From c9cb5c289d5aaaea9a1cb017bd8b2f24c3483f8e Mon Sep 17 00:00:00 2001 From: phk Date: Wed, 6 Sep 2000 11:26:43 +0000 Subject: Add refcounts to the "global" DEVFS inode slots, this allows us to recycle inodes after a destroy_dev() but not until all mounts have picked up the change. Add support for an overflow table for DEVFS inodes. The static table defaults to 1024 inodes, if that fills, an overflow table of 32k inodes is allocated. Both numbers can be changed at compile time, the size of the overflow table also with the sysctl vfs.devfs.noverflow. Use atomic instructions to barrier between make_dev()/destroy_dev() and the mounts. Add lockmgr() locking of directories for operations accessing or modifying the directory TAILQs. Various nitpicking here and there. --- sys/fs/devfs/devfs_vnops.c | 60 +++++++++++++++++++++++++++++----------------- 1 file changed, 38 insertions(+), 22 deletions(-) (limited to 'sys/fs/devfs/devfs_vnops.c') diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c index e96dafb..db95406 100644 --- a/sys/fs/devfs/devfs_vnops.c +++ b/sys/fs/devfs/devfs_vnops.c @@ -43,19 +43,16 @@ #include #include #include -#include #include #include #include -#include -#define DEVFS_INTERN #include static int devfs_access __P((struct vop_access_args *ap)); static int devfs_badop __P((void)); static int devfs_getattr __P((struct vop_getattr_args *ap)); -static int devfs_lookup __P((struct vop_lookup_args *ap)); +static int devfs_lookupx __P((struct vop_lookup_args *ap)); static int devfs_print __P((struct vop_print_args *ap)); static int devfs_read __P((struct vop_read_args *ap)); static int devfs_readdir __P((struct vop_readdir_args *ap)); @@ -66,12 +63,12 @@ static int devfs_revoke __P((struct vop_revoke_args *ap)); static int devfs_setattr __P((struct vop_setattr_args *ap)); static int devfs_symlink __P((struct vop_symlink_args *ap)); - int devfs_allocv(struct devfs_dirent *de, struct mount *mp, struct vnode **vpp, struct proc *p) { int error; struct vnode *vp; + dev_t dev; if (p == NULL) p = curproc; /* XXX */ @@ -83,6 +80,13 @@ loop: *vpp = vp; return (0); } + if (de->de_dirent->d_type == DT_CHR) { + dev = *devfs_itod(de->de_inode); + if (dev == NULL) + return (ENOENT); + } else { + dev = NODEV; + } error = getnewvnode(VT_DEVFS, mp, devfs_vnodeop_p, &vp); if (error != 0) { printf("devfs_allocv: failed to allocate new vnode\n"); @@ -91,7 +95,7 @@ loop: if (de->de_dirent->d_type == DT_CHR) { vp->v_type = VCHR; - vp = addaliasu(vp, devfs_inot[de->de_inode]->si_udev); + vp = addaliasu(vp, dev->si_udev); vp->v_op = devfs_specop_p; } else if (de->de_dirent->d_type == DT_DIR) { vp->v_type = VDIR; @@ -153,6 +157,7 @@ devfs_getattr(ap) vap->va_mode = de->de_mode; vap->va_size = 0; vap->va_blocksize = DEV_BSIZE; + vap->va_type = vp->v_type; if (vp->v_type != VCHR) { vap->va_atime = de->de_atime; vap->va_mtime = de->de_mtime; @@ -162,23 +167,14 @@ devfs_getattr(ap) vap->va_atime = dev->si_atime; vap->va_mtime = dev->si_mtime; vap->va_ctime = dev->si_ctime; + vap->va_rdev = dev->si_udev; } vap->va_gen = 0; vap->va_flags = 0; - vap->va_rdev = 0; vap->va_bytes = 0; vap->va_nlink = de->de_links; vap->va_fileid = de->de_inode; - if (de->de_dirent->d_type == DT_DIR) { - vap->va_type = VDIR; - } else if (de->de_dirent->d_type == DT_LNK) { - vap->va_type = VLNK; - } else if (de->de_dirent->d_type == DT_CHR) { - vap->va_type = VCHR; - vap->va_rdev = devfs_inot[de->de_inode]->si_udev; - } - #ifdef DEBUG if (error) printf("devfs_getattr: return error %d\n", error); @@ -187,7 +183,7 @@ devfs_getattr(ap) } static int -devfs_lookup(ap) +devfs_lookupx(ap) struct vop_lookup_args /* { struct vnode * a_dvp; struct vnode ** a_vpp; @@ -358,6 +354,19 @@ found: return (0); } +static int +devfs_lookup(struct vop_lookup_args *ap) +{ + int j; + struct devfs_mount *dmp; + + dmp = VFSTODEVFS(ap->a_dvp->v_mount); + lockmgr(&dmp->dm_lock, LK_SHARED, 0, curproc); + j = devfs_lookupx(ap); + lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curproc); + return (j); +} + /* ARGSUSED */ static int devfs_print(ap) @@ -415,6 +424,7 @@ devfs_readdir(ap) return (EINVAL); dmp = VFSTODEVFS(ap->a_vp->v_mount); + lockmgr(&dmp->dm_lock, LK_SHARED, 0, curproc); devfs_populate(dmp); error = 0; de = ap->a_vp->v_data; @@ -437,6 +447,7 @@ devfs_readdir(ap) off += dp->d_reclen; dd = TAILQ_NEXT(dd, de_list); } + lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curproc); uio->uio_offset = off; return (error); } @@ -486,16 +497,19 @@ devfs_remove(ap) { struct vnode *vp = ap->a_vp; struct devfs_dirent *dd; - struct devfs_dirent *de; - struct devfs_mount *dm = VFSTODEVFS(vp->v_mount); + struct devfs_dirent *de, **dep; + struct devfs_mount *dmp = VFSTODEVFS(vp->v_mount); + lockmgr(&dmp->dm_lock, LK_EXCLUSIVE, 0, curproc); dd = ap->a_dvp->v_data; de = vp->v_data; - de->de_flags |= DE_ORPHAN; TAILQ_REMOVE(&dd->de_dlist, de, de_list); - if (de->de_inode < NDEVINO) - dm->dm_dirent[de->de_inode] = DE_DELETED; + dep = devfs_itode(dmp, de->de_inode); + if (dep != NULL) + *dep = DE_DELETED; + de->de_flags |= DE_ORPHAN; vdrop(de->de_vnode); + lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curproc); return (0); } @@ -589,8 +603,10 @@ devfs_symlink(ap) i = strlen(ap->a_target) + 1; MALLOC(de->de_symlink, char *, i, M_DEVFS, M_WAITOK); bcopy(ap->a_target, de->de_symlink, i); + lockmgr(&dmp->dm_lock, LK_EXCLUSIVE, 0, curproc); TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); devfs_allocv(de, ap->a_dvp->v_mount, ap->a_vpp, 0); + lockmgr(&dmp->dm_lock, LK_RELEASE, 0, curproc); return (0); } -- cgit v1.1