/* * (MPSAFE) * * Copyright (c) 2009 The DragonFly Project. All rights reserved. * * This code is derived from software contributed to The DragonFly Project * by Alex Hornung * * 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. Neither the name of The DragonFly Project 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 COPYRIGHT HOLDERS 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 * COPYRIGHT HOLDERS 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef SPEC_CHAIN_DEBUG #define SPEC_CHAIN_DEBUG 0 #endif MALLOC_DECLARE(M_DEVFS); #define DEVFS_BADOP (void *)devfs_vop_badop static int devfs_vop_badop(struct vop_generic_args *); static int devfs_vop_access(struct vop_access_args *); static int devfs_vop_inactive(struct vop_inactive_args *); static int devfs_vop_reclaim(struct vop_reclaim_args *); static int devfs_vop_readdir(struct vop_readdir_args *); static int devfs_vop_getattr(struct vop_getattr_args *); static int devfs_vop_setattr(struct vop_setattr_args *); static int devfs_vop_readlink(struct vop_readlink_args *); static int devfs_vop_print(struct vop_print_args *); static int devfs_vop_nresolve(struct vop_nresolve_args *); static int devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *); static int devfs_vop_nmkdir(struct vop_nmkdir_args *); static int devfs_vop_nsymlink(struct vop_nsymlink_args *); static int devfs_vop_nrmdir(struct vop_nrmdir_args *); static int devfs_vop_nremove(struct vop_nremove_args *); static int devfs_spec_open(struct vop_open_args *); static int devfs_spec_close(struct vop_close_args *); static int devfs_spec_fsync(struct vop_fsync_args *); static int devfs_spec_read(struct vop_read_args *); static int devfs_spec_write(struct vop_write_args *); static int devfs_spec_ioctl(struct vop_ioctl_args *); static int devfs_spec_kqfilter(struct vop_kqfilter_args *); static int devfs_spec_strategy(struct vop_strategy_args *); static void devfs_spec_strategy_done(struct bio *); static int devfs_spec_freeblks(struct vop_freeblks_args *); static int devfs_spec_bmap(struct vop_bmap_args *); static int devfs_spec_advlock(struct vop_advlock_args *); static void devfs_spec_getpages_iodone(struct bio *); static int devfs_spec_getpages(struct vop_getpages_args *); static int devfs_fo_close(struct file *); static int devfs_fo_read(struct file *, struct uio *, struct ucred *, int); static int devfs_fo_write(struct file *, struct uio *, struct ucred *, int); static int devfs_fo_stat(struct file *, struct stat *, struct ucred *); static int devfs_fo_kqfilter(struct file *, struct knote *); static int devfs_fo_ioctl(struct file *, u_long, caddr_t, struct ucred *, struct sysmsg *); static int devfs_fo_seek(struct file *, off_t, int, off_t *); static __inline int sequential_heuristic(struct uio *, struct file *); extern struct lock devfs_lock; /* * devfs vnode operations for regular files. All vnode ops are MPSAFE. */ struct vop_ops devfs_vnode_norm_vops = { .vop_default = vop_defaultop, .vop_access = devfs_vop_access, .vop_advlock = DEVFS_BADOP, .vop_bmap = DEVFS_BADOP, .vop_close = vop_stdclose, .vop_getattr = devfs_vop_getattr, .vop_inactive = devfs_vop_inactive, .vop_ncreate = DEVFS_BADOP, .vop_nresolve = devfs_vop_nresolve, .vop_nlookupdotdot = devfs_vop_nlookupdotdot, .vop_nlink = DEVFS_BADOP, .vop_nmkdir = devfs_vop_nmkdir, .vop_nmknod = DEVFS_BADOP, .vop_nremove = devfs_vop_nremove, .vop_nrename = DEVFS_BADOP, .vop_nrmdir = devfs_vop_nrmdir, .vop_nsymlink = devfs_vop_nsymlink, .vop_open = vop_stdopen, .vop_pathconf = vop_stdpathconf, .vop_print = devfs_vop_print, .vop_read = DEVFS_BADOP, .vop_readdir = devfs_vop_readdir, .vop_readlink = devfs_vop_readlink, .vop_reallocblks = DEVFS_BADOP, .vop_reclaim = devfs_vop_reclaim, .vop_setattr = devfs_vop_setattr, .vop_write = DEVFS_BADOP, .vop_ioctl = DEVFS_BADOP }; /* * devfs vnode operations for character devices. All vnode ops are MPSAFE. */ struct vop_ops devfs_vnode_dev_vops = { .vop_default = vop_defaultop, .vop_access = devfs_vop_access, .vop_advlock = devfs_spec_advlock, .vop_bmap = devfs_spec_bmap, .vop_close = devfs_spec_close, .vop_freeblks = devfs_spec_freeblks, .vop_fsync = devfs_spec_fsync, .vop_getattr = devfs_vop_getattr, .vop_getpages = devfs_spec_getpages, .vop_inactive = devfs_vop_inactive, .vop_open = devfs_spec_open, .vop_pathconf = vop_stdpathconf, .vop_print = devfs_vop_print, .vop_kqfilter = devfs_spec_kqfilter, .vop_read = devfs_spec_read, .vop_readdir = DEVFS_BADOP, .vop_readlink = DEVFS_BADOP, .vop_reallocblks = DEVFS_BADOP, .vop_reclaim = devfs_vop_reclaim, .vop_setattr = devfs_vop_setattr, .vop_strategy = devfs_spec_strategy, .vop_write = devfs_spec_write, .vop_ioctl = devfs_spec_ioctl }; /* * devfs file pointer operations. All fileops are MPSAFE. */ struct vop_ops *devfs_vnode_dev_vops_p = &devfs_vnode_dev_vops; struct fileops devfs_dev_fileops = { .fo_read = devfs_fo_read, .fo_write = devfs_fo_write, .fo_ioctl = devfs_fo_ioctl, .fo_kqfilter = devfs_fo_kqfilter, .fo_stat = devfs_fo_stat, .fo_close = devfs_fo_close, .fo_shutdown = nofo_shutdown, .fo_seek = devfs_fo_seek }; /* * These two functions are possibly temporary hacks for devices (aka * the pty code) which want to control the node attributes themselves. * * XXX we may ultimately desire to simply remove the uid/gid/mode * from the node entirely. * * MPSAFE - sorta. Theoretically the overwrite can compete since they * are loading from the same fields. */ static __inline void node_sync_dev_get(struct devfs_node *node) { cdev_t dev; if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) { node->uid = dev->si_uid; node->gid = dev->si_gid; node->mode = dev->si_perms; } } static __inline void node_sync_dev_set(struct devfs_node *node) { cdev_t dev; if ((dev = node->d_dev) && (dev->si_flags & SI_OVERRIDE)) { dev->si_uid = node->uid; dev->si_gid = node->gid; dev->si_perms = node->mode; } } /* * generic entry point for unsupported operations */ static int devfs_vop_badop(struct vop_generic_args *ap) { return (EIO); } static int devfs_vop_access(struct vop_access_args *ap) { struct devfs_node *node = DEVFS_NODE(ap->a_vp); int error; if (!devfs_node_is_accessible(node)) return