/*
 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include "xfs.h"
#include "xfs_vnodeops.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"

/*
 * And this gunk is needed for xfs_mount.h"
 */
#include "xfs_log.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_dmapi.h"
#include "xfs_inum.h"
#include "xfs_ag.h"
#include "xfs_mount.h"


/*
 * Dedicated vnode inactive/reclaim sync semaphores.
 * Prime number of hash buckets since address is used as the key.
 */
#define NVSYNC                  37
#define vptosync(v)             (&vsync[((unsigned long)v) % NVSYNC])
static wait_queue_head_t vsync[NVSYNC];

void
vn_init(void)
{
        int i;

        for (i = 0; i < NVSYNC; i++)
                init_waitqueue_head(&vsync[i]);
}

void
vn_iowait(
        xfs_inode_t     *ip)
{
        wait_queue_head_t *wq = vptosync(ip);

        wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
}

void
vn_iowake(
        xfs_inode_t     *ip)
{
        if (atomic_dec_and_test(&ip->i_iocount))
                wake_up(vptosync(ip));
}

/*
 * Volume managers supporting multiple paths can send back ENODEV when the
 * final path disappears.  In this case continuing to fill the page cache
 * with dirty data which cannot be written out is evil, so prevent that.
 */
void
vn_ioerror(
        xfs_inode_t     *ip,
        int             error,
        char            *f,
        int             l)
{
        if (unlikely(error == -ENODEV))
                xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ, f, l);
}

bhv_vnode_t *
vn_initialize(
        struct inode    *inode)
{
        bhv_vnode_t     *vp = vn_from_inode(inode);

        XFS_STATS_INC(vn_active);
        XFS_STATS_INC(vn_alloc);

        ASSERT(VN_CACHED(vp) == 0);

        return vp;
}

/*
 * Revalidate the Linux inode from the vattr.
 * Note: i_size _not_ updated; we must hold the inode
 * semaphore when doing that - callers responsibility.
 */
void
vn_revalidate_core(
        bhv_vnode_t     *vp,
        bhv_vattr_t     *vap)
{
        struct inode    *inode = vn_to_inode(vp);

        inode->i_mode       = vap->va_mode;
        inode->i_nlink      = vap->va_nlink;
        inode->i_uid        = vap->va_uid;
        inode->i_gid        = vap->va_gid;
        inode->i_blocks     = vap->va_nblocks;
        inode->i_mtime      = vap->va_mtime;
        inode->i_ctime      = vap->va_ctime;
        if (vap->va_xflags & XFS_XFLAG_IMMUTABLE)
                inode->i_flags |= S_IMMUTABLE;
        else
                inode->i_flags &= ~S_IMMUTABLE;
        if (vap->va_xflags & XFS_XFLAG_APPEND)
                inode->i_flags |= S_APPEND;
        else
                inode->i_flags &= ~S_APPEND;
        if (vap->va_xflags & XFS_XFLAG_SYNC)
                inode->i_flags |= S_SYNC;
        else
                inode->i_flags &= ~S_SYNC;
        if (vap->va_xflags & XFS_XFLAG_NOATIME)
                inode->i_flags |= S_NOATIME;
        else
                inode->i_flags &= ~S_NOATIME;
}

/*
 * Revalidate the Linux inode from the vnode.
 */
int
__vn_revalidate(
        bhv_vnode_t     *vp,
        bhv_vattr_t     *vattr)
{
        int             error;

        vn_trace_entry(xfs_vtoi(vp), __FUNCTION__, (inst_t *)__return_address);
        vattr->va_mask = XFS_AT_STAT | XFS_AT_XFLAGS;
        error = xfs_getattr(xfs_vtoi(vp), vattr, 0);
        if (likely(!error)) {
                vn_revalidate_core(vp, vattr);
                xfs_iflags_clear(xfs_vtoi(vp), XFS_IMODIFIED);
        }
        return -error;
}

int
vn_revalidate(
        bhv_vnode_t     *vp)
{
        bhv_vattr_t     vattr;

        return __vn_revalidate(vp, &vattr);
}

/*
 * Add a reference to a referenced vnode.
 */
bhv_vnode_t *
vn_hold(
        bhv_vnode_t     *vp)
{
        struct inode    *inode;

        XFS_STATS_INC(vn_hold);

        inode = igrab(vn_to_inode(vp));
        ASSERT(inode);

        return vp;
}

#ifdef  XFS_VNODE_TRACE

/*
 * Reference count of Linux inode if present, -1 if the xfs_inode
 * has no associated Linux inode.
 */
static inline int xfs_icount(struct xfs_inode *ip)
{
        bhv_vnode_t *vp = XFS_ITOV_NULL(ip);

        if (vp)
                return vn_count(vp);
        return -1;
}

#define KTRACE_ENTER(ip, vk, s, line, ra)                       \
        ktrace_enter(   (ip)->i_trace,                          \
/*  0 */                (void *)(__psint_t)(vk),                \
/*  1 */                (void *)(s),                            \
/*  2 */                (void *)(__psint_t) line,               \
/*  3 */                (void *)(__psint_t)xfs_icount(ip),      \
/*  4 */                (void *)(ra),                           \
/*  5 */                NULL,                                   \
/*  6 */                (void *)(__psint_t)current_cpu(),       \
/*  7 */                (void *)(__psint_t)current_pid(),       \
/*  8 */                (void *)__return_address,               \
/*  9 */                NULL, NULL, NULL, NULL, NULL, NULL, NULL)

/*
 * Vnode tracing code.
 */
void
vn_trace_entry(xfs_inode_t *ip, const char *func, inst_t *ra)
{
        KTRACE_ENTER(ip, VNODE_KTRACE_ENTRY, func, 0, ra);
}

void
vn_trace_exit(xfs_inode_t *ip, const char *func, inst_t *ra)
{
        KTRACE_ENTER(ip, VNODE_KTRACE_EXIT, func, 0, ra);
}

void
vn_trace_hold(xfs_inode_t *ip, char *file, int line, inst_t *ra)
{
        KTRACE_ENTER(ip, VNODE_KTRACE_HOLD, file, line, ra);
}

void
vn_trace_ref(xfs_inode_t *ip, char *file, int line, inst_t *ra)
{
        KTRACE_ENTER(ip, VNODE_KTRACE_REF, file, line, ra);
}

void
vn_trace_rele(xfs_inode_t *ip, char *file, int line, inst_t *ra)
{
        KTRACE_ENTER(ip, VNODE_KTRACE_RELE, file, line, ra);
}
#endif  /* XFS_VNODE_TRACE */