/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Simple nfs ops - open, close, read, and lseek.
 */

#pragma ident   "%Z%%M% %I%     %E% SMI"

#include <rpc/types.h>
#include <rpc/auth.h>
#include <sys/t_lock.h>
#include "clnt.h"
#include <sys/fcntl.h>
#include <sys/vfs.h>
#include <errno.h>
#include <sys/promif.h>
#include <rpc/xdr.h>
#include "nfs_inet.h"
#include <sys/stat.h>
#include <sys/bootvfs.h>
#include <sys/bootdebug.h>
#include <sys/salib.h>
#include <sys/sacache.h>
#include <rpc/rpc.h>
#include "brpc.h"
#include <rpcsvc/nfs_prot.h>
#include "socket_inet.h"
#include "mac.h"
#include <sys/mode.h>

ushort_t vttoif_tab[] = {
        0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFIFO,
        S_IFDOOR, 0, S_IFSOCK, 0
};

static int file_desc = 1;
static struct nfs_files {
        struct nfs_file file;
        int     desc;
        struct nfs_files *next;
} nfs_files[1] = {
        {0, 0, 0},
};

#define dprintf if (boothowto & RB_DEBUG) printf

static int      boot_nfs_open(char *filename, int flags);
static int      boot_nfs_close(int fd);
static ssize_t  boot_nfs_read(int fd, caddr_t buf, size_t size);
static off_t    boot_nfs_lseek(int, off_t, int);
static int      boot_nfs_fstat(int fd, struct bootstat *stp);
static void     boot_nfs_closeall(int flag);
static int      boot_nfs_getdents(int fd, struct dirent *dep, unsigned size);

struct boot_fs_ops boot_nfs_ops = {
        "nfs",
        boot_nfs_mountroot,
        boot_nfs_unmountroot,
        boot_nfs_open,
        boot_nfs_close,
        boot_nfs_read,
        boot_nfs_lseek,
        boot_nfs_fstat,
        boot_nfs_closeall,
        boot_nfs_getdents
};

/*
 * bootops.c calls a closeall() function to close all open files. Since
 * we only permit one open file at a time (not counting the device), this
 * is simple to implement.
 */

/*ARGSUSED*/
static void
boot_nfs_closeall(int flag)
{
        struct nfs_files        *filep;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_closeall(%x)\n", flag);
#endif

        if (nfs_files->file.version == 0 &&
            nfs_files->desc == 0 &&
            nfs_files->next == NULL)
                return;

        /* delete any dynamically allocated entries */
        while ((filep = nfs_files->next) != NULL) {
                nfs_files->next = filep->next;
                bkmem_free((caddr_t)filep, sizeof (struct  nfs_files));
        }

        /* clear the first, static file */
        bzero((caddr_t)nfs_files, sizeof (struct nfs_files));

        /* Close device */
        release_cache(mac_get_dev());

        mac_fini();
}

/*
 * Get a file pointer given a file descriptor.  Return 0 on error
 */
static struct nfs_files *
get_filep(int fd)
{
        struct nfs_files *filep;

        for (filep = nfs_files; filep; filep = filep->next) {
                if (fd == filep->desc)
                        return (filep);
        }
        return (NULL);
}

/*
 * Unmount the root fs -- not supported for this fstype.
 */

int
boot_nfs_unmountroot(void)
{
        return (-1);
}

/*
 * open a file for reading. Note: writing is NOT supported.
 */

static int
boot_nfs_open(char *path, int flags)
{
        struct nfs_files *filep, *newfilep;
        int got_filep;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_open(%s, %x)\n", path, flags);
#endif

        /* file can only be opened readonly. */
        if (flags & ~O_RDONLY) {
                dprintf("boot_nfs_open: files can only be opened O_RDONLY.\n");
                return (-1);
        }

        if (path == NULL || *path == '\0') {
                dprintf("boot_nfs_open: NULL or EMPTY pathname argument.\n");
                return (-1);
        }

        /* Try and find a vacant file pointer */
        filep = nfs_files;
        got_filep = FALSE;
        do {
                if (filep->desc == 0) {
                        filep->desc = file_desc++;
                        got_filep = TRUE;
                        break;          /* We've got a file pointer */
                }
                /* Get next entry if not at end of list */
                if (filep->next)
                        filep = filep->next;
        } while (filep->next);

        /* If a a vacant file pointer cannot be found, make one */
        if (!got_filep) {
                if ((newfilep = (struct nfs_files *)
                    bkmem_zalloc(sizeof (struct nfs_files))) == 0) {
                        dprintf("open: Cannot allocate file pointer\n");
                        return (-1);
                }
                filep->next = newfilep;
                filep = newfilep;
                filep->desc = file_desc++;
        }

        if (lookup(path, &filep->file, FALSE) != 0) {
#ifdef NFS_OPS_DEBUG
                if ((boothowto & DBFLAGS) == DBFLAGS)
                        printf("boot_nfs_open(): Cannot open '%s'.\n", path);
#endif
                /* zero file pointer */
                bzero((caddr_t)filep, sizeof (struct nfs_file));
                filep->desc = 0;
                return (-1);
        }
        bzero(&filep->file.cookie, sizeof (filep->file.cookie));

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_open(): '%s' successful, fd = 0x%x\n",
                    path, filep->desc);
#endif
        return (filep->desc);
}

/*
 * close a previously opened file.
 */
static int
boot_nfs_close(int fd)
{
        struct nfs_files *filep;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_close(%d)\n", fd);
#endif
        if ((filep = get_filep(fd)) == 0)
                return (0);

        /*
         * zero file pointer
         */
        bzero((caddr_t)&filep->file, sizeof (struct nfs_file));