ENOENT; node_sync_dev_get(node); error = vop_helper_access(ap, node->uid, node->gid, node->mode, node->flags); return error; } static int devfs_vop_inactive(struct vop_inactive_args *ap) { struct devfs_node *node = DEVFS_NODE(ap->a_vp); if (node == NULL || (node->flags & DEVFS_NODE_LINKED) == 0) vrecycle(ap->a_vp); return 0; } static int devfs_vop_reclaim(struct vop_reclaim_args *ap) { struct devfs_node *node; struct vnode *vp; int locked; /* * Check if it is locked already. if not, we acquire the devfs lock */ if ((lockstatus(&devfs_lock, curthread)) != LK_EXCLUSIVE) { lockmgr(&devfs_lock, LK_EXCLUSIVE); locked = 1; } else { locked = 0; } /* * Get rid of the devfs_node if it is no longer linked into the * topology. Interlocked by devfs_lock. However, be careful * interposing other operations between cleaning out v_data and * devfs_freep() as the node is only protected by devfs_lock * once the vnode is disassociated. */ vp = ap->a_vp; node = DEVFS_NODE(vp); if (node) { if (node->v_node != vp) { kprintf("NODE->V_NODE MISMATCH VP=%p NODEVP=%p\n", vp, node->v_node); } vp->v_data = NULL; node->v_node = NULL; if ((node->flags & DEVFS_NODE_LINKED) == 0) devfs_freep(node); } v_release_rdev(vp); if (locked) lockmgr(&devfs_lock, LK_RELEASE); /* * v_rdev needs to be properly released using v_release_rdev * Make sure v_data is NULL as well. */ return 0; } static int devfs_vop_readdir(struct vop_readdir_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_vp); struct devfs_node *node; int cookie_index; int ncookies; int error2; int error; int r; off_t *cookies; off_t saveoff; devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_readdir() called!\n"); if (ap->a_uio->uio_offset < 0 || ap->a_uio->uio_offset > INT_MAX) return (EINVAL); error = vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY | LK_FAILRECLAIM); if (error) return (error); if (!devfs_node_is_accessible(dnode)) { vn_unlock(ap->a_vp); return ENOENT; } lockmgr(&devfs_lock, LK_EXCLUSIVE); saveoff = ap->a_uio->uio_offset; if (ap->a_ncookies) { ncookies = ap->a_uio->uio_resid / 16 + 1; /* Why / 16 ?? */ if (ncookies > 256) ncookies = 256; cookies = kmalloc(256 * sizeof(off_t), M_TEMP, M_WAITOK); cookie_index = 0; } else { ncookies = -1; cookies = NULL; cookie_index = 0; } vfs_timestamp(&dnode->atime); if (saveoff == 0) { r = vop_write_dirent(&error, ap->a_uio, dnode->d_dir.d_ino, DT_DIR, 1, "."); if (r) goto done; if (cookies) cookies[cookie_index] = saveoff; saveoff++; cookie_index++; if (cookie_index == ncookies) goto done; } if (saveoff == 1) { if (dnode->parent) { r = vop_write_dirent(&error, ap->a_uio, dnode->parent->d_dir.d_ino, DT_DIR, 2, ".."); } else { r = vop_write_dirent(&error, ap->a_uio, dnode->d_dir.d_ino, DT_DIR, 2, ".."); } if (r) goto done; if (cookies) cookies[cookie_index] = saveoff; saveoff++; cookie_index++; if (cookie_index == ncookies) goto done; } TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { if ((node->flags & DEVFS_HIDDEN) || (node->flags & DEVFS_INVISIBLE)) { continue; } /* * If the node type is a valid devfs alias, then we make * sure that the target isn't hidden. If it is, we don't * show the link in the directory listing. */ if ((node->node_type == Nlink) && (node->link_target != NULL) && (node->link_target->flags & DEVFS_HIDDEN)) continue; if (node->cookie < saveoff) continue; saveoff = node->cookie; error2 = vop_write_dirent(&error, ap->a_uio, node->d_dir.d_ino, node->d_dir.d_type, node->d_dir.d_namlen, node->d_dir.d_name); if (error2) break; saveoff++; if (cookies) cookies[cookie_index] = node->cookie; ++cookie_index; if (cookie_index == ncookies) break; } done: lockmgr(&devfs_lock, LK_RELEASE); vn_unlock(ap->a_vp); ap->a_uio->uio_offset = saveoff; if (error && cookie_index == 0) { if (cookies) { kfree(cookies, M_TEMP); *ap->a_ncookies = 0; *ap->a_cookies = NULL; } } else { if (cookies) { *ap->a_ncookies = cookie_index; *ap->a_cookies = cookies; } } return (error); } static int devfs_vop_nresolve(struct vop_nresolve_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); struct devfs_node *node, *found = NULL; struct namecache *ncp; struct vnode *vp = NULL; int error = 0; int len; int depth; ncp = ap->a_nch->ncp; len = ncp->nc_nlen; if (!devfs_node_is_accessible(dnode)) return ENOENT; lockmgr(&devfs_lock, LK_EXCLUSIVE); if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) { error = ENOENT; cache_setvp(ap->a_nch, NULL); goto out; } TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { if (len == node->d_dir.d_namlen) { if (!memcmp(ncp->nc_name, node->d_dir.d_name, len)) { found = node; break; } } } if (found) { depth = 0; while ((found->node_type == Nlink) && (found->link_target)) { if (depth >= 8) { devfs_debug(DEVFS_DEBUG_SHOW, "Recursive link or depth >= 8"); break; } found = found->link_target; ++depth; } if (!(found->flags & DEVFS_HIDDEN)) devfs_allocv(/*ap->a_dvp->v_mount, */ &vp, found); } if (vp == NULL) { error = ENOENT; cache_setvp(ap->a_nch, NULL); goto out; } KKASSERT(vp); vn_unlock(vp); cache_setvp(ap->a_nch, vp); vrele(vp); out: lockmgr(&devfs_lock, LK_RELEASE); return error; } static int devfs_vop_nlookupdotdot(struct vop_nlookupdotdot_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); *ap->a_vpp = NULL; if (!devfs_node_is_accessible(dnode)) return ENOENT; lockmgr(&devfs_lock, LK_EXCLUSIVE); if (dnode->parent != NULL) { devfs_allocv(ap->a_vpp, dnode->parent); vn_unlock(*ap->a_vpp); } lockmgr(&devfs_lock, LK_RELEASE); return ((*ap->a_vpp == NULL) ? ENOENT : 0); } /* * getattr() - Does not need a lock since the vp is refd */ static int devfs_vop_getattr(struct vop_getattr_args *ap) { struct devfs_node *node = DEVFS_NODE(ap->a_vp); struct vattr *vap = ap->a_vap; struct partinfo pinfo; int error = 0; #if 0 if (!devfs_node_is_accessible(node)) return ENOENT; #endif /* * XXX This is a temporary hack to prevent crashes when the device is * being destroyed (and so the underlying node will be gone) while * a userland program is blocked in a read(). */ if (node == NULL) return EIO; node_sync_dev_get(node); /* start by zeroing out the attributes */ VATTR_NULL(vap); /* next do all the common fields */ vap->va_type = ap->a_vp->v_type; vap->va_mode = node->mode; vap->va_fileid = DEVFS_NODE(ap->a_vp)->d_dir.d_ino ; vap->va_flags = 0; vap->va_blocksize = DEV_BSIZE; vap->va_bytes = vap->va_size = 0; vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; vap->va_atime = node->atime; vap->va_mtime = node->mtime; vap->va_ctime = node->ctime; vap->va_nlink = 1; /* number of references to file */ vap->va_uid = node->uid; vap->va_gid = node->gid; vap->va_rmajor = 0; vap->va_rminor = 0; if ((node->node_type == Ndev) && node->d_dev) { reference_dev(node->d_dev); vap->va_rminor = node->d_dev->si_uminor; release_dev(node->d_dev); } /* For a softlink the va_size is the length of the softlink */ if (node->symlink_name != 0) { vap->va_bytes = vap->va_size = node->symlink_namelen; } /* * For a disk-type device, va_size is the size of the underlying * device, so that lseek() works properly. */ if ((node->d_dev) && (dev_dflags(node->d_dev) & D_DISK)) { bzero(&pinfo, sizeof(pinfo)); error = dev_dioctl(node->d_dev, DIOCGPART, (void *)&pinfo, 0, proc0.p_ucred, NULL, NULL); if ((error == 0) && (pinfo.media_blksize != 0)) { vap->va_size = pinfo.media_size; } else { vap->va_size = 0; error = 0; } } return (error); } static int devfs_vop_setattr(struct vop_setattr_args *ap) { struct devfs_node *node = DEVFS_NODE(ap->a_vp); struct vattr *vap; uid_t cur_uid; gid_t cur_gid; mode_t cur_mode; int error = 0; if (!devfs_node_is_accessible(node)) return ENOENT; node_sync_dev_get(node); vap = ap->a_vap; if ((vap->va_uid != (uid_t)VNOVAL) || (vap->va_gid != (gid_t)VNOVAL)) { cur_uid = node->uid; cur_gid = node->gid; cur_mode = node->mode; error = vop_helper_chown(ap->a_vp, vap->va_uid, vap->va_gid, ap->a_cred, &cur_uid, &cur_gid, &cur_mode); if (error) goto out; if (node->uid != cur_uid || node->gid != cur_gid) { node->uid = cur_uid; node->gid = cur_gid; node->mode = cur_mode; } } if (vap->va_mode != (mode_t)VNOVAL) { cur_mode = node->mode; error = vop_helper_chmod(ap->a_vp, vap->va_mode, ap->a_cred, node->uid, node->gid, &cur_mode); if (error == 0 && node->mode != cur_mode) { node->mode = cur_mode; } } out: node_sync_dev_set(node); vfs_timestamp(&node->ctime); return error; } static int devfs_vop_readlink(struct vop_readlink_args *ap) { struct devfs_node *node = DEVFS_NODE(ap->a_vp); int ret; if (!devfs_node_is_accessible(node)) return ENOENT; lockmgr(&devfs_lock, LK_SHARED); ret = uiomove(node->symlink_name, node->symlink_namelen, ap->a_uio); lockmgr(&devfs_lock, LK_RELEASE); return ret; } static int devfs_vop_print(struct vop_print_args *ap) { return (0); } static int devfs_vop_nmkdir(struct vop_nmkdir_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); struct devfs_node *node; if (!devfs_node_is_accessible(dnode)) return ENOENT; if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) goto out; lockmgr(&devfs_lock, LK_EXCLUSIVE); devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Ndir, ap->a_nch->ncp->nc_name, dnode, NULL); if (*ap->a_vpp) { node = DEVFS_NODE(*ap->a_vpp); node->flags |= DEVFS_USER_CREATED; cache_setunresolved(ap->a_nch); cache_setvp(ap->a_nch, *ap->a_vpp); } lockmgr(&devfs_lock, LK_RELEASE); out: return ((*ap->a_vpp == NULL) ? ENOTDIR : 0); } static int devfs_vop_nsymlink(struct vop_nsymlink_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); struct devfs_node *node; size_t targetlen; if (!devfs_node_is_accessible(dnode)) return ENOENT; ap->a_vap->va_type = VLNK; if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) goto out; lockmgr(&devfs_lock, LK_EXCLUSIVE); devfs_allocvp(ap->a_dvp->v_mount, ap->a_vpp, Nlink, ap->a_nch->ncp->nc_name, dnode, NULL); targetlen = strlen(ap->a_target); if (*ap->a_vpp) { node = DEVFS_NODE(*ap->a_vpp); node->flags |= DEVFS_USER_CREATED; node->symlink_namelen = targetlen; node->symlink_name = kmalloc(targetlen + 1, M_DEVFS, M_WAITOK); memcpy(node->symlink_name, ap->a_target, targetlen); node->symlink_name[targetlen] = '\0'; cache_setunresolved(ap->a_nch); cache_setvp(ap->a_nch, *ap->a_vpp); } lockmgr(&devfs_lock, LK_RELEASE); out: return ((*ap->a_vpp == NULL) ? ENOTDIR : 0); } static int devfs_vop_nrmdir(struct vop_nrmdir_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); struct devfs_node *node; struct namecache *ncp; int error = ENOENT; ncp = ap->a_nch->ncp; if (!devfs_node_is_accessible(dnode)) return ENOENT; lockmgr(&devfs_lock, LK_EXCLUSIVE); if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) goto out; TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { if (ncp->nc_nlen != node->d_dir.d_namlen) continue; if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen)) continue; /* * only allow removal of user created dirs */ if ((node->flags & DEVFS_USER_CREATED) == 0) { error = EPERM; goto out; } else if (node->node_type != Ndir) { error = ENOTDIR; goto out; } else if (node->nchildren > 2) { error = ENOTEMPTY; goto out; } else { if (node->v_node) cache_inval_vp(node->v_node, CINV_DESTROY); devfs_unlinkp(node); error = 0; break; } } cache_unlink(ap->a_nch); out: lockmgr(&devfs_lock, LK_RELEASE); return error; } static int devfs_vop_nremove(struct vop_nremove_args *ap) { struct devfs_node *dnode = DEVFS_NODE(ap->a_dvp); struct devfs_node *node; struct namecache *ncp; int error = ENOENT; ncp = ap->a_nch->ncp; if (!devfs_node_is_accessible(dnode)) return ENOENT; lockmgr(&devfs_lock, LK_EXCLUSIVE); if ((dnode->node_type != Nroot) && (dnode->node_type != Ndir)) goto out; TAILQ_FOREACH(node, DEVFS_DENODE_HEAD(dnode), link) { if (ncp->nc_nlen != node->d_dir.d_namlen) continue; if (memcmp(ncp->nc_name, node->d_dir.d_name, ncp->nc_nlen)) continue; /* * only allow removal of user created stuff (e.g. symlinks) */ if ((node->flags & DEVFS_USER_CREATED) == 0) { error = EPERM; goto out; } else if (node->node_type == Ndir) { error = EISDIR; goto out; } else { if (node->v_node) cache_inval_vp(node->v_node, CINV_DESTROY); devfs_unlinkp(node); error = 0; break; } } cache_unlink(ap->a_nch); out: lockmgr(&devfs_lock, LK_RELEASE); return error; } static int devfs_spec_open(struct vop_open_args *ap) { struct vnode *vp = ap->a_vp; struct vnode *orig_vp = NULL; struct devfs_node *node = DEVFS_NODE(vp); struct devfs_node *newnode; cdev_t dev, ndev = NULL; int