usr/src/sys/ufs/mfs/mfs_vnops.c

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)mfs_vnops.c 7.38 (Berkeley) %G%
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/map.h>
#include <sys/vnode.h>
#include <sys/malloc.h>

#include <miscfs/specfs/specdev.h>

#include <machine/vmparam.h>

#include <ufs/mfs/mfsnode.h>
#include <ufs/mfs/mfsiom.h>
#include <ufs/mfs/mfs_extern.h>

#if !defined(hp300) && !defined(i386) && !defined(mips) && !defined(sparc) && !defined(luna68k)
static int mfsmap_want;         /* 1 => need kernel I/O resources */
struct map mfsmap[MFS_MAPSIZE];
extern char mfsiobuf[];
#endif

/*
 * mfs vnode operations.
 */
int (**mfs_vnodeop_p)();
struct vnodeopv_entry_desc mfs_vnodeop_entries[] = {
        { &vop_default_desc, vn_default_error },
        { &vop_lookup_desc, mfs_lookup },               /* lookup */
        { &vop_create_desc, mfs_create },               /* create */
        { &vop_mknod_desc, mfs_mknod },                 /* mknod */
        { &vop_open_desc, mfs_open },                   /* open */
        { &vop_close_desc, mfs_close },                 /* close */
        { &vop_access_desc, mfs_access },               /* access */
        { &vop_getattr_desc, mfs_getattr },             /* getattr */
        { &vop_setattr_desc, mfs_setattr },             /* setattr */
        { &vop_read_desc, mfs_read },                   /* read */
        { &vop_write_desc, mfs_write },                 /* write */
        { &vop_ioctl_desc, mfs_ioctl },                 /* ioctl */
        { &vop_select_desc, mfs_select },               /* select */
        { &vop_mmap_desc, mfs_mmap },                   /* mmap */
        { &vop_fsync_desc, spec_fsync },                /* fsync */
        { &vop_seek_desc, mfs_seek },                   /* seek */
        { &vop_remove_desc, mfs_remove },               /* remove */
        { &vop_link_desc, mfs_link },                   /* link */
        { &vop_rename_desc, mfs_rename },               /* rename */
        { &vop_mkdir_desc, mfs_mkdir },                 /* mkdir */
        { &vop_rmdir_desc, mfs_rmdir },                 /* rmdir */
        { &vop_symlink_desc, mfs_symlink },             /* symlink */
        { &vop_readdir_desc, mfs_readdir },             /* readdir */
        { &vop_readlink_desc, mfs_readlink },           /* readlink */
        { &vop_abortop_desc, mfs_abortop },             /* abortop */
        { &vop_inactive_desc, mfs_inactive },           /* inactive */
        { &vop_reclaim_desc, mfs_reclaim },             /* reclaim */
        { &vop_lock_desc, mfs_lock },                   /* lock */
        { &vop_unlock_desc, mfs_unlock },               /* unlock */
        { &vop_bmap_desc, mfs_bmap },                   /* bmap */
        { &vop_strategy_desc, mfs_strategy },           /* strategy */
        { &vop_print_desc, mfs_print },                 /* print */
        { &vop_islocked_desc, mfs_islocked },           /* islocked */
        { &vop_advlock_desc, mfs_advlock },             /* advlock */
        { &vop_blkatoff_desc, mfs_blkatoff },           /* blkatoff */
        { &vop_valloc_desc, mfs_valloc },               /* valloc */
        { &vop_vfree_desc, mfs_vfree },                 /* vfree */
        { &vop_truncate_desc, mfs_truncate },           /* truncate */
        { &vop_update_desc, mfs_update },               /* update */
        { &vop_bwrite_desc, mfs_bwrite },               /* bwrite */
        { (struct vnodeop_desc*)NULL, (int(*)())NULL }
};
struct vnodeopv_desc mfs_vnodeop_opv_desc =
        { &mfs_vnodeop_p, mfs_vnodeop_entries };

/*
 * Vnode Operations.
 *
 * Open called to allow memory filesystem to initialize and
 * validate before actual IO. Record our process identifier
 * so we can tell when we are doing I/O to ourself.
 */
/* ARGSUSED */
int
mfs_open(ap)
        struct vop_open_args /* {
                struct vnode *a_vp;
                int  a_mode;
                struct ucred *a_cred;
                struct proc *a_p;
        } */ *ap;
{

        if (ap->a_vp->v_type != VBLK) {
                panic("mfs_ioctl not VBLK");
                /* NOTREACHED */
        }
        return (0);
}

