xdr->page_ptr = buf->pages;
        xdr->iov = NULL;
        xdr->p = page_address(*buf->pages);
        xdr->end = xdr->p + (PAGE_SIZE >> 2);
        xdr->rqst = NULL;
}

/*
 * Read a portion of a directory.
 */
static __be32
nfsd_proc_readdir(struct svc_rqst *rqstp)
{
        struct nfsd_readdirargs *argp = rqstp->rq_argp;
        struct nfsd_readdirres *resp = rqstp->rq_resp;
        loff_t          offset;

        dprintk("nfsd: READDIR  %s %d bytes at %d\n",
                SVCFH_fmt(&argp->fh),           
                argp->count, argp->cookie);

        nfsd_init_dirlist_pages(rqstp, resp, argp->count);

        resp->common.err = nfs_ok;
        resp->cookie_offset = 0;
        offset = argp->cookie;
        resp->status = nfsd_readdir(rqstp, &argp->fh, &offset,
                                    &resp->common, nfssvc_encode_entry);
        nfssvc_encode_nfscookie(resp, offset);

        fh_put(&argp->fh);
        return rpc_success;
}

/*
 * Get file system info
 */
static __be32
nfsd_proc_statfs(struct svc_rqst *rqstp)
{
        struct nfsd_fhandle *argp = rqstp->rq_argp;
        struct nfsd_statfsres *resp = rqstp->rq_resp;

        dprintk("nfsd: STATFS   %s\n", SVCFH_fmt(&argp->fh));

        resp->status = nfsd_statfs(rqstp, &argp->fh, &resp->stats,
                                   NFSD_MAY_BYPASS_GSS_ON_ROOT);
        fh_put(&argp->fh);
        return rpc_success;
}

/*
 * NFSv2 Server procedures.
 * Only the results of non-idempotent operations are cached.
 */

#define ST 1            /* status */
#define FH 8            /* filehandle */
#define AT 18           /* attributes */