error = 0; if (node) { if (node->d_dev == NULL) return ENXIO; if (!devfs_node_is_accessible(node)) return ENOENT; } if ((dev = vp->v_rdev) == NULL) return ENXIO; /* * Simple devices that don't care. Retain the shared lock. */ if (dev_dflags(dev) & D_QUICK) { vn_unlock(vp); error = dev_dopen(dev, ap->a_mode, S_IFCHR, ap->a_cred, ap->a_fpp, vp); vn_lock(vp, LK_SHARED | LK_RETRY); if (error) return error; vop_stdopen(ap); goto skip; } /* * Slow code */ vn_lock(vp, LK_UPGRADE | LK_RETRY); if (node && ap->a_fpp) { int exists; devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_open: -1.1-\n"); lockmgr(&devfs_lock, LK_SHARED); ndev = devfs_clone(dev, node->d_dir.d_name, node->d_dir.d_namlen, ap->a_mode, ap->a_cred); if (ndev != NULL) { lockmgr(&devfs_lock, LK_RELEASE); lockmgr(&devfs_lock, LK_EXCLUSIVE); newnode = devfs_create_device_node( DEVFS_MNTDATA(vp->v_mount)->root_node, ndev, &exists, NULL, NULL); /* XXX: possibly destroy device if this happens */ if (newnode != NULL) { dev = ndev; if (exists == 0) devfs_link_dev(dev); devfs_debug(DEVFS_DEBUG_DEBUG, "parent here is: %s, node is: |%s|\n", ((node->parent->node_type == Nroot) ? "ROOT!" : node->parent->d_dir.d_name), newnode->d_dir.d_name); devfs_debug(DEVFS_DEBUG_DEBUG, "test: %s\n", ((struct devfs_node *)(TAILQ_LAST(DEVFS_DENODE_HEAD(node->parent), devfs_node_head)))->d_dir.d_name); /* * orig_vp is set to the original vp if we * cloned. */ /* node->flags |= DEVFS_CLONED; */ devfs_allocv(&vp, newnode); orig_vp = ap->a_vp; ap->a_vp = vp; } } lockmgr(&devfs_lock, LK_RELEASE); /* * Synchronize devfs here to make sure that, if the cloned * device creates other device nodes in addition to the * cloned one, all of them are created by the time we return * from opening the cloned one. */ if (ndev) devfs_config(); } devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_open() called on %s! \n", dev->si_name); /* * Make this field valid before any I/O in ->d_open * * NOTE: Shared vnode lock probably held, but its ok as long * as assignments are consistent. */ if (!dev->si_iosize_max) /* XXX: old DFLTPHYS == 64KB dependency */ dev->si_iosize_max = min(MAXPHYS,64*1024); if (dev_dflags(dev) & D_TTY) vsetflags(vp, VISTTY); /* * Open the underlying device. * * NOTE: If the dev open returns EALREADY it has completed the open * operation and is returning a fully initialized *a->a_fpp * (which it may also have replaced). This includes issuing * any necessary VOP_OPEN(). * * Also, the returned ap->a_fpp might not be DTYPE_VNODE and * if it is might not be using the vp we supplied to it. */ vn_unlock(vp); error = dev_dopen(dev, ap->a_mode, S_IFCHR, ap->a_cred, ap->a_fpp, vp); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); if (__predict_false(error == EALREADY)) { if (orig_vp) vput(vp); return 0; } /* * Clean up any cloned vp if we error out. */ if (__predict_false(error != 0)) { if (orig_vp) { vput(vp); ap->a_vp = orig_vp; /* orig_vp = NULL; */ } return error; } /* * This checks if the disk device is going to be opened for writing. * It will be only allowed in the cases where securelevel permits it * and it's not mounted R/W. */ if ((dev_dflags(dev) & D_DISK) && (ap->a_mode & FWRITE) && (ap->a_cred != FSCRED)) { /* Very secure mode. No open for writing allowed */ if (securelevel >= 2) return EPERM; /* * If it is mounted R/W, do not allow to open for writing. * In the case it's mounted read-only but securelevel * is >= 1, then do not allow opening for writing either. */ if (vfs_mountedon(vp)) { if (!(dev->si_mountpoint->mnt_flag & MNT_RDONLY)) return EBUSY; else if (securelevel >= 1) return EPERM; } } /* * NOTE: vnode is still locked shared. t_stop assignment should * remain consistent so we should be ok. */ if (dev_dflags(dev) & D_TTY) { if (dev->si_tty) { struct tty *tp; tp = dev->si_tty; if (!tp->t_stop) { devfs_debug(DEVFS_DEBUG_DEBUG, "devfs: no t_stop\n"); tp->t_stop = nottystop; } } } /* * NOTE: vnode is still locked shared. assignments should * remain consistent so we should be ok. However, * upgrade to exclusive if we need a VM object. */ if (vn_isdisk(vp, NULL)) { if (!dev->si_bsize_phys) dev->si_bsize_phys = DEV_BSIZE; vinitvmio(vp, IDX_TO_OFF(INT_MAX), PAGE_SIZE, -1); } vop_stdopen(ap); #if 0 if (node) vfs_timestamp(&node->atime); #endif /* * If we replaced the vp the vop_stdopen() call will have loaded * it into fp->f_data and vref()d the vp, giving us two refs. So * instead of just unlocking it here we have to vput() it. */ if (orig_vp) vput(vp); /* Ugly pty magic, to make pty devices appear once they are opened */ if (node && (node->flags & DEVFS_PTY) == DEVFS_PTY) { if (node->flags & DEVFS_INVISIBLE) node->flags &= ~DEVFS_INVISIBLE; } skip: if (ap->a_fpp) { struct file *fp = *ap->a_fpp; KKASSERT(fp->f_type == DTYPE_VNODE); KKASSERT((fp->f_flag & FMASK) == (ap->a_mode & FMASK)); fp->f_ops = &devfs_dev_fileops; KKASSERT(fp->f_data == (void *)vp); } return 0; } static int devfs_spec_close(struct vop_close_args *ap) { struct devfs_node *node; struct proc *p = curproc; struct vnode *vp = ap->a_vp; cdev_t dev = vp->v_rdev; int error = 0; int needrelock; int opencount; /* * Devices flagged D_QUICK require no special handling. */ if (dev && dev_dflags(dev) & D_QUICK) { opencount = vp->v_opencount; if (opencount <= 1) opencount = count_dev(dev); /* XXX NOT SMP SAFE */ if (((vp->v_flag & VRECLAIMED) || (dev_dflags(dev) & D_TRACKCLOSE) || (opencount == 1))) { vn_unlock(vp); error = dev_dclose(dev, ap->a_fflag, S_IFCHR, ap->a_fp); vn_lock(vp, LK_SHARED | LK_RETRY); } goto skip; } /* * We do special tests on the opencount so unfortunately we need * an exclusive lock. */ vn_lock(vp, LK_UPGRADE | LK_RETRY); if (dev) devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() called on %s! \n", dev->si_name); else devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() called, null vode!