/*
 * Ioctl operation.
 */
/* ARGSUSED */
int
mfs_ioctl(ap)
        struct vop_ioctl_args /* {
                struct vnode *a_vp;
                int  a_command;
                caddr_t  a_data;
                int  a_fflag;
                struct ucred *a_cred;
                struct proc *a_p;
        } */ *ap;
{

        return (ENOTTY);
}

/*
 * Pass I/O requests to the memory filesystem process.
 */
int
mfs_strategy(ap)
        struct vop_strategy_args /* {
                struct buf *a_bp;
        } */ *ap;
{
        register struct buf *bp = ap->a_bp;
        register struct mfsnode *mfsp;
        struct vnode *vp;
        struct proc *p = curproc;               /* XXX */

        if (vfinddev(bp->b_dev, VBLK, &vp) || vp->v_usecount == 0)
                panic("mfs_strategy: bad dev");
        mfsp = VTOMFS(vp);
        /* check for mini-root access */
        if (mfsp->mfs_pid == 0) {
                caddr_t base;

                base = mfsp->mfs_baseoff + (bp->b_blkno << DEV_BSHIFT);
                if (bp->b_flags & B_READ)
                        bcopy(base, bp->b_un.b_addr, bp->b_bcount);
                else
                        bcopy(bp->b_un.b_addr, base, bp->b_bcount);
                biodone(bp);
        } else if (mfsp->mfs_pid == p->p_pid) {
                mfs_doio(bp, mfsp->mfs_baseoff);
        } else {
                bp->av_forw = mfsp->mfs_buflist;
                mfsp->mfs_buflist = bp;
                wakeup((caddr_t)vp);
        }
        return (0);
}

#if defined(vax) || defined(tahoe)
/*
 * Memory file system I/O.
 *
 * Essentially play ubasetup() and disk interrupt service routine by
 * doing the copies to or from the memfs process. If doing physio
 * (i.e. pagein), we must map the I/O through the kernel virtual
 * address space.
 */
void
mfs_doio(bp, base)
        register struct buf *bp;
        caddr_t base;
{
        register struct pte *pte, *ppte;
        register caddr_t vaddr;
        int off, npf, npf2, reg;
        caddr_t kernaddr, offset;

        /*
         * For phys I/O, map the b_addr into kernel virtual space using
         * the Mfsiomap pte's.
         */
        if ((bp->b_flags & B_PHYS) == 0) {
                kernaddr = bp->b_un.b_addr;
        } else {
                if (bp->b_flags & (B_PAGET | B_UAREA | B_DIRTY))
                        panic("swap on memfs?");
                off = (int)bp->b_un.b_addr & PGOFSET;
                npf = btoc(bp->b_bcount + off);
                /*
                 * Get some mapping page table entries
                 */
                while ((reg = rmalloc(mfsmap, (long)npf)) == 0) {
                        mfsmap_want++;
                        sleep((caddr_t)&mfsmap_want, PZERO-1);
                }
                reg--;
                pte = vtopte(bp->b_proc, btop(bp->b_un.b_addr));
                /*
                 * Do vmaccess() but with the Mfsiomap page table.
                 */
                ppte = &Mfsiomap[reg];
                vaddr = &mfsiobuf[reg * NBPG];
                kernaddr = vaddr + off;
                for (npf2 = npf; npf2; npf2--) {
                        mapin(ppte, (u_int)vaddr, pte->pg_pfnum,
                                (int)(PG_V|PG_KW));
#if defined(tahoe)
                        if ((bp->b_flags & B_READ) == 0)
                                mtpr(P1DC, vaddr);
#endif
                        ppte++;
                        pte++;
                        vaddr += NBPG;
                }
        }
        offset = base + (bp->b_blkno << DEV_BSHIFT);
        if (bp->b_flags & B_READ)
                bp->b_error = copyin(offset, kernaddr, bp->b_bcount);
        else
                bp->b_error = copyout(kernaddr, offset, bp->b_bcount);
        if (bp->b_error)
                bp->b_flags |= B_ERROR;
        /*
         * Release pte's used by physical I/O.
         */
        if (bp->b_flags & B_PHYS) {
                rmfree(mfsmap, (long)npf, (long)++reg);
                if (mfsmap_want) {
                        mfsmap_want = 0;
                        wakeup((caddr_t)&mfsmap_want);
                }
        }
        biodone(bp);
}
#endif  /* vax || tahoe */

