]> git.saurik.com Git - apple/xnu.git/blobdiff - bsd/miscfs/specfs/spec_vnops.c
xnu-792.12.6.tar.gz
[apple/xnu.git] / bsd / miscfs / specfs / spec_vnops.c
index 81b836085dc1b5cb8bdc9531a07acb3507543514..54ff81586ab5fa11f47f11aecd9d45e1d902eb9b 100644 (file)
@@ -1,23 +1,31 @@
 /*
- * Copyright (c) 2000-2001 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
  * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * This file contains Original Code and/or Modifications of Original Code 
+ * as defined in and that are subject to the Apple Public Source License 
+ * Version 2.0 (the 'License'). You may not use this file except in 
+ * compliance with the License.  The rights granted to you under the 
+ * License may not be used to create, or enable the creation or 
+ * redistribution of, unlawful or unlicensed copies of an Apple operating 
+ * system, or to circumvent, violate, or enable the circumvention or 
+ * violation of, any terms of an Apple operating system software license 
+ * agreement.
+ *
+ * Please obtain a copy of the License at 
+ * http://www.opensource.apple.com/apsl/ and read it before using this 
+ * file.
+ *
+ * The Original Code and all software distributed under the License are 
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
+ * Please see the License for the specific language governing rights and 
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  */
 /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
 /*
  */
 
 #include <sys/param.h>
-#include <sys/proc.h>
+#include <sys/proc_internal.h>
+#include <sys/kauth.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
 #include <sys/conf.h>
-#include <sys/buf.h>
-#include <sys/mount.h>
+#include <sys/buf_internal.h>
+#include <sys/mount_internal.h>
 #include <sys/namei.h>
-#include <sys/vnode.h>
+#include <sys/vnode_internal.h>
 #include <sys/stat.h>
 #include <sys/errno.h>
 #include <sys/ioctl.h>
 #include <sys/file.h>
+#include <sys/user.h>
 #include <sys/malloc.h>
-#include <dev/disk.h>
+#include <sys/disk.h>
+#include <sys/uio_internal.h>
 #include <miscfs/specfs/specdev.h>
 #include <vfs/vfs_support.h>
 
+#include <sys/kdebug.h>
 
 struct vnode *speclisth[SPECHSZ];
 
@@ -89,70 +101,62 @@ char       devcls[] = "devcls";
 
