Current Path : /sys/amd64/compile/hs32/modules/usr/src/sys/modules/sound/driver/envy24/@/fs/devfs/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //sys/amd64/compile/hs32/modules/usr/src/sys/modules/sound/driver/envy24/@/fs/devfs/devfs_devs.c |
/*- * Copyright (c) 2000,2004 * Poul-Henning Kamp. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36 * * $FreeBSD: release/9.1.0/sys/fs/devfs/devfs_devs.c 226577 2011-10-20 18:47:58Z kib $ */ #include <sys/param.h> #include <sys/systm.h> #include <sys/conf.h> #include <sys/dirent.h> #include <sys/kernel.h> #include <sys/limits.h> #include <sys/lock.h> #include <sys/malloc.h> #include <sys/proc.h> #include <sys/sx.h> #include <sys/sysctl.h> #include <sys/vnode.h> #include <sys/kdb.h> #include <fs/devfs/devfs.h> #include <fs/devfs/devfs_int.h> #include <security/mac/mac_framework.h> /* * The one true (but secret) list of active devices in the system. * Locked by dev_lock()/devmtx */ struct cdev_priv_list cdevp_list = TAILQ_HEAD_INITIALIZER(cdevp_list); struct unrhdr *devfs_inos; static MALLOC_DEFINE(M_DEVFS2, "DEVFS2", "DEVFS data 2"); static MALLOC_DEFINE(M_DEVFS3, "DEVFS3", "DEVFS data 3"); static MALLOC_DEFINE(M_CDEVP, "DEVFS1", "DEVFS cdev_priv storage"); static SYSCTL_NODE(_vfs, OID_AUTO, devfs, CTLFLAG_RW, 0, "DEVFS filesystem"); static unsigned devfs_generation; SYSCTL_UINT(_vfs_devfs, OID_AUTO, generation, CTLFLAG_RD, &devfs_generation, 0, "DEVFS generation number"); unsigned devfs_rule_depth = 1; SYSCTL_UINT(_vfs_devfs, OID_AUTO, rule_depth, CTLFLAG_RW, &devfs_rule_depth, 0, "Max depth of ruleset include"); /* * Helper sysctl for devname(3). We're given a dev_t and return the * name, if any, registered by the device driver. */ static int sysctl_devname(SYSCTL_HANDLER_ARGS) { int error; dev_t ud; struct cdev_priv *cdp; struct cdev *dev; error = SYSCTL_IN(req, &ud, sizeof (ud)); if (error) return (error); if (ud == NODEV) return (EINVAL); dev = NULL; dev_lock(); TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) if (cdp->cdp_inode == ud) { dev = &cdp->cdp_c; dev_refl(dev); break; } dev_unlock(); if (dev == NULL) return (ENOENT); error = SYSCTL_OUT(req, dev->si_name, strlen(dev->si_name) + 1); dev_rel(dev); return (error); } SYSCTL_PROC(_kern, OID_AUTO, devname, CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_ANYBODY|CTLFLAG_MPSAFE, NULL, 0, sysctl_devname, "", "devname(3) handler"); SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev, CTLFLAG_RD, 0, sizeof(struct cdev), "sizeof(struct cdev)"); SYSCTL_INT(_debug_sizeof, OID_AUTO, cdev_priv, CTLFLAG_RD, 0, sizeof(struct cdev_priv), "sizeof(struct cdev_priv)"); struct cdev * devfs_alloc(int flags) { struct cdev_priv *cdp; struct cdev *cdev; struct timespec ts; cdp = malloc(sizeof *cdp, M_CDEVP, M_USE_RESERVE | M_ZERO | ((flags & MAKEDEV_NOWAIT) ? M_NOWAIT : M_WAITOK)); if (cdp == NULL) return (NULL); cdp->cdp_dirents = &cdp->cdp_dirent0; cdp->cdp_dirent0 = NULL; cdp->cdp_maxdirent = 0; cdp->cdp_inode = 0; cdev = &cdp->cdp_c; cdev->si_name = cdev->__si_namebuf; LIST_INIT(&cdev->si_children); vfs_timestamp(&ts); cdev->si_atime = cdev->si_mtime = cdev->si_ctime = ts; cdev->si_cred = NULL; return (cdev); } int devfs_dev_exists(const char *name) { struct cdev_priv *cdp; mtx_assert(&devmtx, MA_OWNED); TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { if ((cdp->cdp_flags & CDP_ACTIVE) == 0) continue; if (devfs_pathpath(cdp->cdp_c.si_name, name) != 0) return (1); if (devfs_pathpath(name, cdp->cdp_c.si_name) != 0) return (1); } if (devfs_dir_find(name) != 0) return (1); return (0); } void devfs_free(struct cdev *cdev) { struct cdev_priv *cdp; cdp = cdev2priv(cdev); if (cdev->si_cred != NULL) crfree(cdev->si_cred); devfs_free_cdp_inode(cdp->cdp_inode); if (cdp->cdp_maxdirent > 0) free(cdp->cdp_dirents, M_DEVFS2); free(cdp, M_CDEVP); } struct devfs_dirent * devfs_find(struct devfs_dirent *dd, const char *name, int namelen, int type) { struct devfs_dirent *de; TAILQ_FOREACH(de, &dd->de_dlist, de_list) { if (namelen != de->de_dirent->d_namlen) continue; if (type != 0 && type != de->de_dirent->d_type) continue; if (bcmp(name, de->de_dirent->d_name, namelen) != 0) continue; break; } KASSERT(de == NULL || (de->de_flags & DE_DOOMED) == 0, ("devfs_find: returning a doomed entry")); return (de); } struct devfs_dirent * devfs_newdirent(char *name, int namelen) { int i; struct devfs_dirent *de; struct dirent d; d.d_namlen = namelen; i = sizeof (*de) + GENERIC_DIRSIZ(&d); de = malloc(i, M_DEVFS3, M_WAITOK | M_ZERO); de->de_dirent = (struct dirent *)(de + 1); de->de_dirent->d_namlen = namelen; de->de_dirent->d_reclen = GENERIC_DIRSIZ(&d); bcopy(name, de->de_dirent->d_name, namelen); de->de_dirent->d_name[namelen] = '\0'; vfs_timestamp(&de->de_ctime); de->de_mtime = de->de_atime = de->de_ctime; de->de_links = 1; de->de_holdcnt = 1; #ifdef MAC mac_devfs_init(de); #endif return (de); } struct devfs_dirent * devfs_parent_dirent(struct devfs_dirent *de) { if (de->de_dirent->d_type != DT_DIR) return (de->de_dir); if (de->de_flags & (DE_DOT | DE_DOTDOT)) return (NULL); de = TAILQ_FIRST(&de->de_dlist); /* "." */ if (de == NULL) return (NULL); de = TAILQ_NEXT(de, de_list); /* ".." */ if (de == NULL) return (NULL); return (de->de_dir); } struct devfs_dirent * devfs_vmkdir(struct devfs_mount *dmp, char *name, int namelen, struct devfs_dirent *dotdot, u_int inode) { struct devfs_dirent *dd; struct devfs_dirent *de; /* Create the new directory */ dd = devfs_newdirent(name, namelen); TAILQ_INIT(&dd->de_dlist); dd->de_dirent->d_type = DT_DIR; dd->de_mode = 0555; dd->de_links = 2; dd->de_dir = dd; if (inode != 0) dd->de_inode = inode; else dd->de_inode = alloc_unr(devfs_inos); /* * "." and ".." are always the two first entries in the * de_dlist list. * * Create the "." entry in the new directory. */ de = devfs_newdirent(".", 1); de->de_dirent->d_type = DT_DIR; de->de_flags |= DE_DOT; TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); de->de_dir = dd; /* Create the ".." entry in the new directory. */ de = devfs_newdirent("..", 2); de->de_dirent->d_type = DT_DIR; de->de_flags |= DE_DOTDOT; TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); if (dotdot == NULL) { de->de_dir = dd; } else { de->de_dir = dotdot; sx_assert(&dmp->dm_lock, SX_XLOCKED); TAILQ_INSERT_TAIL(&dotdot->de_dlist, dd, de_list); dotdot->de_links++; devfs_rules_apply(dmp, dd); } #ifdef MAC mac_devfs_create_directory(dmp->dm_mount, name, namelen, dd); #endif return (dd); } void devfs_dirent_free(struct devfs_dirent *de) { free(de, M_DEVFS3); } /* * Removes a directory if it is empty. Also empty parent directories are * removed recursively. */ static void devfs_rmdir_empty(struct devfs_mount *dm, struct devfs_dirent *de) { struct devfs_dirent *dd, *de_dot, *de_dotdot; sx_assert(&dm->dm_lock, SX_XLOCKED); for (;;) { KASSERT(de->de_dirent->d_type == DT_DIR, ("devfs_rmdir_empty: de is not a directory")); if ((de->de_flags & DE_DOOMED) != 0 || de == dm->dm_rootdir) return; de_dot = TAILQ_FIRST(&de->de_dlist); KASSERT(de_dot != NULL, ("devfs_rmdir_empty: . missing")); de_dotdot = TAILQ_NEXT(de_dot, de_list); KASSERT(de_dotdot != NULL, ("devfs_rmdir_empty: .. missing")); /* Return if the directory is not empty. */ if (TAILQ_NEXT(de_dotdot, de_list) != NULL) return; dd = devfs_parent_dirent(de); KASSERT(dd != NULL, ("devfs_rmdir_empty: NULL dd")); TAILQ_REMOVE(&de->de_dlist, de_dot, de_list); TAILQ_REMOVE(&de->de_dlist, de_dotdot, de_list); TAILQ_REMOVE(&dd->de_dlist, de, de_list); DEVFS_DE_HOLD(dd); devfs_delete(dm, de, DEVFS_DEL_NORECURSE); devfs_delete(dm, de_dot, DEVFS_DEL_NORECURSE); devfs_delete(dm, de_dotdot, DEVFS_DEL_NORECURSE); if (DEVFS_DE_DROP(dd)) { devfs_dirent_free(dd); return; } de = dd; } } /* * The caller needs to hold the dm for the duration of the call since * dm->dm_lock may be temporary dropped. */ void devfs_delete(struct devfs_mount *dm, struct devfs_dirent *de, int flags) { struct devfs_dirent *dd; struct vnode *vp; KASSERT((de->de_flags & DE_DOOMED) == 0, ("devfs_delete doomed dirent")); de->de_flags |= DE_DOOMED; if ((flags & DEVFS_DEL_NORECURSE) == 0) { dd = devfs_parent_dirent(de); if (dd != NULL) DEVFS_DE_HOLD(dd); if (de->de_flags & DE_USER) { KASSERT(dd != NULL, ("devfs_delete: NULL dd")); devfs_dir_unref_de(dm, dd); } } else dd = NULL; mtx_lock(&devfs_de_interlock); vp = de->de_vnode; if (vp != NULL) { VI_LOCK(vp); mtx_unlock(&devfs_de_interlock); vholdl(vp); sx_unlock(&dm->dm_lock); if ((flags & DEVFS_DEL_VNLOCKED) == 0) vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); else VI_UNLOCK(vp); vgone(vp); if ((flags & DEVFS_DEL_VNLOCKED) == 0) VOP_UNLOCK(vp, 0); vdrop(vp); sx_xlock(&dm->dm_lock); } else mtx_unlock(&devfs_de_interlock); if (de->de_symlink) { free(de->de_symlink, M_DEVFS); de->de_symlink = NULL; } #ifdef MAC mac_devfs_destroy(de); #endif if (de->de_inode > DEVFS_ROOTINO) { devfs_free_cdp_inode(de->de_inode); de->de_inode = 0; } if (DEVFS_DE_DROP(de)) devfs_dirent_free(de); if (dd != NULL) { if (DEVFS_DE_DROP(dd)) devfs_dirent_free(dd); else devfs_rmdir_empty(dm, dd); } } /* * Called on unmount. * Recursively removes the entire tree. * The caller needs to hold the dm for the duration of the call. */ static void devfs_purge(struct devfs_mount *dm, struct devfs_dirent *dd) { struct devfs_dirent *de; sx_assert(&dm->dm_lock, SX_XLOCKED); DEVFS_DE_HOLD(dd); for (;;) { /* * Use TAILQ_LAST() to remove "." and ".." last. * We might need ".." to resolve a path in * devfs_dir_unref_de(). */ de = TAILQ_LAST(&dd->de_dlist, devfs_dlist_head); if (de == NULL) break; TAILQ_REMOVE(&dd->de_dlist, de, de_list); if (de->de_flags & DE_USER) devfs_dir_unref_de(dm, dd); if (de->de_flags & (DE_DOT | DE_DOTDOT)) devfs_delete(dm, de, DEVFS_DEL_NORECURSE); else if (de->de_dirent->d_type == DT_DIR) devfs_purge(dm, de); else devfs_delete(dm, de, DEVFS_DEL_NORECURSE); } if (DEVFS_DE_DROP(dd)) devfs_dirent_free(dd); else if ((dd->de_flags & DE_DOOMED) == 0) devfs_delete(dm, dd, DEVFS_DEL_NORECURSE); } /* * Each cdev_priv has an array of pointers to devfs_dirent which is indexed * by the mount points dm_idx. * This function extends the array when necessary, taking into account that * the default array is 1 element and not malloc'ed. */ static void devfs_metoo(struct cdev_priv *cdp, struct devfs_mount *dm) { struct devfs_dirent **dep; int siz; siz = (dm->dm_idx + 1) * sizeof *dep; dep = malloc(siz, M_DEVFS2, M_WAITOK | M_ZERO); dev_lock(); if (dm->dm_idx <= cdp->cdp_maxdirent) { /* We got raced */ dev_unlock(); free(dep, M_DEVFS2); return; } memcpy(dep, cdp->cdp_dirents, (cdp->cdp_maxdirent + 1) * sizeof *dep); if (cdp->cdp_maxdirent > 0) free(cdp->cdp_dirents, M_DEVFS2); cdp->cdp_dirents = dep; /* * XXX: if malloc told us how much we actually got this could * XXX: be optimized. */ cdp->cdp_maxdirent = dm->dm_idx; dev_unlock(); } /* * The caller needs to hold the dm for the duration of the call. */ static int devfs_populate_loop(struct devfs_mount *dm, int cleanup) { struct cdev_priv *cdp; struct devfs_dirent *de; struct devfs_dirent *dd; struct cdev *pdev; int de_flags, j; char *q, *s; sx_assert(&dm->dm_lock, SX_XLOCKED); dev_lock(); TAILQ_FOREACH(cdp, &cdevp_list, cdp_list) { KASSERT(cdp->cdp_dirents != NULL, ("NULL cdp_dirents")); /* * If we are unmounting, or the device has been destroyed, * clean up our dirent. */ if ((cleanup || !(cdp->cdp_flags & CDP_ACTIVE)) && dm->dm_idx <= cdp->cdp_maxdirent && cdp->cdp_dirents[dm->dm_idx] != NULL) { de = cdp->cdp_dirents[dm->dm_idx]; cdp->cdp_dirents[dm->dm_idx] = NULL; KASSERT(cdp == de->de_cdp, ("%s %d %s %p %p", __func__, __LINE__, cdp->cdp_c.si_name, cdp, de->de_cdp)); KASSERT(de->de_dir != NULL, ("Null de->de_dir")); dev_unlock(); TAILQ_REMOVE(&de->de_dir->de_dlist, de, de_list); de->de_cdp = NULL; de->de_inode = 0; devfs_delete(dm, de, 0); dev_lock(); cdp->cdp_inuse--; dev_unlock(); return (1); } /* * GC any lingering devices */ if (!(cdp->cdp_flags & CDP_ACTIVE)) { if (cdp->cdp_inuse > 0) continue; TAILQ_REMOVE(&cdevp_list, cdp, cdp_list); dev_unlock(); dev_rel(&cdp->cdp_c); return (1); } /* * Don't create any new dirents if we are unmounting */ if (cleanup) continue; KASSERT((cdp->cdp_flags & CDP_ACTIVE), ("Bogons, I tell ya'!")); if (dm->dm_idx <= cdp->cdp_maxdirent && cdp->cdp_dirents[dm->dm_idx] != NULL) { de = cdp->cdp_dirents[dm->dm_idx]; KASSERT(cdp == de->de_cdp, ("inconsistent cdp")); continue; } cdp->cdp_inuse++; dev_unlock(); if (dm->dm_idx > cdp->cdp_maxdirent) devfs_metoo(cdp, dm); dd = dm->dm_rootdir; s = cdp->cdp_c.si_name; for (;;) { for (q = s; *q != '/' && *q != '\0'; q++) continue; if (*q != '/') break; de = devfs_find(dd, s, q - s, 0); if (de == NULL) de = devfs_vmkdir(dm, s, q - s, dd, 0); else if (de->de_dirent->d_type == DT_LNK) { de = devfs_find(dd, s, q - s, DT_DIR); if (de == NULL) de = devfs_vmkdir(dm, s, q - s, dd, 0); de->de_flags |= DE_COVERED; } s = q + 1; dd = de; KASSERT(dd->de_dirent->d_type == DT_DIR && (dd->de_flags & (DE_DOT | DE_DOTDOT)) == 0, ("%s: invalid directory (si_name=%s)", __func__, cdp->cdp_c.si_name)); } de_flags = 0; de = devfs_find(dd, s, q - s, DT_LNK); if (de != NULL) de_flags |= DE_COVERED; de = devfs_newdirent(s, q - s); if (cdp->cdp_c.si_flags & SI_ALIAS) { de->de_uid = 0; de->de_gid = 0; de->de_mode = 0755; de->de_dirent->d_type = DT_LNK; pdev = cdp->cdp_c.si_parent; j = strlen(pdev->si_name) + 1; de->de_symlink = malloc(j, M_DEVFS, M_WAITOK); bcopy(pdev->si_name, de->de_symlink, j); } else { de->de_uid = cdp->cdp_c.si_uid; de->de_gid = cdp->cdp_c.si_gid; de->de_mode = cdp->cdp_c.si_mode; de->de_dirent->d_type = DT_CHR; } de->de_flags |= de_flags; de->de_inode = cdp->cdp_inode; de->de_cdp = cdp; #ifdef MAC mac_devfs_create_device(cdp->cdp_c.si_cred, dm->dm_mount, &cdp->cdp_c, de); #endif de->de_dir = dd; TAILQ_INSERT_TAIL(&dd->de_dlist, de, de_list); devfs_rules_apply(dm, de); dev_lock(); /* XXX: could check that cdp is still active here */ KASSERT(cdp->cdp_dirents[dm->dm_idx] == NULL, ("%s %d\n", __func__, __LINE__)); cdp->cdp_dirents[dm->dm_idx] = de; KASSERT(de->de_cdp != (void *)0xdeadc0de, ("%s %d\n", __func__, __LINE__)); dev_unlock(); return (1); } dev_unlock(); return (0); } /* * The caller needs to hold the dm for the duration of the call. */ void devfs_populate(struct devfs_mount *dm) { unsigned gen; sx_assert(&dm->dm_lock, SX_XLOCKED); gen = devfs_generation; if (dm->dm_generation == gen) return; while (devfs_populate_loop(dm, 0)) continue; dm->dm_generation = gen; } /* * The caller needs to hold the dm for the duration of the call. */ void devfs_cleanup(struct devfs_mount *dm) { sx_assert(&dm->dm_lock, SX_XLOCKED); while (devfs_populate_loop(dm, 1)) continue; devfs_purge(dm, dm->dm_rootdir); } /* * devfs_create() and devfs_destroy() are called from kern_conf.c and * in both cases the devlock() mutex is held, so no further locking * is necesary and no sleeping allowed. */ void devfs_create(struct cdev *dev) { struct cdev_priv *cdp; mtx_assert(&devmtx, MA_OWNED); cdp = cdev2priv(dev); cdp->cdp_flags |= CDP_ACTIVE; cdp->cdp_inode = alloc_unrl(devfs_inos); dev_refl(dev); TAILQ_INSERT_TAIL(&cdevp_list, cdp, cdp_list); devfs_generation++; } void devfs_destroy(struct cdev *dev) { struct cdev_priv *cdp; mtx_assert(&devmtx, MA_OWNED); cdp = cdev2priv(dev); cdp->cdp_flags &= ~CDP_ACTIVE; devfs_generation++; } ino_t devfs_alloc_cdp_inode(void) { return (alloc_unr(devfs_inos)); } void devfs_free_cdp_inode(ino_t ino) { if (ino > 0) free_unr(devfs_inos, ino); } static void devfs_devs_init(void *junk __unused) { devfs_inos = new_unrhdr(DEVFS_ROOTINO + 1, INT_MAX, &devmtx); } SYSINIT(devfs_devs, SI_SUB_DEVFS, SI_ORDER_FIRST, devfs_devs_init, NULL);