        /*
         * "close" the fd.
         */
        filep->desc = 0;

        return (0);
}

/*
 * read from a file.
 */
static ssize_t
boot_nfs_read(int fd, char *buf, size_t size)
{
        struct nfs_files        *filep;
        int                     count = 0;

        if (fd == 0) {
                dprintf("boot_nfs_read: Bad file number.\n");
                return (-1);
        }
        if (buf == NULL) {
                dprintf("boot_nfs_read: Bad address.\n");
                return (-1);
        }

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_read(%d, %x, 0x%x)\n", fd, buf, size);
#endif

        /* initialize for read */
        if ((filep = get_filep(fd)) == 0)
                return (-1);

        switch (filep->file.version) {
        case NFS_VERSION:
                count = nfsread(&filep->file, buf, size);
                break;
        case NFS_V3:
                count = nfs3read(&filep->file, buf, size);
                break;
        case NFS_V4:
                count = nfs4read(&filep->file, buf, size);
                break;
        default:
                printf("boot_nfs_read: NFS Version %d not supported\n",
                    filep->file.version);
                count = -1;
                break;
        }

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_read(): 0x%x bytes.\n", count);
#endif
        return (count);
}

/*
 * lseek - move read file pointer.
 */

static off_t
boot_nfs_lseek(int fd, off_t offset, int whence)
{
        struct nfs_files *filep;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_lseek(%d, 0x%x, %d)\n", fd, offset, whence);
#endif

        if (fd == 0) {
                dprintf("boot_nfs_lseek: Bad file number.\n");
                return (-1);
        }

        if ((filep = get_filep(fd)) == 0)
                return (-1);

        switch (whence) {

        case SEEK_SET:
                /*
                 * file ptr is set to offset from beginning of file
                 */
                filep->file.offset = offset;
                break;
        case SEEK_CUR:
                /*
                 * file ptr is set to offset from current position
                 */
                filep->file.offset += offset;
                break;
        case SEEK_END:
                /*
                 * file ptr is set to current size of file plus offset.
                 * But since we only support reading, this is illegal.
                 */
        default:
                /*
                 * invalid offset origin
                 */
                dprintf("boot_nfs_lseek: invalid whence value.\n");
                return (-1);
        }

#ifdef notyet
        return (filep->file.offset);
#else
        /*
         * BROKE - lseek should return the offset seeked to on a
         * successful seek, not zero - This must be fixed in the
         * kernel before It can be fixed here.
         */
        return (0);
#endif /* notyet */
}

/*
 * This version of fstat supports mode, size, inode #, and times only.
 * It can be enhanced if more is required,
 */

static int
boot_nfs_fstat(int fd, struct bootstat *stp)
{
        struct vattr va;
        struct nfs_files *filep;
        int status;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS) {
                printf("boot_nfs_fstat(%d, 0x%x)\n", fd, stp);
        }
#endif
        if (fd == 0) {
                dprintf("boot_nfs_fstat(): Bad file number 0.\n");
                return (-1);
        }

        if ((filep = get_filep(fd)) == 0)
                return (-1);

        bzero((char *)&va, sizeof (va));
        va.va_mask = AT_TYPE | AT_SIZE | AT_MODE | AT_NODEID |
            AT_ATIME | AT_CTIME | AT_MTIME;

        switch (filep->file.version) {
        case NFS_VERSION:
                status = nfsgetattr(&filep->file, &va);
                break;
        case NFS_V3:
                status = nfs3getattr(&filep->file, &va);
                break;
        case NFS_V4:
                status = nfs4getattr(&filep->file, &va);
                break;
        default:
                printf("boot_nfs_fstat: NFS Version %d not supported\n",
                    filep->file.version);
                status = -1;
                break;
        }

        if (status != 0)
                return (-1);

        if (va.va_size > (u_offset_t)MAXOFF_T) {
                dprintf("boot_nfs_fstat(): File too large.\n");
                return (-1);
        }
        stp->st_size = (off_t)va.va_size;
        stp->st_mode = VTTOIF(va.va_type) | va.va_mode;
        stp->st_atim.tv_sec = va.va_atime.tv_sec;
        stp->st_atim.tv_nsec = va.va_atime.tv_nsec;
        stp->st_ctim.tv_sec = va.va_ctime.tv_sec;
        stp->st_ctim.tv_nsec = va.va_ctime.tv_nsec;
        stp->st_mtim.tv_sec = va.va_mtime.tv_sec;
        stp->st_mtim.tv_nsec = va.va_mtime.tv_nsec;
        stp->st_ino = (ino_t)va.va_nodeid;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_fstat(): done.\n");
#endif
        return (0);
}

static int
boot_nfs_getdents(int fd, struct dirent *dep, unsigned size)
{
        struct nfs_files *filep;
        int status;

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS) {
                printf("boot_nfs_getdents(%d, 0x%x, 0x%x)\n", fd, dep, size);
        }
#endif

        if (fd == 0) {
                dprintf("boot_nfs_getdents(): Bad file number 0.\n");
                return (-1);
        }

        if ((filep = get_filep(fd)) == 0)
                return (-1);

        switch (filep->file.version) {
        case NFS_VERSION:
                status = nfsgetdents(&filep->file, dep, size);
                break;
        case NFS_V3:
                status = nfs3getdents(&filep->file, dep, size);
                break;
        default:
                printf("boot_nfs_getdents: NFS Version %d not supported\n",
                    filep->file.version);
                status = -1;
        }

#ifdef NFS_OPS_DEBUG
        if ((boothowto & DBFLAGS) == DBFLAGS)
                printf("boot_nfs_getdents(): done.\n");
#endif
        return (status);
}