 int (**spec_vnodeop_p)(void *);
 struct vnodeopv_entry_desc spec_vnodeop_entries[] = {
-       { &vop_default_desc, (VOPFUNC)vn_default_error },
-       { &vop_lookup_desc, (VOPFUNC)spec_lookup },             /* lookup */
-       { &vop_create_desc, (VOPFUNC)err_create },              /* create */
-       { &vop_mknod_desc, (VOPFUNC)err_mknod },                /* mknod */
-       { &vop_open_desc, (VOPFUNC)spec_open },                 /* open */
-       { &vop_close_desc, (VOPFUNC)spec_close },               /* close */
-       { &vop_access_desc, (VOPFUNC)spec_access },             /* access */
-       { &vop_getattr_desc, (VOPFUNC)spec_getattr },           /* getattr */
-       { &vop_setattr_desc, (VOPFUNC)spec_setattr },           /* setattr */
-       { &vop_read_desc, (VOPFUNC)spec_read },                 /* read */
-       { &vop_write_desc, (VOPFUNC)spec_write },               /* write */
-       { &vop_lease_desc, (VOPFUNC)nop_lease },                /* lease */
-       { &vop_ioctl_desc, (VOPFUNC)spec_ioctl },               /* ioctl */
-       { &vop_select_desc, (VOPFUNC)spec_select },             /* select */
-       { &vop_revoke_desc, (VOPFUNC)nop_revoke },              /* revoke */
-       { &vop_mmap_desc, (VOPFUNC)err_mmap },                  /* mmap */
-       { &vop_fsync_desc, (VOPFUNC)spec_fsync },               /* fsync */
-       { &vop_seek_desc, (VOPFUNC)err_seek },                  /* seek */
-       { &vop_remove_desc, (VOPFUNC)err_remove },              /* remove */
-       { &vop_link_desc, (VOPFUNC)err_link },                  /* link */
-       { &vop_rename_desc, (VOPFUNC)err_rename },              /* rename */
-       { &vop_mkdir_desc, (VOPFUNC)err_mkdir },                /* mkdir */
-       { &vop_rmdir_desc, (VOPFUNC)err_rmdir },                /* rmdir */
-       { &vop_symlink_desc, (VOPFUNC)err_symlink },            /* symlink */
-       { &vop_readdir_desc, (VOPFUNC)err_readdir },            /* readdir */
-       { &vop_readlink_desc, (VOPFUNC)err_readlink },          /* readlink */
-       { &vop_abortop_desc, (VOPFUNC)err_abortop },            /* abortop */
-       { &vop_inactive_desc, (VOPFUNC)nop_inactive },          /* inactive */
-       { &vop_reclaim_desc, (VOPFUNC)nop_reclaim },            /* reclaim */
-       { &vop_lock_desc, (VOPFUNC)nop_lock },                  /* lock */
-       { &vop_unlock_desc, (VOPFUNC)nop_unlock },              /* unlock */
-       { &vop_bmap_desc, (VOPFUNC)spec_bmap },                 /* bmap */
-       { &vop_strategy_desc, (VOPFUNC)spec_strategy },         /* strategy */
-       { &vop_print_desc, (VOPFUNC)spec_print },               /* print */
-       { &vop_islocked_desc, (VOPFUNC)nop_islocked },          /* islocked */
-       { &vop_pathconf_desc, (VOPFUNC)spec_pathconf },         /* pathconf */
-       { &vop_advlock_desc, (VOPFUNC)err_advlock },            /* advlock */
-       { &vop_blkatoff_desc, (VOPFUNC)err_blkatoff },          /* blkatoff */
-       { &vop_valloc_desc, (VOPFUNC)err_valloc },              /* valloc */
-       { &vop_vfree_desc, (VOPFUNC)err_vfree },                /* vfree */
-       { &vop_truncate_desc, (VOPFUNC)nop_truncate },          /* truncate */
-       { &vop_update_desc, (VOPFUNC)nop_update },              /* update */
-       { &vop_bwrite_desc, (VOPFUNC)spec_bwrite },             /* bwrite */
-       { &vop_devblocksize_desc, (VOPFUNC)spec_devblocksize }, /* devblocksize */
-       { &vop_pagein_desc, (VOPFUNC)err_pagein },              /* Pagein */
-       { &vop_pageout_desc, (VOPFUNC)err_pageout },            /* Pageout */
-        { &vop_copyfile_desc, (VOPFUNC)err_copyfile },         /* Copyfile */
-       { &vop_blktooff_desc, (VOPFUNC)spec_blktooff },         /* blktooff */
-       { &vop_offtoblk_desc, (VOPFUNC)spec_offtoblk },         /* offtoblk */
-       { &vop_cmap_desc, (VOPFUNC)spec_cmap },         /* cmap */
+       { &vnop_default_desc, (VOPFUNC)vn_default_error },
+       { &vnop_lookup_desc, (VOPFUNC)spec_lookup },            /* lookup */
+       { &vnop_create_desc, (VOPFUNC)err_create },             /* create */
+       { &vnop_mknod_desc, (VOPFUNC)err_mknod },               /* mknod */
+       { &vnop_open_desc, (VOPFUNC)spec_open },                        /* open */
+       { &vnop_close_desc, (VOPFUNC)spec_close },              /* close */
+       { &vnop_access_desc, (VOPFUNC)spec_access },            /* access */
+       { &vnop_getattr_desc, (VOPFUNC)spec_getattr },          /* getattr */
+       { &vnop_setattr_desc, (VOPFUNC)spec_setattr },          /* setattr */
+       { &vnop_read_desc, (VOPFUNC)spec_read },                        /* read */
+       { &vnop_write_desc, (VOPFUNC)spec_write },              /* write */
+       { &vnop_ioctl_desc, (VOPFUNC)spec_ioctl },              /* ioctl */
+       { &vnop_select_desc, (VOPFUNC)spec_select },            /* select */
+       { &vnop_revoke_desc, (VOPFUNC)nop_revoke },             /* revoke */
+       { &vnop_mmap_desc, (VOPFUNC)err_mmap },                 /* mmap */
+       { &vnop_fsync_desc, (VOPFUNC)spec_fsync },              /* fsync */
+       { &vnop_remove_desc, (VOPFUNC)err_remove },             /* remove */
+       { &vnop_link_desc, (VOPFUNC)err_link },                 /* link */
+       { &vnop_rename_desc, (VOPFUNC)err_rename },             /* rename */
+       { &vnop_mkdir_desc, (VOPFUNC)err_mkdir },               /* mkdir */
+       { &vnop_rmdir_desc, (VOPFUNC)err_rmdir },               /* rmdir */
+       { &vnop_symlink_desc, (VOPFUNC)err_symlink },           /* symlink */
+       { &vnop_readdir_desc, (VOPFUNC)err_readdir },           /* readdir */
+       { &vnop_readlink_desc, (VOPFUNC)err_readlink },         /* readlink */
+       { &vnop_inactive_desc, (VOPFUNC)nop_inactive },         /* inactive */
+       { &vnop_reclaim_desc, (VOPFUNC)nop_reclaim },           /* reclaim */
+       { &vnop_strategy_desc, (VOPFUNC)spec_strategy },                /* strategy */
+       { &vnop_pathconf_desc, (VOPFUNC)spec_pathconf },                /* pathconf */
+       { &vnop_advlock_desc, (VOPFUNC)err_advlock },           /* advlock */
+       { &vnop_bwrite_desc, (VOPFUNC)spec_bwrite },            /* bwrite */
+       { &vnop_devblocksize_desc, (VOPFUNC)spec_devblocksize }, /* devblocksize */
+       { &vnop_pagein_desc, (VOPFUNC)err_pagein },             /* Pagein */
+       { &vnop_pageout_desc, (VOPFUNC)err_pageout },           /* Pageout */
+        { &vnop_copyfile_desc, (VOPFUNC)err_copyfile },                /* Copyfile */
+       { &vnop_blktooff_desc, (VOPFUNC)spec_blktooff },                /* blktooff */
+       { &vnop_offtoblk_desc, (VOPFUNC)spec_offtoblk },                /* offtoblk */
+       { &vnop_blockmap_desc, (VOPFUNC)spec_blockmap },                /* blockmap */
        { (struct vnodeop_desc*)NULL, (int(*)())NULL }
 };
 struct vnodeopv_desc spec_vnodeop_opv_desc =
        { &spec_vnodeop_p, spec_vnodeop_entries };
 
