printf(1): don't use getopt, second take

[dragonfly.git] / sys / vfs / mfs / mfs_vnops.c

/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``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.
 *
 *      @(#)mfs_vnops.c 8.11 (Berkeley) 5/22/95
 * $FreeBSD: src/sys/ufs/mfs/mfs_vnops.c,v 1.47.2.1 2001/05/22 02:06:43 bp Exp $
 * $DragonFly: src/sys/vfs/mfs/mfs_vnops.c,v 1.37 2007/08/13 17:31:56 dillon Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <sys/sysproto.h>
#include <sys/mman.h>
#include <sys/conf.h>

#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
#include <vm/vnode_pager.h>

#include <sys/buf2.h>
#include <sys/thread2.h>

#include "mfsnode.h"
#include "mfs_extern.h"

static int      mfs_badop (struct vop_generic_args *);
static int      mfs_bmap (struct vop_bmap_args *);
static int      mfs_close (struct vop_close_args *);
static int      mfs_fsync (struct vop_fsync_args *);
static int      mfs_freeblks (struct vop_freeblks_args *);
static int      mfs_inactive (struct vop_inactive_args *); /* XXX */
static int      mfs_open (struct vop_open_args *);
static int      mfs_reclaim (struct vop_reclaim_args *); /* XXX */
static int      mfs_print (struct vop_print_args *); /* XXX */
static int      mfs_strategy (struct vop_strategy_args *); /* XXX */
/*
 * mfs vnode operations.  Note: the vops here are used for the MFS block
 * device, not for operations on files (MFS calls the ffs mount code for that)
 */
static struct vop_ops mfs_vnode_vops = {
        .vop_default =          mfs_badop,
        .vop_bmap =             mfs_bmap,
        .vop_close =            mfs_close,
        .vop_freeblks =         mfs_freeblks,
        .vop_fsync =            mfs_fsync,
        .vop_inactive =         mfs_inactive,
        .vop_ioctl =            (void *)vop_enotty,
        .vop_open =             mfs_open,
        .vop_print =            mfs_print,
        .vop_reclaim =          mfs_reclaim,
        .vop_strategy =         mfs_strategy,
};

struct vop_ops *mfs_vnode_vops_p = &mfs_vnode_vops;

VNODEOP_SET(mfs_vnode_vops);

/*
 * 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.
 *
 * NOTE: new device sequencing.  mounts check the device reference count
 * before calling open, so we must associate the device in open and 
 * disassociate it in close rather then faking it when we created the vnode.
 *
 * mfs_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred,
 *          struct file *a_fp)
 */
/* ARGSUSED */
static int
mfs_open(struct vop_open_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct mfsnode *mfsp = VTOMFS(vp);

        if (vp->v_type != VCHR)
                panic("mfs_open not VCHR");
        if (vp->v_rdev == NULL)
                v_associate_rdev(vp, mfsp->mfs_dev);
        return (vop_stdopen(ap));
}

static int
mfs_fsync(struct vop_fsync_args *ap)
{
        return (0);
}

/*
 * mfs_freeblks() - hook to allow us to free physical memory.
 *
 *      We implement the BUF_CMD_FREEBLKS strategy.  We can't just madvise()
 *      here because we have to do it in the correct order vs other bio
 *      requests, so we queue it.
 *
 *      Note: geteblk() sets B_INVAL.  We leave it set to guarentee buffer
 *      throw-away on brelse()? XXX
 *
 * mfs_freeblks(struct vnode *a_vp, daddr_t a_addr, daddr_t a_length)
 */
static int
mfs_freeblks(struct vop_freeblks_args *ap)
{       
        struct buf *bp;
        struct vnode *vp = ap->a_vp;

        bp = geteblk(ap->a_length);
        bp->b_cmd = BUF_CMD_FREEBLKS;
        bp->b_bio1.bio_offset = ap->a_offset;
        bp->b_bcount = ap->a_length;
        BUF_KERNPROC(bp);
        vn_strategy(vp, &bp->b_bio1);
        return(0);
}

/*
 * Pass I/O requests to the memory filesystem process.
 *
 * mfs_strategy(struct vnode *a_vp, struct bio *a_bio)
 */
static int
mfs_strategy(struct vop_strategy_args *ap)
{
        struct bio *bio = ap->a_bio;
        struct buf *bp = bio->bio_buf;
        struct mfsnode *mfsp;
        struct thread *td = curthread;          /* XXX */

        mfsp = ap->a_vp->v_rdev->si_drv1;
        if (mfsp == NULL) {
                bp->b_error = ENXIO;
                bp->b_flags |= B_ERROR;
                biodone(bio);
                return(0);
        }

        /*
         * splbio required for queueing/dequeueing, in case of forwarded
         * BPs from bio interrupts (?).  It may not be necessary.
         */

        crit_enter();

        if (mfsp->mfs_td == NULL) {
                /*
                 * mini-root.  Note: BUF_CMD_FREEBLKS not supported at the
                 * moment, since we do not know what kind of dataspace
                 * b_data is in.
                 */
                caddr_t base;

                base = mfsp->mfs_baseoff + bio->bio_offset;
                switch(bp->b_cmd) {
                case BUF_CMD_FREEBLKS:
                        break;
                case BUF_CMD_READ:
                        bcopy(base, bp->b_data, bp->b_bcount);
                        break;
                case BUF_CMD_WRITE:
                        bcopy(bp->b_data, base, bp->b_bcount);
                        break;
                default:
                        panic("mfs: bad b_cmd %d\n", bp->b_cmd);
                }
                biodone(bio);
        } else if (mfsp->mfs_td == td) {
                /*
                 * VOP to self
                 */
                crit_exit();
                mfs_doio(bio, mfsp);
                crit_enter();
        } else {
                /*
                 * VOP from some other process, queue to MFS process and
                 * wake it up.
                 */
                bioq_insert_tail(&mfsp->bio_queue, bio);
                wakeup((caddr_t)mfsp);
        }
        crit_exit();
        return (0);
}