\n"); /* * A couple of hacks for devices and tty devices. The * vnode ref count cannot be used to figure out the * last close, but we can use v_opencount now that * revoke works properly. * * Detect the last close on a controlling terminal and clear * the session (half-close). * * XXX opencount is not SMP safe. The vnode is locked but there * may be multiple vnodes referencing the same device. */ if (dev) { /* * NOTE: Try to avoid global tokens when testing opencount * XXX hack, fixme. needs a struct lock and opencount in * struct cdev itself. */ reference_dev(dev); opencount = vp->v_opencount; if (opencount <= 1) opencount = count_dev(dev); /* XXX NOT SMP SAFE */ } else { opencount = 0; } if (p && vp->v_opencount <= 1 && vp == p->p_session->s_ttyvp) { p->p_session->s_ttyvp = NULL; vrele(vp); } /* * Vnodes can be opened and closed multiple times. Do not really * close the device unless (1) it is being closed forcibly, * (2) the device wants to track closes, or (3) this is the last * vnode doing its last close on the device. * * XXX the VXLOCK (force close) case can leave vnodes referencing * a closed device. This might not occur now that our revoke is * fixed. */ devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -1- \n"); if (dev && ((vp->v_flag & VRECLAIMED) || (dev_dflags(dev) & D_TRACKCLOSE) || (opencount == 1))) { /* * Ugly pty magic, to make pty devices disappear again once * they are closed. */ node = DEVFS_NODE(ap->a_vp); if (node && (node->flags & DEVFS_PTY)) node->flags |= DEVFS_INVISIBLE; /* * Unlock around dev_dclose(), unless the vnode is * undergoing a vgone/reclaim (during umount). */ needrelock = 0; if ((vp->v_flag & VRECLAIMED) == 0 && vn_islocked(vp)) { needrelock = 1; vn_unlock(vp); } /* * WARNING! If the device destroys itself the devfs node * can disappear here. * * WARNING! vn_lock() will fail if the vp is in a VRECLAIM, * which can occur during umount. */ error = dev_dclose(dev, ap->a_fflag, S_IFCHR, ap->a_fp); /* node is now stale */ if (needrelock) { if (vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_FAILRECLAIM) != 0) { panic("devfs_spec_close: vnode %p " "unexpectedly could not be relocked", vp); } } } else { error = 0; } devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_spec_close() -2- \n"); /* * Track the actual opens and closes on the vnode. The last close * disassociates the rdev. If the rdev is already disassociated or * the opencount is already 0, the vnode might have been revoked * and no further opencount tracking occurs. */ if (dev) release_dev(dev); skip: if (vp->v_opencount > 0) vop_stdclose(ap); return(error); } static int devfs_fo_close(struct file *fp) { struct vnode *vp = (struct vnode *)fp->f_data; int error; fp->f_ops = &badfileops; error = vn_close(vp, fp->f_flag, fp); devfs_clear_cdevpriv(fp); return (error); } /* * Device-optimized file table vnode read routine. * * This bypasses the VOP table and talks directly to the device. Most * filesystems just route to specfs and can make this optimization. */ static int devfs_fo_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags) { struct devfs_node *node; struct vnode *vp; int ioflag; int error; cdev_t dev; KASSERT(uio->uio_td == curthread, ("uio_td %p is not td %p", uio->uio_td, curthread)); if (uio->uio_resid == 0) return 0; vp = (struct vnode *)fp->f_data; if (vp == NULL || vp->v_type == VBAD) return EBADF; node = DEVFS_NODE(vp); if ((dev = vp->v_rdev) == NULL) return EBADF; reference_dev(dev); if ((flags & O_FOFFSET) == 0) uio->uio_offset = fp->f_offset; ioflag = 0; if (flags & O_FBLOCKING) { /* ioflag &= ~IO_NDELAY; */ } else if (flags & O_FNONBLOCKING) { ioflag |= IO_NDELAY; } else if (fp->f_flag & FNONBLOCK) { ioflag |= IO_NDELAY; } if (fp->f_flag & O_DIRECT) { ioflag |= IO_DIRECT; } ioflag |= sequential_heuristic(uio, fp); error = dev_dread(dev, uio, ioflag, fp); release_dev(dev); if (node) vfs_timestamp(&node->atime); if ((flags & O_FOFFSET) == 0) fp->f_offset = uio->uio_offset; fp->f_nextoff = uio->uio_offset; return (error); } static int devfs_fo_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags) { struct devfs_node *node; struct vnode *vp; int ioflag; int error; cdev_t dev; KASSERT(uio->uio_td == curthread, ("uio_td %p is not p %p", uio->uio_td, curthread)); vp = (struct vnode *)fp->f_data; if (vp == NULL || vp->v_type == VBAD) return EBADF; node = DEVFS_NODE(vp); if (vp->v_type == VREG) bwillwrite(uio->uio_resid); vp = (struct vnode *)fp->f_data; if ((dev = vp->v_rdev) == NULL) return EBADF; reference_dev(dev); if ((flags & O_FOFFSET) == 0) uio->uio_offset = fp->f_offset; ioflag = IO_UNIT; if (vp->v_type == VREG && ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { ioflag |= IO_APPEND; } if (flags & O_FBLOCKING) { /* ioflag &= ~IO_NDELAY; */ } else if (flags & O_FNONBLOCKING) { ioflag |= IO_NDELAY; } else if (fp->f_flag & FNONBLOCK) { ioflag |= IO_NDELAY; } if (fp->f_flag & O_DIRECT) { ioflag |= IO_DIRECT; } if (flags & O_FASYNCWRITE) { /* ioflag &= ~IO_SYNC; */ } else if (flags & O_FSYNCWRITE) { ioflag |= IO_SYNC; } else if (fp->f_flag & O_FSYNC) { ioflag |= IO_SYNC; } if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) ioflag |= IO_SYNC; ioflag |= sequential_heuristic(uio, fp); error = dev_dwrite(dev, uio, ioflag, fp); release_dev(dev); if (node) { vfs_timestamp(&node->atime); vfs_timestamp(&node->mtime); } if ((flags & O_FOFFSET) == 0) fp->f_offset = uio->uio_offset; fp->f_nextoff = uio->uio_offset; return (error); } static int devfs_fo_stat(struct file *fp, struct stat *sb, struct ucred *cred) { struct vnode *vp; struct vattr vattr; struct vattr *vap; u_short mode; cdev_t dev; int error; vp = (struct vnode *)fp->f_data; if (vp == NULL || vp->v_type == VBAD) return EBADF; error = vn_stat(vp, sb, cred); if (error) return (error); vap = &vattr; error = VOP_GETATTR(vp, vap); if (error) return (error); /* * Zero the spare stat fields */ sb->st_lspare = 0; sb->st_qspare2 = 0; /* * Copy from vattr table ... or not in case it's a cloned device */ if (vap->va_fsid != VNOVAL) sb->st_dev = vap->va_fsid; else sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; sb->st_ino = vap->va_fileid; mode = vap->va_mode; mode |= S_IFCHR; sb->st_mode = mode; if (vap->va_nlink > (nlink_t)-1) sb->st_nlink = (nlink_t)-1; else sb->st_nlink = vap->va_nlink; sb->st_uid = vap->va_uid; sb->st_gid = vap->va_gid; sb->st_rdev = devid_from_dev(DEVFS_NODE(vp)->d_dev); sb->st_size = vap->va_bytes; sb->st_atimespec = vap->va_atime; sb->st_mtimespec = vap->va_mtime; sb->st_ctimespec = vap->va_ctime; /* * A VCHR and VBLK device may track the last access and last modified * time independantly of the filesystem. This is particularly true * because device read and write calls may bypass the filesystem. */ if (vp->v_type == VCHR || vp->v_type == VBLK) { dev = vp->v_rdev; if (dev != NULL) { if (dev->si_lastread) { sb->st_atimespec.tv_sec = time_second + (dev->si_lastread - time_uptime); sb->st_atimespec.tv_nsec = 0; } if (dev->si_lastwrite) { sb->st_mtimespec.tv_sec = time_second + (dev->si_lastwrite - time_uptime); sb->st_mtimespec.tv_nsec = 0; } } } /* * According to www.opengroup.org, the meaning of st_blksize is * "a filesystem-specific preferred I/O block size for this * object. In some filesystem types, this may vary from file * to file" * Default to PAGE_SIZE after much discussion. */ sb->st_blksize = PAGE_SIZE; sb->st_flags = vap->va_flags; error = caps_priv_check(cred, SYSCAP_NOVFS_GENERATION); if (error) sb->st_gen = 0; else sb->st_gen = (u_int32_t)vap->va_gen; sb->st_blocks = vap->va_bytes / S_BLKSIZE; /* * This is for ABI compatibility <= 5.7 (for ABI change made in * 5.7 master). */ sb->__old_st_blksize = sb->st_blksize; return (0); } static int devfs_fo_kqfilter(struct file *fp, struct knote *kn) { struct vnode *vp; int error; cdev_t dev; vp = (struct vnode *)fp->f_data; if (vp == NULL || vp->v_type == VBAD) { error = EBADF; goto done; } if ((dev = vp->v_rdev) == NULL) { error = EBADF; goto done; } reference_dev(dev); error = dev_dkqfilter(dev, kn, fp); release_dev(dev); done: return (error); } static int devfs_fo_ioctl(struct file *fp, u_long com, caddr_t data, struct ucred *ucred, struct sysmsg *msg) { #if 0 struct devfs_node *node; #endif struct vnode *vp; struct vnode *ovp; cdev_t dev; int error; struct fiodname_args *name_args; size_t namlen; const char *name; vp = ((struct vnode *)fp->f_data); if ((dev = vp->v_rdev) == NULL) return EBADF; /* device was revoked */ reference_dev(dev); #if 0 node = DEVFS_NODE(vp); #endif devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl() called! for dev %s\n", dev->si_name); if (com == FIODTYPE) { *(int *)data = dev_dflags(dev) & D_TYPEMASK; error = 0; goto out; } else if (com == FIODNAME) { name_args = (struct fiodname_args *)data; name = dev->si_name; namlen = strlen(name) + 1; devfs_debug(DEVFS_DEBUG_DEBUG, "ioctl, got: FIODNAME for %s\n", name); if (namlen <= name_args->len) error = copyout(dev->si_name, name_args->name, namlen); else error = EINVAL; devfs_debug(DEVFS_DEBUG_DEBUG, "ioctl stuff: error: %d\n", error); goto out; } error = dev_dioctl(dev, com, data, fp->f_flag, ucred, msg, fp); #if 0 if (node) { vfs_timestamp(&node->atime); vfs_timestamp(&node->mtime); } #endif if (com == TIOCSCTTY) { devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl: got TIOCSCTTY on %s\n", dev->si_name); } if (error == 0 && com == TIOCSCTTY) { struct proc *p = curthread->td_proc; struct session *sess; devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl: dealing with TIOCSCTTY on %s\n", dev->si_name); if (p == NULL) { error = ENOTTY; goto out; } sess = p->p_session; /* * Do nothing if reassigning same control tty */ if (sess->s_ttyvp == vp) { error = 0; goto out; } /* * Get rid of reference to old control tty */ ovp = sess->s_ttyvp; vref(vp); sess->s_ttyvp = vp; if (ovp) vrele(ovp); } out: release_dev(dev); devfs_debug(DEVFS_DEBUG_DEBUG, "devfs_fo_ioctl() finished! \n"); return (error); } int devfs_fo_seek(struct file *fp, off_t offset, int whence, off_t *res) { /* * NOTE: vnode_fileops uses exact same code */ struct vnode *vp; struct vattr_lite lva; off_t new_offset; int error; vp = (struct vnode *)fp->f_data; switch (whence) { case L_INCR: spin_lock(&fp->f_spin); new_offset = fp->f_offset + offset; error = 0; break; case L_XTND: error = VOP_GETATTR_LITE(vp, &lva); spin_lock(&fp->f_spin); new_offset = offset + lva.va_size; break; case L_SET: new_offset = offset; error = 0; spin_lock(&fp->f_spin); break; default: new_offset = 0; error = EINVAL; spin_lock(&fp->f_spin); break; } /* * Validate the seek position. Negative offsets are not allowed * for regular files or directories. * * Normally we would also not want to allow negative offsets for * character and block-special devices. However kvm addresses * on 64 bit architectures might appear to be negative and must * be allowed. */ if (error == 0) { if (new_offset < 0 && (vp->v_type == VREG || vp->v_type == VDIR)) { error = EINVAL; } else { fp->f_offset = new_offset; } } *res = fp->f_offset; spin_unlock(&fp->f_spin); return (error); } static int devfs_spec_fsync(struct vop_fsync_args *ap) { struct vnode *vp = ap->a_vp; int error; if (!vn_isdisk(vp, NULL)) return (0); /* * Flush all dirty buffers associated with a block device. */ error = vfsync(vp, ap->a_waitfor, 10000, NULL, NULL); return (error); } static int devfs_spec_read(struct vop_read_args *ap) { struct devfs_node *node; struct vnode *vp; struct uio *uio; cdev_t dev; int error; vp = ap->a_vp; dev = vp->v_rdev; uio = ap->a_uio; node = DEVFS_NODE(vp); if (dev == NULL) /* device was revoked */ return (EBADF); if (uio->uio_resid == 0) return (0); vn_unlock(vp); error = dev_dread(dev, uio, ap->a_ioflag, NULL); vn_lock(vp, LK_SHARED | LK_RETRY); if (node) vfs_timestamp(&node->atime); return (error); } /* * Vnode op for write * * spec_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag, * struct ucred *a_cred) */ static int devfs_spec_write(struct vop_write_args *ap) { struct devfs_node *node; struct vnode *vp; struct uio *uio; cdev_t dev; int error; vp = ap->a_vp; dev = vp->v_rdev; uio = ap->a_uio; node = DEVFS_NODE(vp); KKASSERT(uio->uio_segflg != UIO_NOCOPY); if (dev == NULL) /* device was revoked */ return (EBADF); vn_unlock(vp); error = dev_dwrite(dev, uio, ap->a_ioflag, NULL); vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); if (node) { vfs_timestamp(&node->atime); vfs_timestamp(&node->mtime); } return (error); } /* * Device ioctl operation. * * spec_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data, * int a_fflag, struct ucred *a_cred, struct sysmsg *msg) */ static int devfs_spec_ioctl(struct