+
+static void set_blocksize(vnode_t, dev_t);
+
+
 /*
  * Trivial lookup routine that always fails.
  */
 int
 spec_lookup(ap)
-       struct vop_lookup_args /* {
+       struct vnop_lookup_args /* {
                struct vnode *a_dvp;
                struct vnode **a_vpp;
                struct componentname *a_cnp;
+               vfs_context_t a_context;
        } */ *ap;
 {
 
@@ -160,10 +164,10 @@ spec_lookup(ap)
        return (ENOTDIR);
 }
 
-void
+static void
 set_blocksize(struct vnode *vp, dev_t dev)
 {
-    int (*size)();
+    int (*size)(dev_t);
     int rsize;
 
     if ((major(dev) < nblkdev) && (size = bdevsw[major(dev)].d_psize)) {
@@ -185,10 +189,12 @@ set_fsblocksize(struct vnode *vp)
                dev_t dev = (dev_t)vp->v_rdev;
                int maj = major(dev);
 
-               if ((u_int)maj >= nblkdev)
+               if ((u_int)maj >= (u_int)nblkdev)
                        return;
 
+               vnode_lock(vp);
                set_blocksize(vp, dev);
+               vnode_unlock(vp);
        }
 
 }
@@ -197,17 +203,17 @@ set_fsblocksize(struct vnode *vp)
 /*
  * Open a special file.
  */
-/* ARGSUSED */
+int
 spec_open(ap)
-       struct vop_open_args /* {
+       struct vnop_open_args /* {
                struct vnode *a_vp;
                int  a_mode;
-               struct ucred *a_cred;
-               struct proc *a_p;
+               vfs_context_t a_context;
        } */ *ap;
 {
-       struct proc *p = ap->a_p;
-       struct vnode *bvp, *vp = ap->a_vp;
+       struct proc *p = vfs_context_proc(ap->a_context);
+       kauth_cred_t cred = vfs_context_ucred(ap->a_context);
+       struct vnode *vp = ap->a_vp;
        dev_t bdev, dev = (dev_t)vp->v_rdev;
        int maj = major(dev);
        int error;
@@ -221,9 +227,9 @@ spec_open(ap)
        switch (vp->v_type) {
 
        case VCHR:
-               if ((u_int)maj >= nchrdev)
+               if ((u_int)maj >= (u_int)nchrdev)
                        return (ENXIO);
-               if (ap->a_cred != FSCRED && (ap->a_mode & FWRITE)) {
+               if (cred != FSCRED && (ap->a_mode & FWRITE)) {
                        /*
                         * When running in very secure mode, do not allow
                         * opens for writing of any disk character devices.
@@ -237,43 +243,77 @@ spec_open(ap)
                         * currently mounted.
                         */
                        if (securelevel >= 1) {
-                               if ((bdev = chrtoblk(dev)) != NODEV &&
-                                   vfinddev(bdev, VBLK, &bvp) &&
-                                   bvp->v_usecount > 0 &&
-                                   (error = vfs_mountedon(bvp)))
+                               if ((bdev = chrtoblk(dev)) != NODEV && check_mountedon(bdev, VBLK, &error))
                                        return (error);
                                if (iskmemdev(dev))
                                        return (EPERM);
                        }
                }
-               if (cdevsw[maj].d_type == D_TTY)
+               if (cdevsw[maj].d_type == D_TTY) {
+                       vnode_lock(vp);
                        vp->v_flag |= VISTTY;
-               VOP_UNLOCK(vp, 0, p);
+                       vnode_unlock(vp);
+               }
                error = (*cdevsw[maj].d_open)(dev, ap->a_mode, S_IFCHR, p);
-               vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
                return (error);
 