/*
 * Memory file system I/O.
 *
 * Trivial on the HP since buffer has already been mapping into KVA space.
 *
 * Read and Write are handled with a simple copyin and copyout.    
 *
 * We also partially support VOP_FREEBLKS().  We can't implement
 * completely -- for example, on fragments or inode metadata, but we can
 * implement it for page-aligned requests.
 */
void
mfs_doio(struct bio *bio, struct mfsnode *mfsp)
{
        struct buf *bp = bio->bio_buf;
        caddr_t base = mfsp->mfs_baseoff + bio->bio_offset;
        int bytes;

        switch(bp->b_cmd) {
        case BUF_CMD_FREEBLKS:
                /*
                 * Implement FREEBLKS, which allows the filesystem to tell
                 * a block device when blocks are no longer needed (like when
                 * a file is deleted).  We use the hook to MADV_FREE the VM.
                 * This makes an MFS filesystem work as well or better then
                 * a sun-style swap-mounted filesystem.
                 */
                bytes = bp->b_bcount;

                if ((vm_offset_t)base & PAGE_MASK) {
                        int n = PAGE_SIZE - ((vm_offset_t)base & PAGE_MASK);
                        bytes -= n;
                        base += n;
                }
                if (bytes > 0) {
                        struct madvise_args uap;

                        bytes &= ~PAGE_MASK;
                        if (bytes != 0) {
                                bzero(&uap, sizeof(uap));
                                uap.addr  = base;
                                uap.len   = bytes;
                                uap.behav = MADV_FREE;
                                sys_madvise(&uap);
                        }
                }
                bp->b_error = 0;
                break;
        case BUF_CMD_READ:
                /*
                 * Read data from our 'memory' disk
                 */
                bp->b_error = copyin(base, bp->b_data, bp->b_bcount);
                break;
        case BUF_CMD_WRITE:
                /*
                 * Write data to our 'memory' disk
                 */
                bp->b_error = copyout(bp->b_data, base, bp->b_bcount);
                break;
        default:
                panic("mfs: bad b_cmd %d\n", bp->b_cmd);
        }
        if (bp->b_error)
                bp->b_flags |= B_ERROR;
        biodone(bio);
}

/*
 * This is a noop, simply returning what one has been given.
 *
 * mfs_bmap(struct vnode *a_vp, off_t a_loffset,
 *          off_t *a_doffsetp, int *a_runp, int *a_runb)
 */
static int
mfs_bmap(struct vop_bmap_args *ap)
{
        if (ap->a_doffsetp != NULL)
                *ap->a_doffsetp = ap->a_loffset;
        if (ap->a_runp != NULL)
                *ap->a_runp = 0;
        if (ap->a_runb != NULL)
                *ap->a_runb = 0;
        return (0);
}

/*
 * Memory filesystem close routine
 *
 * mfs_close(struct vnode *a_vp, int a_fflag)
 */
/* ARGSUSED */
static int
mfs_close(struct vop_close_args *ap)
{
        struct vnode *vp = ap->a_vp;
        struct mfsnode *mfsp = VTOMFS(vp);
        struct bio *bio;
        int error = 0;

        /*
         * Finish any pending I/O requests.
         */
        while ((bio = bioq_first(&mfsp->bio_queue)) != NULL) {
                bioq_remove(&mfsp->bio_queue, bio);
                mfs_doio(bio, mfsp);
                wakeup((caddr_t)bio->bio_buf);
        }

        /*
         * We really only care about the last close
         */
        if (vp->v_opencount > 1)
                goto done;

        /*
         * Synchronize any remaining buffers and then destroy them.
         */
        if ((error = vinvalbuf(vp, V_SAVE, 0, 0)) != 0)
                goto done;

        /*
         * Get rid of the pseudo-backing object.  Since the object is
         * not directly memory mapped, we don't have to worry about 
         * synchronizing it.
         */
        if (vp->v_object)
                vm_pager_deallocate(vp->v_object);

        /*
         * 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_sysref.refcnt > 1)
                kprintf("mfs_close: ref count %d > 1\n", vp->v_sysref.refcnt);
        if (vp->v_sysref.refcnt > 1 || (bioq_first(&mfsp->bio_queue) != NULL))
                panic("mfs_close");
        /*
         * Send a request to the filesystem server to exit.
         */
        mfsp->mfs_active = 0;
        v_release_rdev(vp);
        if (mfsp->mfs_dev) {
                destroy_dev(mfsp->mfs_dev);
                mfsp->mfs_dev = NULL;
        }
        wakeup((caddr_t)mfsp);
done:
        vop_stdclose(ap);
        return (error);
}

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

        if (bioq_first(&mfsp->bio_queue) != NULL)
                panic("mfs_inactive: not inactive (next buffer %p)",
                        bioq_first(&mfsp->bio_queue));
        return (0);
}

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

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

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

        kprintf("tag VT_MFS, td %p, base %p, size %ld\n",
            mfsp->mfs_td, (void *)mfsp->mfs_baseoff, mfsp->mfs_size);
        return (0);
}

/*
 * Block device bad operation
 */
static int
mfs_badop(struct vop_generic_args *ap)
{
        int i;

        kprintf("mfs_badop[%s]\n", ap->a_desc->sd_name);
        i = vop_defaultop(ap);
        kprintf("mfs_badop[%s] = %d\n", ap->a_desc->sd_name, i);
        return (i);
}