static const struct svc_procedure nfsd_procedures2[18] = {
        [NFSPROC_NULL] = {
                .pc_func = nfsd_proc_null,
                .pc_decode = nfssvc_decode_voidarg,
                .pc_encode = nfssvc_encode_voidres,
                .pc_argsize = sizeof(struct nfsd_voidargs),
                .pc_ressize = sizeof(struct nfsd_voidres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = 0,
                .pc_name = "NULL",
        },
        [NFSPROC_GETATTR] = {
                .pc_func = nfsd_proc_getattr,
                .pc_decode = nfssvc_decode_fhandleargs,
                .pc_encode = nfssvc_encode_attrstatres,
                .pc_release = nfssvc_release_attrstat,
                .pc_argsize = sizeof(struct nfsd_fhandle),
                .pc_ressize = sizeof(struct nfsd_attrstat),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+AT,
                .pc_name = "GETATTR",
        },
        [NFSPROC_SETATTR] = {
                .pc_func = nfsd_proc_setattr,
                .pc_decode = nfssvc_decode_sattrargs,
                .pc_encode = nfssvc_encode_attrstatres,
                .pc_release = nfssvc_release_attrstat,
                .pc_argsize = sizeof(struct nfsd_sattrargs),
                .pc_ressize = sizeof(struct nfsd_attrstat),
                .pc_cachetype = RC_REPLBUFF,
                .pc_xdrressize = ST+AT,
                .pc_name = "SETATTR",
        },
        [NFSPROC_ROOT] = {
                .pc_func = nfsd_proc_root,
                .pc_decode = nfssvc_decode_voidarg,
                .pc_encode = nfssvc_encode_voidres,
                .pc_argsize = sizeof(struct nfsd_voidargs),
                .pc_ressize = sizeof(struct nfsd_voidres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = 0,
                .pc_name = "ROOT",
        },
        [NFSPROC_LOOKUP] = {
                .pc_func = nfsd_proc_lookup,
                .pc_decode = nfssvc_decode_diropargs,
                .pc_encode = nfssvc_encode_diropres,
                .pc_release = nfssvc_release_diropres,
                .pc_argsize = sizeof(struct nfsd_diropargs),
                .pc_ressize = sizeof(struct nfsd_diropres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+FH+AT,
                .pc_name = "LOOKUP",
        },
        [NFSPROC_READLINK] = {
                .pc_func = nfsd_proc_readlink,
                .pc_decode = nfssvc_decode_fhandleargs,
                .pc_encode = nfssvc_encode_readlinkres,
                .pc_argsize = sizeof(struct nfsd_fhandle),
                .pc_ressize = sizeof(struct nfsd_readlinkres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+1+NFS_MAXPATHLEN/4,
                .pc_name = "READLINK",
        },
        [NFSPROC_READ] = {
                .pc_func = nfsd_proc_read,
                .pc_decode = nfssvc_decode_readargs,
                .pc_encode = nfssvc_encode_readres,
                .pc_release = nfssvc_release_readres,
                .pc_argsize = sizeof(struct nfsd_readargs),
                .pc_ressize = sizeof(struct nfsd_readres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+AT+1+NFSSVC_MAXBLKSIZE_V2/4,
                .pc_name = "READ",
        },
        [NFSPROC_WRITECACHE] = {
                .pc_func = nfsd_proc_writecache,
                .pc_decode = nfssvc_decode_voidarg,
                .pc_encode = nfssvc_encode_voidres,
                .pc_argsize = sizeof(struct nfsd_voidargs),
                .pc_ressize = sizeof(struct nfsd_voidres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = 0,
                .pc_name = "WRITECACHE",
        },
        [NFSPROC_WRITE] = {
                .pc_func = nfsd_proc_write,
                .pc_decode = nfssvc_decode_writeargs,
                .pc_encode = nfssvc_encode_attrstatres,
                .pc_release = nfssvc_release_attrstat,
                .pc_argsize = sizeof(struct nfsd_writeargs),
                .pc_ressize = sizeof(struct nfsd_attrstat),
                .pc_cachetype = RC_REPLBUFF,
                .pc_xdrressize = ST+AT,
                .pc_name = "WRITE",
        },
        [NFSPROC_CREATE] = {
                .pc_func = nfsd_proc_create,
                .pc_decode = nfssvc_decode_createargs,
                .pc_encode = nfssvc_encode_diropres,
                .pc_release = nfssvc_release_diropres,
                .pc_argsize = sizeof(struct nfsd_createargs),
                .pc_ressize = sizeof(struct nfsd_diropres),
                .pc_cachetype = RC_REPLBUFF,
                .pc_xdrressize = ST+FH+AT,
                .pc_name = "CREATE",
        },
        [NFSPROC_REMOVE] = {
                .pc_func = nfsd_proc_remove,
                .pc_decode = nfssvc_decode_diropargs,
                .pc_encode = nfssvc_encode_statres,
                .pc_argsize = sizeof(struct nfsd_diropargs),
                .pc_ressize = sizeof(struct nfsd_stat),
                .pc_cachetype = RC_REPLSTAT,
                .pc_xdrressize = ST,
                .pc_name = "REMOVE",
        },
        [NFSPROC_RENAME] = {
                .pc_func = nfsd_proc_rename,
                .pc_decode = nfssvc_decode_renameargs,
                .pc_encode = nfssvc_encode_statres,
                .pc_argsize = sizeof(struct nfsd_renameargs),
                .pc_ressize = sizeof(struct nfsd_stat),
                .pc_cachetype = RC_REPLSTAT,
                .pc_xdrressize = ST,
                .pc_name = "RENAME",
        },
        [NFSPROC_LINK] = {
                .pc_func = nfsd_proc_link,
                .pc_decode = nfssvc_decode_linkargs,
                .pc_encode = nfssvc_encode_statres,
                .pc_argsize = sizeof(struct nfsd_linkargs),
                .pc_ressize = sizeof(struct nfsd_stat),
                .pc_cachetype = RC_REPLSTAT,
                .pc_xdrressize = ST,
                .pc_name = "LINK",
        },
        [NFSPROC_SYMLINK] = {
                .pc_func = nfsd_proc_symlink,
                .pc_decode = nfssvc_decode_symlinkargs,
                .pc_encode = nfssvc_encode_statres,
                .pc_argsize = sizeof(struct nfsd_symlinkargs),
                .pc_ressize = sizeof(struct nfsd_stat),
                .pc_cachetype = RC_REPLSTAT,
                .pc_xdrressize = ST,
                .pc_name = "SYMLINK",
        },
        [NFSPROC_MKDIR] = {
                .pc_func = nfsd_proc_mkdir,
                .pc_decode = nfssvc_decode_createargs,
                .pc_encode = nfssvc_encode_diropres,
                .pc_release = nfssvc_release_diropres,
                .pc_argsize = sizeof(struct nfsd_createargs),
                .pc_ressize = sizeof(struct nfsd_diropres),
                .pc_cachetype = RC_REPLBUFF,
                .pc_xdrressize = ST+FH+AT,
                .pc_name = "MKDIR",
        },
        [NFSPROC_RMDIR] = {
                .pc_func = nfsd_proc_rmdir,
                .pc_decode = nfssvc_decode_diropargs,
                .pc_encode = nfssvc_encode_statres,
                .pc_argsize = sizeof(struct nfsd_diropargs),
                .pc_ressize = sizeof(struct nfsd_stat),
                .pc_cachetype = RC_REPLSTAT,
                .pc_xdrressize = ST,
                .pc_name = "RMDIR",
        },
        [NFSPROC_READDIR] = {
                .pc_func = nfsd_proc_readdir,
                .pc_decode = nfssvc_decode_readdirargs,
                .pc_encode = nfssvc_encode_readdirres,
                .pc_argsize = sizeof(struct nfsd_readdirargs),
                .pc_ressize = sizeof(struct nfsd_readdirres),
                .pc_cachetype = RC_NOCACHE,
                .pc_name = "READDIR",
        },
        [NFSPROC_STATFS] = {
                .pc_func = nfsd_proc_statfs,
                .pc_decode = nfssvc_decode_fhandleargs,
                .pc_encode = nfssvc_encode_statfsres,
                .pc_argsize = sizeof(struct nfsd_fhandle),
                .pc_ressize = sizeof(struct nfsd_statfsres),
                .pc_cachetype = RC_NOCACHE,
                .pc_xdrressize = ST+5,
                .pc_name = "STATFS",
        },
};