        case VBLK:
-               if ((u_int)maj >= nblkdev)
+               if ((u_int)maj >= (u_int)nblkdev)
                        return (ENXIO);
                /*
                 * When running in very secure mode, do not allow
                 * opens for writing of any disk block devices.
                 */
-               if (securelevel >= 2 && ap->a_cred != FSCRED &&
+               if (securelevel >= 2 && cred != FSCRED &&
                    (ap->a_mode & FWRITE) && bdevsw[maj].d_type == D_DISK)
                        return (EPERM);
                /*
                 * Do not allow opens of block devices that are
                 * currently mounted.
                 */
-               if (error = vfs_mountedon(vp))
+               if ( (error = vfs_mountedon(vp)) )
                        return (error);
                error = (*bdevsw[maj].d_open)(dev, ap->a_mode, S_IFBLK, p);
                if (!error) {
+                   u_int64_t blkcnt;
+                   u_int32_t blksize;
+                       int setsize = 0;
+                       u_int32_t size512 = 512;
+
+
+                   if (!VNOP_IOCTL(vp, DKIOCGETBLOCKSIZE, (caddr_t)&blksize, 0, ap->a_context)) {
+                               /* Switch to 512 byte sectors (temporarily) */
+
+                               if (!VNOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&size512, FWRITE, ap->a_context)) {
+                               /* Get the number of 512 byte physical blocks. */
+                               if (!VNOP_IOCTL(vp, DKIOCGETBLOCKCOUNT, (caddr_t)&blkcnt, 0, ap->a_context)) {
+                                               setsize = 1;
+                               }
+                               }
+                               /* If it doesn't set back, we can't recover */
+                               if (VNOP_IOCTL(vp, DKIOCSETBLOCKSIZE, (caddr_t)&blksize, FWRITE, ap->a_context))
+                               error = ENXIO;
+                   }
+
+
+                       vnode_lock(vp);
                    set_blocksize(vp, dev);
+
+                   /*
+                    * Cache the size in bytes of the block device for later
+                    * use by spec_write().
+                    */
+                       if (setsize)
+                               vp->v_specdevsize = blkcnt * (u_int64_t)size512;
+                       else
+                       vp->v_specdevsize = (u_int64_t)0;       /* Default: Can't get */
+                       
+                       vnode_unlock(vp);
+
                }
                return(error);
+       default:
+               panic("spec_open type");
        }
        return (0);
 }
@@ -281,42 +321,39 @@ spec_open(ap)
 /*
  * Vnode op for read
  */
-/* ARGSUSED */
+int
 spec_read(ap)
-       struct vop_read_args /* {
+       struct vnop_read_args /* {
                struct vnode *a_vp;
                struct uio *a_uio;
                int  a_ioflag;
-               struct ucred *a_cred;
+               vfs_context_t a_context;
        } */ *ap;
 {
        register struct vnode *vp = ap->a_vp;
        register struct uio *uio = ap->a_uio;
-       struct proc *p = uio->uio_procp;
        struct buf *bp;
-       daddr_t bn, nextbn;
+       daddr64_t bn, nextbn;
        long bsize, bscale;
        int devBlockSize=0;
-       int n, on, majordev, (*ioctl)();
+       int n, on;
        int error = 0;
        dev_t dev;
 
 #if DIAGNOSTIC
        if (uio->uio_rw != UIO_READ)
                panic("spec_read mode");
-       if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc())
+       if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg))
                panic("spec_read proc");
 #endif
-       if (uio->uio_resid == 0)
+       if (uio_resid(uio) == 0)
                return (0);
 
        switch (vp->v_type) {
 
        case VCHR:
-               VOP_UNLOCK(vp, 0, p);
                error = (*cdevsw[major(vp->v_rdev)].d_read)
                        (vp->v_rdev, uio, ap->a_ioflag);
-               vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
                return (error);
 
        case VBLK:
@@ -336,55 +373,60 @@ spec_read(ap)
                do {
                        on = uio->uio_offset % bsize;
 
-                       bn = (uio->uio_offset / devBlockSize) &~ (bscale - 1);
+                       bn = (daddr64_t)((uio->uio_offset / devBlockSize) &~ (bscale - 1));
                        
-                       if (vp->v_lastr + bscale == bn) {
+                       if (vp->v_speclastr + bscale == bn) {
                                nextbn = bn + bscale;
-                               error = breadn(vp, bn, (int)bsize, &nextbn,
+                               error = buf_breadn(vp, bn, (int)bsize, &nextbn,
                                               (int *)&bsize, 1, NOCRED, &bp);
                        } else
-                               error = bread(vp, bn, (int)bsize, NOCRED, &bp);
+                               error = buf_bread(vp, bn, (int)bsize, NOCRED, &bp);
+
+                       vnode_lock(vp);
+                       vp->v_speclastr = bn;
+                       vnode_unlock(vp);
 
-                       vp->v_lastr = bn;
-                       n = bsize - bp->b_resid;
+                       n = bsize - buf_resid(bp);
                        if ((on > n) || error) {
                                if (!error)
                                        error = EINVAL;
-                               brelse(bp);
+                               buf_brelse(bp);
                                return (error);
                        }
-                       n = min((unsigned)(n  - on), uio->uio_resid);
+                       // LP64todo - fix this!
+                       n = min((unsigned)(n  - on), uio_resid(uio));
 
-                       error = uiomove((char *)bp->b_data + on, n, uio);
+                       error = uiomove((char *)buf_dataptr(bp) + on, n, uio);
                        if (n + on == bsize)
-                               bp->b_flags |= B_AGE;
-                       brelse(bp);
-               } while (error == 0 && uio->uio_resid > 0 && n != 0);
+                               buf_markaged(bp);
+                       buf_brelse(bp);
+               } while (error == 0 && uio_resid(uio) > 0 && n != 0);
                return (error);
 
        default:
                panic("spec_read type");
        }
        /* NOTREACHED */
+
+       return (0);
 }
 