#if defined(hp300) || defined(i386) || defined(mips) || defined(sparc) || defined(luna68k)
/*
 * Memory file system I/O.
 *
 * Trivial on the HP since buffer has already been mapping into KVA space.
 */
void
mfs_doio(bp, base)
        register struct buf *bp;
        caddr_t base;
{

        base += (bp->b_blkno << DEV_BSHIFT);
        if (bp->b_flags & B_READ)
                bp->b_error = copyin(base, bp->b_un.b_addr, bp->b_bcount);
        else
                bp->b_error = copyout(bp->b_un.b_addr, base, bp->b_bcount);
        if (bp->b_error)
                bp->b_flags |= B_ERROR;
        biodone(bp);
}
#endif

/*
 * This is a noop, simply returning what one has been given.
 */
int
mfs_bmap(ap)
        struct vop_bmap_args /* {
                struct vnode *a_vp;
                daddr_t  a_bn;
                struct vnode **a_vpp;
                daddr_t *a_bnp;
        } */ *ap;
{

        if (ap->a_vpp != NULL)
                *ap->a_vpp = ap->a_vp;
        if (ap->a_bnp != NULL)
                *ap->a_bnp = ap->a_bn;
        return (0);
}

/*
 * Memory filesystem close routine
 */
/* ARGSUSED */
int
mfs_close(ap)
        struct vop_close_args /* {
                struct vnode *a_vp;
                int  a_fflag;
                struct ucred *a_cred;
                struct proc *a_p;
        } */ *ap;
{
        register struct vnode *vp = ap->a_vp;
        register struct mfsnode *mfsp = VTOMFS(vp);
        register struct buf *bp;
        int error;

        /*
         * Finish any pending I/O requests.
         */
        while (bp = mfsp->mfs_buflist) {
                mfsp->mfs_buflist = bp->av_forw;
                mfs_doio(bp, mfsp->mfs_baseoff);
                wakeup((caddr_t)bp);
        }
        /*
         * On last close of a memory filesystem
         * we must invalidate any in core blocks, so that
         * we can, free up its vnode.
         */
        if (error = vinvalbuf(vp, 1, ap->a_cred, ap->a_p))
                return (error);
        /*
         * There should be no way to have any more uses of this
         * vnode, so if we find any other uses, it is a panic.
         */
        if (vp->v_usecount > 1)
                printf("mfs_close: ref count %d > 1\n", vp->v_usecount);
        if (vp->v_usecount > 1 || mfsp->mfs_buflist)
                panic("mfs_close");
        /*
         * Send a request to the filesystem server to exit.
         */
        mfsp->mfs_buflist = (struct buf *)(-1);
        wakeup((caddr_t)vp);
        return (0);
}

/*
 * Memory filesystem inactive routine
 */
/* ARGSUSED */
int
mfs_inactive(ap)
        struct vop_inactive_args /* {
                struct vnode *a_vp;
        } */ *ap;
{
        register struct mfsnode *mfsp = VTOMFS(ap->a_vp);

        if (mfsp->mfs_buflist && mfsp->mfs_buflist != (struct buf *)(-1))
                panic("mfs_inactive: not inactive (mfs_buflist %x)",
                        mfsp->mfs_buflist);
        return (0);
}

/*
 * Reclaim a memory filesystem devvp so that it can be reused.
 */
int
mfs_reclaim(ap)
        struct vop_reclaim_args /* {
                struct vnode *a_vp;
        } */ *ap;
{

        FREE(ap->a_vp->v_data, M_MFSNODE);
        ap->a_vp->v_data = NULL;
        return (0);
}

/*
 * Print out the contents of an mfsnode.
 */
int
mfs_print(ap)
        struct vop_print_args /* {
                struct vnode *a_vp;
        } */ *ap;
{
        register struct mfsnode *mfsp = VTOMFS(ap->a_vp);

        printf("tag VT_MFS, pid %d, base %d, size %d\n", mfsp->mfs_pid,
                mfsp->mfs_baseoff, mfsp->mfs_size);
        return (0);
}

/*
 * Block device bad operation
 */
int
mfs_badop()
{

        panic("mfs_badop called\n");
        /* NOTREACHED */
}

/*
 * Memory based filesystem initialization.
 */
mfs_init()
{

#if !defined(hp300) && !defined(i386) && !defined(mips) && !defined(sparc) && !defined(luna68k)
        rminit(mfsmap, (long)MFS_MAPREG, (long)1, "mfs mapreg", MFS_MAPSIZE);
#endif
}