static unsigned int nfsd_count2[ARRAY_SIZE(nfsd_procedures2)];
const struct svc_version nfsd_version2 = {
        .vs_vers        = 2,
        .vs_nproc       = 18,
        .vs_proc        = nfsd_procedures2,
        .vs_count       = nfsd_count2,
        .vs_dispatch    = nfsd_dispatch,
        .vs_xdrsize     = NFS2_SVC_XDRSIZE,
};

/*
 * Map errnos to NFS errnos.
 */
__be32
nfserrno (int errno)
{
        static struct {
                __be32  nfserr;
                int     syserr;
        } nfs_errtbl[] = {
                { nfs_ok, 0 },
                { nfserr_perm, -EPERM },
                { nfserr_noent, -ENOENT },
                { nfserr_io, -EIO },
                { nfserr_nxio, -ENXIO },
                { nfserr_fbig, -E2BIG },
                { nfserr_acces, -EACCES },
                { nfserr_exist, -EEXIST },
                { nfserr_xdev, -EXDEV },
                { nfserr_mlink, -EMLINK },
                { nfserr_nodev, -ENODEV },
                { nfserr_notdir, -ENOTDIR },
                { nfserr_isdir, -EISDIR },
                { nfserr_inval, -EINVAL },
                { nfserr_fbig, -EFBIG },
                { nfserr_nospc, -ENOSPC },
                { nfserr_rofs, -EROFS },
                { nfserr_mlink, -EMLINK },
                { nfserr_nametoolong, -ENAMETOOLONG },
                { nfserr_notempty, -ENOTEMPTY },
#ifdef EDQUOT
                { nfserr_dquot, -EDQUOT },
#endif
                { nfserr_stale, -ESTALE },
                { nfserr_jukebox, -ETIMEDOUT },
                { nfserr_jukebox, -ERESTARTSYS },
                { nfserr_jukebox, -EAGAIN },
                { nfserr_jukebox, -EWOULDBLOCK },
                { nfserr_jukebox, -ENOMEM },
                { nfserr_io, -ETXTBSY },
                { nfserr_notsupp, -EOPNOTSUPP },
                { nfserr_toosmall, -ETOOSMALL },
                { nfserr_serverfault, -ESERVERFAULT },
                { nfserr_serverfault, -ENFILE },
                { nfserr_io, -EUCLEAN },
                { nfserr_perm, -ENOKEY },
        };
        int     i;

        for (i = 0; i < ARRAY_SIZE(nfs_errtbl); i++) {
                if (nfs_errtbl[i].syserr == errno)
                        return nfs_errtbl[i].nfserr;
        }
        WARN_ONCE(1, "nfsd: non-standard errno: %d\n", errno);
        return nfserr_io;
}