 /*
  * Vnode op for write
  */
-/* ARGSUSED */
+int
 spec_write(ap)
-       struct vop_write_args /* {
+       struct vnop_write_args /* {
                struct vnode *a_vp;
                struct uio *a_uio;
                int  a_ioflag;
-               struct ucred *a_cred;
+               vfs_context_t a_context;
        } */ *ap;
 {
        register struct vnode *vp = ap->a_vp;
        register struct uio *uio = ap->a_uio;
-       struct proc *p = uio->uio_procp;
        struct buf *bp;
-       daddr_t bn;
+       daddr64_t bn;
        int bsize, blkmask, bscale;
        register int io_sync;
        register int io_size;
@@ -396,27 +438,26 @@ spec_write(ap)
 #if DIAGNOSTIC
        if (uio->uio_rw != UIO_WRITE)
                panic("spec_write mode");
-       if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != current_proc())
+       if (UIO_SEG_IS_USER_SPACE(uio->uio_segflg))
                panic("spec_write proc");
 #endif
 
        switch (vp->v_type) {
 
        case VCHR:
-               VOP_UNLOCK(vp, 0, p);
                error = (*cdevsw[major(vp->v_rdev)].d_write)
                        (vp->v_rdev, uio, ap->a_ioflag);
-               vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
                return (error);
 
        case VBLK:
-               if (uio->uio_resid == 0)
+               if (uio_resid(uio) == 0)
                        return (0);
                if (uio->uio_offset < 0)
                        return (EINVAL);
 
                io_sync = (ap->a_ioflag & IO_SYNC);
-               io_size = uio->uio_resid;
+               // LP64todo - fix this!
+               io_size = uio_resid(uio);
 
                dev = (vp->v_rdev);
 
@@ -430,91 +471,119 @@ spec_write(ap)
                
 
                do {
-                       bn = (uio->uio_offset / devBlockSize) &~ blkmask;
+                       bn = (daddr64_t)((uio->uio_offset / devBlockSize) &~ blkmask);
                        on = uio->uio_offset % bsize;
 
-                       n = min((unsigned)(bsize - on), uio->uio_resid);
+                       // LP64todo - fix this!
+                       n = min((unsigned)(bsize - on), uio_resid(uio));
+
+                       /*
+                        * Use buf_getblk() as an optimization IFF:
+                        *
+                        * 1)   We are reading exactly a block on a block
+                        *      aligned boundary
+                        * 2)   We know the size of the device from spec_open
+                        * 3)   The read doesn't span the end of the device
+                        *
+                        * Otherwise, we fall back on buf_bread().
+                        */
+                       if (n == bsize &&
+                           vp->v_specdevsize != (u_int64_t)0 &&
+                           (uio->uio_offset + (u_int64_t)n) > vp->v_specdevsize) {
+                           /* reduce the size of the read to what is there */
+                           n = (uio->uio_offset + (u_int64_t)n) - vp->v_specdevsize;
+                       }
 
                        if (n == bsize)
-                               bp = getblk(vp, bn, bsize, 0, 0, BLK_WRITE);
+                               bp = buf_getblk(vp, bn, bsize, 0, 0, BLK_WRITE);
                        else
-                               error = bread(vp, bn, bsize, NOCRED, &bp);
+                               error = (int)buf_bread(vp, bn, bsize, NOCRED, &bp);
 
+                       /* Translate downstream error for upstream, if needed */
+                       if (!error)
+                               error = (int)buf_error(bp);
                        if (error) {
-                               brelse(bp);
+                               buf_brelse(bp);
                                return (error);
                        }
-                       n = min(n, bsize - bp->b_resid);
+                       n = min(n, bsize - buf_resid(bp));
 
-                       error = uiomove((char *)bp->b_data + on, n, uio);
-
-                       bp->b_flags |= B_AGE;
+                       error = uiomove((char *)buf_dataptr(bp) + on, n, uio);
+                       if (error) {
+                               buf_brelse(bp);
+                               return (error);
+                       }
+                       buf_markaged(bp);
 
                        if (io_sync) 
-                               bwrite(bp);
+                               error = buf_bwrite(bp);
                        else {
                                if ((n + on) == bsize)
-                                       bawrite(bp);
+                                       error = buf_bawrite(bp);
                                else
-                                       bdwrite(bp);
+                                       error = buf_bdwrite(bp);
                        }
-               } while (error == 0 && uio->uio_resid > 0 && n != 0);
+               } while (error == 0 && uio_resid(uio) > 0 && n != 0);
                return (error);
 
        default:
                panic("spec_write type");
        }
        /* NOTREACHED */
+
+       return (0);
 }
 
 /*
  * Device ioctl operation.
  */
-/* ARGSUSED */
+int
 spec_ioctl(ap)
-       struct vop_ioctl_args /* {
+       struct vnop_ioctl_args /* {
                struct vnode *a_vp;
                int  a_command;
                caddr_t  a_data;
                int  a_fflag;
-               struct ucred *a_cred;
-               struct proc *a_p;
+               vfs_context_t a_context;
        } */ *ap;
 {
+       proc_t p = vfs_context_proc(ap->a_context);
        dev_t dev = ap->a_vp->v_rdev;
 
        switch (ap->a_vp->v_type) {
 
        case VCHR:
                return ((*cdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data,
-                   ap->a_fflag, ap->a_p));
+                   ap->a_fflag, p));
 
        case VBLK:
-               if (ap->a_command == 0 && (int)ap->a_data == B_TAPE)
+               if (ap->a_command == 0 && (int)ap->a_data == B_TAPE) {
                        if (bdevsw[major(dev)].d_type == D_TAPE)
                                return (0);
                        else
                                return (1);
+               }
                return ((*bdevsw[major(dev)].d_ioctl)(dev, ap->a_command, ap->a_data,
-                  ap->a_fflag, ap->a_p));
+                  ap->a_fflag, p));
 
        default:
                panic("spec_ioctl");
                /* NOTREACHED */
        }
+       return (0);
 }
 