vop_ioctl_args *ap) { struct vnode *vp = ap->a_vp; #if 0 struct devfs_node *node; #endif cdev_t dev; if ((dev = vp->v_rdev) == NULL) return (EBADF); /* device was revoked */ #if 0 node = DEVFS_NODE(vp); if (node) { vfs_timestamp(&node->atime); vfs_timestamp(&node->mtime); } #endif return (dev_dioctl(dev, ap->a_command, ap->a_data, ap->a_fflag, ap->a_cred, ap->a_sysmsg, NULL)); } /* * spec_kqfilter(struct vnode *a_vp, struct knote *a_kn) */ /* ARGSUSED */ static int devfs_spec_kqfilter(struct vop_kqfilter_args *ap) { struct vnode *vp = ap->a_vp; #if 0 struct devfs_node *node; #endif cdev_t dev; if ((dev = vp->v_rdev) == NULL) return (EBADF); /* device was revoked (EBADF) */ #if 0 node = DEVFS_NODE(vp); if (node) vfs_timestamp(&node->atime); #endif return (dev_dkqfilter(dev, ap->a_kn, NULL)); } /* * Convert a vnode strategy call into a device strategy call. Vnode strategy * calls are not limited to device DMA limits so we have to deal with the * case. * * spec_strategy(struct vnode *a_vp, struct bio *a_bio) */ static int devfs_spec_strategy(struct vop_strategy_args *ap) { struct bio *bio = ap->a_bio; struct buf *bp = bio->bio_buf; struct buf *nbp; struct vnode *vp; struct mount *mp; int chunksize; int maxiosize; if (bp->b_cmd != BUF_CMD_READ && LIST_FIRST(&bp->b_dep) != NULL) buf_start(bp); /* * Collect statistics on synchronous and asynchronous read * and write counts for disks that have associated filesystems. */ vp = ap->a_vp; KKASSERT(vp->v_rdev != NULL); /* XXX */ if (vn_isdisk(vp, NULL) && (mp = vp->v_rdev->si_mountpoint) != NULL) { if (bp->b_cmd == BUF_CMD_READ) { if (bp->b_flags & BIO_SYNC) mp->mnt_stat.f_syncreads++; else mp->mnt_stat.f_asyncreads++; } else { if (bp->b_flags & BIO_SYNC) mp->mnt_stat.f_syncwrites++; else mp->mnt_stat.f_asyncwrites++; } } /* * Device iosize limitations only apply to read and write. Shortcut * the I/O if it fits. */ if ((maxiosize = vp->v_rdev->si_iosize_max) == 0) { devfs_debug(DEVFS_DEBUG_DEBUG, "%s: si_iosize_max not set!\n", dev_dname(vp->v_rdev)); maxiosize = MAXPHYS; } #if SPEC_CHAIN_DEBUG & 2 maxiosize = 4096; #endif if (bp->b_bcount <= maxiosize || (bp->b_cmd != BUF_CMD_READ && bp->b_cmd != BUF_CMD_WRITE)) { dev_dstrategy_chain(vp->v_rdev, bio); return (0); } /* * Clone the buffer and set up an I/O chain to chunk up the I/O. */ nbp = kmalloc(sizeof(*bp), M_DEVBUF, M_INTWAIT|M_ZERO); initbufbio(nbp); buf_dep_init(nbp); BUF_LOCK(nbp, LK_EXCLUSIVE); BUF_KERNPROC(nbp); nbp->b_vp = vp; nbp->b_flags = B_PAGING | B_KVABIO | (bp->b_flags & B_BNOCLIP); nbp->b_cpumask = bp->b_cpumask; nbp->b_data = bp->b_data; nbp->b_bio1.bio_done = devfs_spec_strategy_done; nbp->b_bio1.bio_offset = bio->bio_offset; nbp->b_bio1.bio_caller_info1.ptr = bio; /* * Start the first transfer */ if (vn_isdisk(vp, NULL)) chunksize = vp->v_rdev->si_bsize_phys; else chunksize = DEV_BSIZE; chunksize = rounddown(maxiosize, chunksize); #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy chained I/O chunksize=%d\n", chunksize); #endif nbp->b_cmd = bp->b_cmd; nbp->b_bcount = chunksize; nbp->b_bufsize = chunksize; /* used to detect a short I/O */ nbp->b_bio1.bio_caller_info2.index = chunksize; #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p offset %d/%d bcount %d\n", bp, 0, bp->b_bcount, nbp->b_bcount); #endif dev_dstrategy(vp->v_rdev, &nbp->b_bio1); if (DEVFS_NODE(vp)) { vfs_timestamp(&DEVFS_NODE(vp)->atime); vfs_timestamp(&DEVFS_NODE(vp)->mtime); } return (0); } /* * Chunked up transfer completion routine - chain transfers until done * * NOTE: MPSAFE callback. */ static void devfs_spec_strategy_done(struct bio *nbio) { struct buf *nbp = nbio->bio_buf; struct bio *bio = nbio->bio_caller_info1.ptr; /* original bio */ struct buf *bp = bio->bio_buf; /* original bp */ int chunksize = nbio->bio_caller_info2.index; /* chunking */ int boffset = nbp->b_data - bp->b_data; if (nbp->b_flags & B_ERROR) { /* * An error terminates the chain, propogate the error back * to the original bp */ bp->b_flags |= B_ERROR; bp->b_error = nbp->b_error; bp->b_resid = bp->b_bcount - boffset + (nbp->b_bcount - nbp->b_resid); #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p error %d bcount %d/%d\n", bp, bp->b_error, bp->b_bcount, bp->b_bcount - bp->b_resid); #endif } else if (nbp->b_resid) { /* * A short read or write terminates the chain */ bp->b_error = nbp->b_error; bp->b_resid = bp->b_bcount - boffset + (nbp->b_bcount - nbp->b_resid); #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p short read(1) " "bcount %d/%d\n", bp, bp->b_bcount - bp->b_resid, bp->b_bcount); #endif } else if (nbp->b_bcount != nbp->b_bufsize) { /* * A short read or write can also occur by truncating b_bcount */ #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p short read(2) " "bcount %d/%d\n", bp, nbp->b_bcount + boffset, bp->b_bcount); #endif bp->b_error = 0; bp->b_bcount = nbp->b_bcount + boffset; bp->b_resid = nbp->b_resid; } else if (nbp->b_bcount + boffset == bp->b_bcount) { /* * No more data terminates the chain */ #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p finished bcount %d\n", bp, bp->b_bcount); #endif bp->b_error = 0; bp->b_resid = 0; } else { /* * Continue the chain */ boffset += nbp->b_bcount; nbp->b_data = bp->b_data + boffset; nbp->b_bcount = bp->b_bcount - boffset; if (nbp->b_bcount > chunksize) nbp->b_bcount = chunksize; nbp->b_bio1.bio_done = devfs_spec_strategy_done; nbp->b_bio1.bio_offset = bio->bio_offset + boffset; #if SPEC_CHAIN_DEBUG & 1 devfs_debug(DEVFS_DEBUG_DEBUG, "spec_strategy: chain %p offset %d/%d bcount %d\n", bp, boffset, bp->b_bcount, nbp->b_bcount); #endif dev_dstrategy(nbp->b_vp->v_rdev, &nbp->b_bio1); return; } /* * Fall through to here on termination. biodone(bp) and * clean up and free nbp. */ biodone(bio); BUF_UNLOCK(nbp); uninitbufbio(nbp); kfree(nbp, M_DEVBUF); } /* * spec_freeblks(struct vnode *a_vp, daddr_t a_addr, daddr_t a_length) */ static int devfs_spec_freeblks(struct vop_freeblks_args *ap) { struct buf *bp; /* * Must be a synchronous operation */ KKASSERT(ap->a_vp->v_rdev != NULL); if ((ap->a_vp->v_rdev->si_flags & SI_CANFREE) == 0) return (0); bp = getpbuf(NULL); bp->b_cmd = BUF_CMD_FREEBLKS; bp->b_bio1.bio_flags |= BIO_SYNC; bp->b_bio1.bio_offset = ap->a_offset; bp->b_bio1.bio_done = biodone_sync; bp->b_bcount = ap->a_length; dev_dstrategy(ap->a_vp->v_rdev, &bp->b_bio1); biowait(&bp->b_bio1, "TRIM"); relpbuf(bp, NULL); return (0); } /* * Implement degenerate case where the block requested is the block * returned, and assume that the entire device is contiguous in regards * to the contiguous block range (runp and runb). * * spec_bmap(struct vnode *a_vp, off_t a_loffset, * off_t *a_doffsetp, int *a_runp, int *a_runb) */ static int devfs_spec_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 = MAXBSIZE; if (ap->a_runb != NULL) { if (ap->a_loffset < MAXBSIZE) *ap->a_runb = (int)ap->a_loffset; else *ap->a_runb = MAXBSIZE; } return (0); } /* * Special device advisory byte-level locks. * * spec_advlock(struct vnode *a_vp, caddr_t a_id, int a_op, * struct flock *a_fl, int a_flags) */ /* ARGSUSED */ static int devfs_spec_advlock(struct vop_advlock_args *ap) { return ((ap->a_flags & F_POSIX) ? EINVAL : EOPNOTSUPP); } /* * NOTE: MPSAFE callback. */ static void devfs_spec_getpages_iodone(struct bio *bio) { bio->bio_buf->b_cmd = BUF_CMD_DONE; wakeup(bio->bio_buf); } /* * spec_getpages() - get pages associated with device vnode. * * Note that spec_read and spec_write do not use the buffer cache, so we * must fully implement getpages here. */ static int devfs_spec_getpages(struct vop_getpages_args *ap) { vm_offset_t kva; int error; int i, pcount, size; struct buf *bp; vm_page_t m; vm_ooffset_t offset; int toff, nextoff, nread; struct vnode *vp = ap->a_vp; int blksiz; int gotreqpage; error = 0; pcount = round_page(ap->a_count) / PAGE_SIZE; /* * Calculate the offset of the transfer and do sanity check. */ offset = IDX_TO_OFF(ap->a_m[0]->pindex) + ap->a_offset; /* * Round up physical size for real devices. We cannot round using * v_mount's block size data because v_mount has nothing to do with * the device. i.e. it's usually '/dev'. We need the physical block * size for the device itself. * * We can't use v_rdev->si_mountpoint because it only exists when the * block device is mounted. However, we can use v_rdev. */ if (vn_isdisk(vp, NULL)) blksiz = vp->v_rdev->si_bsize_phys; else blksiz = DEV_BSIZE; size = roundup2(ap->a_count, blksiz); bp = getpbuf_kva(NULL); kva = (vm_offset_t)bp->b_data; /* * Map the pages to be read into the kva. */ pmap_qenter_noinval(kva, ap->a_m, pcount); /* Build a minimal buffer header. */ bp->b_cmd = BUF_CMD_READ; bp->b_flags |= B_KVABIO; bp->b_bcount = size; bp->b_resid = 0; bsetrunningbufspace(bp, size); bp->b_bio1.bio_offset = offset; bp->b_bio1.bio_done = devfs_spec_getpages_iodone; mycpu->gd_cnt.v_vnodein++; mycpu->gd_cnt.v_vnodepgsin += pcount; /* Do the input. */ vn_strategy(ap->a_vp, &bp->b_bio1); crit_enter(); /* We definitely need to be at splbio here. */ while (bp->b_cmd != BUF_CMD_DONE) tsleep(bp, 0, "spread", 0); crit_exit(); if (bp->b_flags & B_ERROR) { if (bp->b_error) error = bp->b_error; else error = EIO; } /* * If EOF is encountered we must zero-extend the result in order * to ensure that the page does not contain garabge. When no * error occurs, an early EOF is indicated if b_bcount got truncated. * b_resid is relative to b_bcount and should be 0, but some devices * might indicate an EOF with b_resid instead of truncating b_bcount. */ nread = bp->b_bcount - bp->b_resid; if (nread < ap->a_count) { bkvasync(bp); bzero((caddr_t)kva + nread, ap->a_count - nread); } pmap_qremove_noinval(kva, pcount); gotreqpage = 0; for (i = 0, toff = 0; i < pcount; i++, toff = nextoff) { nextoff = toff + PAGE_SIZE; m = ap->a_m[i]; /* * NOTE: vm_page_undirty/clear_dirty etc do not clear the * pmap modified bit. pmap modified bit should have * already been cleared. */ if (nextoff <= nread) { m->valid = VM_PAGE_BITS_ALL; vm_page_undirty(m); } else if (toff < nread) { /* * Since this is a VM request, we have to supply the * unaligned offset to allow vm_page_set_valid() * to zero sub-DEV_BSIZE'd portions of the page. */ vm_page_set_valid(m, 0, nread - toff); vm_page_clear_dirty_end_nonincl(m, 0, nread - toff); } else { m->valid = 0; vm_page_undirty(m); } if (i != ap->a_reqpage) { /* * Just in case someone was asking for this page we * now tell them that it is ok to use. */ if (!error || (m->valid == VM_PAGE_BITS_ALL)) { if (m->valid) { if (m->flags & PG_REFERENCED) { vm_page_activate(m); } else { vm_page_deactivate(m); } vm_page_wakeup(m); } else { vm_page_free(m); } } else { vm_page_free(m); } } else if (m->valid) { gotreqpage = 1; /* * Since this is a VM request, we need to make the * entire page presentable by zeroing invalid sections. */ if (m->valid != VM_PAGE_BITS_ALL) vm_page_zero_invalid(m, FALSE); } } if (!gotreqpage) { m = ap->a_m[ap->a_reqpage]; devfs_debug(DEVFS_DEBUG_WARNING, "spec_getpages:(%s) I/O read failure: (error=%d) bp %p vp %p\n", devtoname(vp->v_rdev), error, bp, bp->b_vp); devfs_debug(DEVFS_DEBUG_WARNING, " size: %d, resid: %d, a_count: %d, valid: 0x%x\n", size, bp->b_resid, ap->a_count, m->valid); devfs_debug(DEVFS_DEBUG_WARNING, " nread: %d, reqpage: %d, pindex: %lu, pcount: %d\n", nread, ap->a_reqpage, (u_long)m->pindex, pcount); /* * Free the buffer header back to the swap buffer pool. */ relpbuf(bp, NULL); return VM_PAGER_ERROR; } /* * Free the buffer header back to the swap buffer pool. */ relpbuf(bp, NULL); if (DEVFS_NODE(ap->a_vp)) vfs_timestamp(&DEVFS_NODE(ap->a_vp)->mtime); return VM_PAGER_OK; } static __inline int sequential_heuristic(struct uio *uio, struct file *fp) { /* * Sequential heuristic - detect sequential operation */ if ((uio->uio_offset == 0 && fp->f_seqcount > 0) || uio->uio_offset == fp->f_nextoff) { /* * XXX we assume that the filesystem block size is * the default. Not true, but still gives us a pretty * good indicator of how sequential the read operations * are. */ int tmpseq = fp->f_seqcount; tmpseq += howmany(uio->uio_resid, MAXBSIZE); if (tmpseq > IO_SEQMAX) tmpseq = IO_SEQMAX; fp->f_seqcount = tmpseq; return(fp->f_seqcount << IO_SEQSHIFT); } /* * Not sequential, quick draw-down of seqcount */ if (fp->f_seqcount > 1) fp->f_seqcount = 1; else fp->f_seqcount = 0; return(0); }