-/* ARGSUSED */
+int
 spec_select(ap)
-       struct vop_select_args /* {
+       struct vnop_select_args /* {
                struct vnode *a_vp;
                int  a_which;
                int  a_fflags;
-               struct ucred *a_cred;
                void * a_wql;
-               struct proc *a_p;
+               vfs_context_t a_context;
        } */ *ap;
 {
+       proc_t p = vfs_context_proc(ap->a_context);
        register dev_t dev;
 
        switch (ap->a_vp->v_type) {
@@ -524,130 +593,154 @@ spec_select(ap)
 
        case VCHR:
                dev = ap->a_vp->v_rdev;
-               return (*cdevsw[major(dev)].d_select)(dev, ap->a_which, ap->a_wql, ap->a_p);
+               return (*cdevsw[major(dev)].d_select)(dev, ap->a_which, ap->a_wql, p);
        }
 }
+
 /*
  * Synch buffers associated with a block device
  */
-/* ARGSUSED */
 int
-spec_fsync(ap)
-       struct vop_fsync_args /* {
-               struct vnode *a_vp;
-               struct ucred *a_cred;
-               int  a_waitfor;
-               struct proc *a_p;
-       } */ *ap;
+spec_fsync_internal(vnode_t vp, int waitfor, __unused vfs_context_t context)
 {
-       register struct vnode *vp = ap->a_vp;
-       register struct buf *bp;
-       struct buf *nbp;
-       int s;
-
        if (vp->v_type == VCHR)
                return (0);
        /*
         * Flush all dirty buffers associated with a block device.
         */
-loop:
-       s = splbio();
-       for (bp = vp->v_dirtyblkhd.lh_first; bp; bp = nbp) {
-               nbp = bp->b_vnbufs.le_next;
-               if ((bp->b_flags & B_BUSY))
-                       continue;
-               if ((bp->b_flags & B_DELWRI) == 0)
-                       panic("spec_fsync: not dirty");
-               bremfree(bp);
-               bp->b_flags |= B_BUSY;
-               splx(s);
-               bawrite(bp);
-               goto loop;
-       }
-       if (ap->a_waitfor == MNT_WAIT) {
-               while (vp->v_numoutput) {
-                       vp->v_flag |= VBWAIT;
-                       tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "spec_fsync", 0);
-               }
-#if DIAGNOSTIC
-               if (vp->v_dirtyblkhd.lh_first) {
-                       vprint("spec_fsync: dirty", vp);
-                       splx(s);
-                       goto loop;
-               }
-#endif
-       }
-       splx(s);
+       buf_flushdirtyblks(vp, waitfor == MNT_WAIT, 0, (char *)"spec_fsync");
+
        return (0);
 }
 
-/*
- * Just call the device strategy routine
- */
-spec_strategy(ap)
-       struct vop_strategy_args /* {
-               struct buf *a_bp;
+int
+spec_fsync(ap)
+       struct vnop_fsync_args /* {
+               struct vnode *a_vp;
+               int  a_waitfor;
+               vfs_context_t a_context;
        } */ *ap;
 {
-       (*bdevsw[major(ap->a_bp->b_dev)].d_strategy)(ap->a_bp);
-       return (0);
+       return spec_fsync_internal(ap->a_vp, ap->a_waitfor, ap->a_context);
 }
 
 /*
- * This is a noop, simply returning what one has been given.
+ * Just call the device strategy routine
  */
-spec_bmap(ap)
-       struct vop_bmap_args /* {
-               struct vnode *a_vp;
-               daddr_t  a_bn;
-               struct vnode **a_vpp;
-               daddr_t *a_bnp;
-               int *a_runp;
+extern int hard_throttle_on_root;
+
+
+#define LOWPRI_DELAY_MSECS     200
+#define LOWPRI_WINDOW_MSECS    200
+
+int    lowpri_IO_window_msecs = LOWPRI_WINDOW_MSECS;
+int    lowpri_IO_delay_msecs  = LOWPRI_DELAY_MSECS;
+
+struct timeval last_normal_IO_timestamp;
+struct timeval last_lowpri_IO_timestamp;
+struct timeval lowpri_IO_window = { 0, LOWPRI_WINDOW_MSECS * 1000 };
+
+int
+spec_strategy(ap)
+       struct vnop_strategy_args /* {
+               struct buf *a_bp;
        } */ *ap;
 {
+        buf_t  bp;
+       int     bflags;
+       dev_t   bdev;
+       proc_t  p;
+        struct timeval elapsed;
+
+        bp = ap->a_bp;
+       bdev = buf_device(bp);
+       bflags = buf_flags(bp);
+
+        if (kdebug_enable) {
+               int    code = 0;
+
+               if (bflags & B_READ)
+                       code |= DKIO_READ;
+               if (bflags & B_ASYNC)
+                       code |= DKIO_ASYNC;
+
+               if (bflags & B_META)
+                       code |= DKIO_META;
+               else if (bflags & B_PAGEIO)
+                       code |= DKIO_PAGING;
+
+               KERNEL_DEBUG_CONSTANT(FSDBG_CODE(DBG_DKRW, code) | DBG_FUNC_NONE,
+                                     (unsigned int)bp, bdev, (int)buf_blkno(bp), buf_count(bp), 0);
+        }
+       if (((bflags & (B_PAGEIO | B_READ)) == (B_PAGEIO | B_READ)) &&
+           (buf_vnode(bp)->v_mount->mnt_kern_flag & MNTK_ROOTDEV))
+               hard_throttle_on_root = 1;
+
+       if ( lowpri_IO_delay_msecs && lowpri_IO_window_msecs ) {
+               p = current_proc();
+
+               if ( (p == NULL) || !(p->p_lflag & P_LLOW_PRI_IO)) {
+                       if (!(p->p_lflag & P_LBACKGROUND_IO))
+                               microuptime(&last_normal_IO_timestamp);
+               } else {
+                       microuptime(&last_lowpri_IO_timestamp);
+
+                       elapsed = last_lowpri_IO_timestamp;
+                       timevalsub(&elapsed, &last_normal_IO_timestamp);
+
+                       lowpri_IO_window.tv_sec  = lowpri_IO_window_msecs / 1000;
+                       lowpri_IO_window.tv_usec = (lowpri_IO_window_msecs % 1000) * 1000;
+
+                       if (timevalcmp(&elapsed, &lowpri_IO_window, <)) {
+                               struct uthread  *ut;
+
+                               /*
+                                * I'd really like to do the IOSleep here, but
+                                * we may be holding all kinds of filesystem related locks
+                                * and the pages for this I/O marked 'busy'...
+                                * we don't want to cause a normal task to block on
+                                * one of these locks while we're throttling a task marked
+                                * for low priority I/O... we'll mark the uthread and
+                                * do the delay just before we return from the system
+                                * call that triggered this I/O or from vnode_pagein
+                                */
+                               ut = get_bsdthread_info(current_thread());
+                               ut->uu_lowpri_delay = lowpri_IO_delay_msecs;
+                       }
+               }
+       }
+        (*bdevsw[major(bdev)].d_strategy)(bp);
 
-       if (ap->a_vpp != NULL)
-               *ap->a_vpp = ap->a_vp;
-       if (ap->a_bnp != NULL)
-               *ap->a_bnp = ap->a_bn * (PAGE_SIZE / ap->a_vp->v_specsize);
-       if (ap->a_runp != NULL)
-               *ap->a_runp = (MAXPHYSIO / PAGE_SIZE) - 1;
-       return (0);
+        return (0);
 }
 
+
 /*
  * This is a noop, simply returning what one has been given.
  */
-spec_cmap(ap)
-       struct vop_cmap_args /* {
-               struct vnode *a_vp;
-               off_t a_offset;    
-               size_t a_size;
-               daddr_t *a_bpn;
-               size_t *a_run;
-               void *a_poff;
-       } */ *ap;
+int
+spec_blockmap(__unused struct vnop_blockmap_args *ap)
 {
-       return (EOPNOTSUPP);
+       return (ENOTSUP);
 }
 
 
 /*
  * Device close routine
  */
-/* ARGSUSED */
+int
 spec_close(ap)
-       struct vop_close_args /* {
+       struct vnop_close_args /* {
                struct vnode *a_vp;
                int  a_fflag;
-               struct ucred *a_cred;
-               struct proc *a_p;
+               vfs_context_t a_context;
        } */ *ap;
 {
        register struct vnode *vp = ap->a_vp;
        dev_t dev = vp->v_rdev;
-       int (*devclose) __P((dev_t, int, int, struct proc *));
+       int (*devclose)(dev_t, int, int, struct proc *);
        int mode, error;
+       struct proc *p = vfs_context_proc(ap->a_context);
 
        switch (vp->v_type) {
 
@@ -661,17 +754,15 @@ spec_close(ap)
                 * if the reference count is 2 (this last descriptor
                 * plus the session), release the reference from the session.
                 */
-               if (vcount(vp) == 2 && ap->a_p &&
-                   vp == ap->a_p->p_session->s_ttyvp) {
-                       ap->a_p->p_session->s_ttyvp = NULL;
-                       vrele(vp);
+               if (vcount(vp) == 2 && p &&
+                   vp == p->p_session->s_ttyvp) {
+                       p->p_session->s_ttyvp = NULL;
+                       vnode_rele(vp);
                }
                /*
-                * If the vnode is locked, then we are in the midst
-                * of forcably closing the device, otherwise we only
                 * close on last reference.
                 */
-               if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
+               if (vcount(vp) > 1)
                        return (0);
                devclose = cdevsw[major(dev)].d_close;
                mode = S_IFCHR;
@@ -684,33 +775,30 @@ spec_close(ap)
                 * we must invalidate any in core blocks, so that
                 * we can, for instance, change floppy disks.
                 */
-               vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, ap->a_p);
-               error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0);
-               VOP_UNLOCK(vp, 0, ap->a_p);
+               if ((error = spec_fsync_internal(vp, MNT_WAIT, ap->a_context)))
+                       return (error);
+
+               error = buf_invalidateblks(vp, BUF_WRITE_DATA, 0, 0);
                if (error)
                        return (error);
                /*
-                * We do not want to really close the device if it
-                * is still in use unless we are trying to close it
-                * forcibly. Since every use (buffer, vnode, swap, cmap)
+                * Since every use (buffer, vnode, swap, blockmap)
                 * holds a reference to the vnode, and because we mark
                 * any other vnodes that alias this device, when the
                 * sum of the reference counts on all the aliased
                 * vnodes descends to one, we are on last close.
                 */
-               if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
+               if (vcount(vp) > 1)
                        return (0);
 #else /* DEVFS_IMPLEMENTS_LOCKING */
                /*
-                * We do not want to really close the device if it
-                * is still in use unless we are trying to close it
-                * forcibly. Since every use (buffer, vnode, swap, cmap)
+                * Since every use (buffer, vnode, swap, blockmap)
                 * holds a reference to the vnode, and because we mark
                 * any other vnodes that alias this device, when the
                 * sum of the reference counts on all the aliased
                 * vnodes descends to one, we are on last close.
                 */
-               if (vcount(vp) > 1 && (vp->v_flag & VXLOCK) == 0)
+               if (vcount(vp) > 1)
                        return (0);
 
                /*
@@ -718,7 +806,10 @@ spec_close(ap)
                 * we must invalidate any in core blocks, so that
                 * we can, for instance, change floppy disks.
                 */
-               error = vinvalbuf(vp, V_SAVE, ap->a_cred, ap->a_p, 0, 0);
+               if ((error = spec_fsync_internal(vp, MNT_WAIT, ap->a_context)))
+                       return (error);
+
+               error = buf_invalidateblks(vp, BUF_WRITE_DATA, 0, 0);
                if (error)
                        return (error);
 #endif /* DEVFS_IMPLEMENTS_LOCKING */
@@ -730,30 +821,19 @@ spec_close(ap)
                panic("spec_close: not special");
        }
 
-       return ((*devclose)(dev, ap->a_fflag, mode, ap->a_p));
-}
-
-/*
- * Print out the contents of a special device vnode.
- */
-spec_print(ap)
-       struct vop_print_args /* {
-               struct vnode *a_vp;
-       } */ *ap;
-{
-
-       printf("tag VT_NON, dev %d, %d\n", major(ap->a_vp->v_rdev),
-               minor(ap->a_vp->v_rdev));
+       return ((*devclose)(dev, ap->a_fflag, mode, p));
 }
 
 /*
  * Return POSIX pathconf information applicable to special devices.
  */
+int
 spec_pathconf(ap)
-       struct vop_pathconf_args /* {
+       struct vnop_pathconf_args /* {
                struct vnode *a_vp;
                int a_name;
                int *a_retval;
+               vfs_context_t a_context;
        } */ *ap;
 {
 
@@ -784,7 +864,7 @@ spec_pathconf(ap)
 
 int
 spec_devblocksize(ap)
-        struct vop_devblocksize_args /* {
+        struct vnop_devblocksize_args /* {
                struct vnode *a_vp;
                int *a_retval;
         } */ *ap;
@@ -796,7 +876,8 @@ spec_devblocksize(ap)
 /*
  * Special device failed operation
  */
-spec_ebadf()
+int
+spec_ebadf(__unused void *dummy)
 {
 
        return (EBADF);
@@ -805,6 +886,7 @@ spec_ebadf()
 /*
  * Special device bad operation
  */
+int
 spec_badop()
 {
 
@@ -815,9 +897,9 @@ spec_badop()
 /* Blktooff derives file offset from logical block number */
 int
 spec_blktooff(ap)
-       struct vop_blktooff_args /* {
+       struct vnop_blktooff_args /* {
                struct vnode *a_vp;
-               daddr_t a_lblkno;
+               daddr64_t a_lblkno;
                off_t *a_offset;    
        } */ *ap;
 {
@@ -826,42 +908,46 @@ spec_blktooff(ap)
        switch (vp->v_type) {
        case VCHR:
                *ap->a_offset = (off_t)-1; /* failure */
-               return (EOPNOTSUPP);
+               return (ENOTSUP);
 
        case VBLK:
                printf("spec_blktooff: not implemented for VBLK\n");
                *ap->a_offset = (off_t)-1; /* failure */
-               return (EOPNOTSUPP);
+               return (ENOTSUP);
 
        default:
                panic("spec_blktooff type");
        }
        /* NOTREACHED */
+
+       return (0);
 }
 
 /* Offtoblk derives logical block number from file offset */
 int
 spec_offtoblk(ap)
-       struct vop_offtoblk_args /* {
+       struct vnop_offtoblk_args /* {
                struct vnode *a_vp;
                off_t a_offset;    
-               daddr_t *a_lblkno;
+               daddr64_t *a_lblkno;
        } */ *ap;
 {
        register struct vnode *vp = ap->a_vp;
 
        switch (vp->v_type) {
        case VCHR:
-               *ap->a_lblkno = (daddr_t)-1; /* failure */
-               return (EOPNOTSUPP);
+               *ap->a_lblkno = (daddr64_t)-1; /* failure */
+               return (ENOTSUP);
 
        case VBLK:
                printf("spec_offtoblk: not implemented for VBLK\n");
-               *ap->a_lblkno = (daddr_t)-1; /* failure */
-               return (EOPNOTSUPP);
+               *ap->a_lblkno = (daddr64_t)-1; /* failure */
+               return (ENOTSUP);
 
        default:
                panic("spec_offtoblk type");
        }
        /* NOTREACHED */
+
+       return (0);
 }