diff options
Diffstat (limited to 'sys/kern/uipc_mqueue.c')
| -rw-r--r-- | sys/kern/uipc_mqueue.c | 2358 |
1 files changed, 2358 insertions, 0 deletions
diff --git a/sys/kern/uipc_mqueue.c b/sys/kern/uipc_mqueue.c new file mode 100644 index 000000000000..111bd0104bc2 --- /dev/null +++ b/sys/kern/uipc_mqueue.c @@ -0,0 +1,2358 @@ +/*- + * Copyright (c) 2005 David Xu <davidxu@freebsd.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + * + */ + +/* + * POSIX message queue implementation. + * + * 1) A mqueue filesystem can be mounted, each message queue appears + * in mounted directory, user can change queue's permission and + * ownership, or remove a queue. Manually creating a file in the + * directory causes a message queue to be created in the kernel with + * default message queue attributes applied and same name used, this + * method is not advocated since mq_open syscall allows user to specify + * different attributes. Also the file system can be mounted multiple + * times at different mount points but shows same contents. + * + * 2) Standard POSIX message queue API. The syscalls do not use vfs layer, + * but directly operate on internal data structure, this allows user to + * use the IPC facility without having to mount mqueue file system. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/limits.h> +#include <sys/buf.h> +#include <sys/dirent.h> +#include <sys/event.h> +#include <sys/fcntl.h> +#include <sys/filedesc.h> +#include <sys/file.h> +#include <sys/limits.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/module.h> +#include <sys/mount.h> +#include <sys/mqueue.h> +#include <sys/mutex.h> +#include <sys/namei.h> +#include <sys/poll.h> +#include <sys/proc.h> +#include <sys/queue.h> +#include <sys/sysproto.h> +#include <sys/stat.h> +#include <sys/sysent.h> +#include <sys/syscall.h> +#include <sys/syscallsubr.h> +#include <sys/sx.h> +#include <sys/sysctl.h> +#include <sys/sysctl.h> +#include <sys/vnode.h> +#include <sys/sysctl.h> +#include <sys/taskqueue.h> +#include <sys/unistd.h> +#include <sys/vnode.h> +#include <machine/atomic.h> + +/* + * Limits and constants + */ +#define MQFS_NAMELEN NAME_MAX +#define MQFS_DELEN (8 + MQFS_NAMELEN) + +/* node types */ +typedef enum { + mqfstype_none = 0, + mqfstype_root, + mqfstype_dir, + mqfstype_this, + mqfstype_parent, + mqfstype_file, + mqfstype_symlink, +} mqfs_type_t; + +struct mqfs_node; + +/* + * mqfs_info: describes a mqfs instance + */ +struct mqfs_info { + struct sx mi_lock; + struct mqfs_node *mi_root; + struct unrhdr *mi_unrhdr; +}; + +struct mqfs_vdata { + LIST_ENTRY(mqfs_vdata) mv_link; + struct mqfs_node *mv_node; + struct vnode *mv_vnode; + struct task mv_task; +}; + +/* + * mqfs_node: describes a node (file or directory) within a mqfs + */ +struct mqfs_node { + char mn_name[MQFS_NAMELEN+1]; + struct mqfs_info *mn_info; + struct mqfs_node *mn_parent; + LIST_HEAD(,mqfs_node) mn_children; + LIST_ENTRY(mqfs_node) mn_sibling; + LIST_HEAD(,mqfs_vdata) mn_vnodes; + int mn_refcount; + mqfs_type_t mn_type; + int mn_deleted; + u_int32_t mn_fileno; + void *mn_data; + struct timespec mn_birth; + struct timespec mn_ctime; + struct timespec mn_atime; + struct timespec mn_mtime; + uid_t mn_uid; + gid_t mn_gid; + int mn_mode; +}; + +#define VTON(vp) (((struct mqfs_vdata *)((vp)->v_data))->mv_node) +#define VTOMQ(vp) ((struct mqueue *)(VTON(vp)->mn_data)) +#define VFSTOMQFS(m) ((struct mqfs_info *)((m)->mnt_data)) +#define FPTOMQ(fp) (((struct mqueue_user *) \ + (fp)->f_data)->mu_node->mn_data) +TAILQ_HEAD(msgq, mqueue_msg); + +struct mqueue; +struct mqueue_user +{ + struct sigevent mu_sigev; + struct ksiginfo mu_ksi; + struct mqfs_node *mu_node; + struct proc *mu_proc; +}; + +struct mqueue { + struct mtx mq_mutex; + int mq_flags; + long mq_maxmsg; + long mq_msgsize; + long mq_curmsgs; + long mq_totalbytes; + struct msgq mq_msgq; + int mq_receivers; + int mq_senders; + struct selinfo mq_rsel; + struct selinfo mq_wsel; + struct mqueue_user *mq_notifier; +}; + +#define MQ_RSEL 0x01 +#define MQ_WSEL 0x02 + +struct mqueue_msg { + TAILQ_ENTRY(mqueue_msg) msg_link; + unsigned int msg_prio; + unsigned int msg_size; + /* following real data... */ +}; + +SYSCTL_NODE(_kern, OID_AUTO, mqueue, CTLFLAG_RW, 0, + "POSIX real time message queue"); + +static int default_maxmsg = 10; +static int default_msgsize = 1024; + +static int maxmsg = 20; +SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsg, CTLFLAG_RW, + &maxmsg, 0, "Default maximum messages in queue"); +static int maxmsgsize = 16384; +SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmsgsize, CTLFLAG_RW, + &maxmsgsize, 0, "Default maximum message size"); +static int maxmq = 100; +SYSCTL_INT(_kern_mqueue, OID_AUTO, maxmq, CTLFLAG_RW, + &maxmq, 0, "maximum message queues"); +static int curmq = 0; +SYSCTL_INT(_kern_mqueue, OID_AUTO, curmq, CTLFLAG_RW, + &curmq, 0, "current message queue number"); +static int unloadable = 0; +static MALLOC_DEFINE(M_MQUEUEDATA, "mqdata", "mqueue data"); + +/* Only one instance per-system */ +static struct mqfs_info mqfs_data; +static uma_zone_t mqnode_zone; +static uma_zone_t mqueue_zone; +static uma_zone_t mvdata_zone; +static uma_zone_t mquser_zone; +static struct vop_vector mqfs_vnodeops; +static struct fileops mqueueops; + +/* + * Directory structure construction and manipulation + */ +#ifdef notyet +static struct mqfs_node *mqfs_create_dir(struct mqfs_node *parent, + const char *name, int namelen); +#endif + +static struct mqfs_node *mqfs_create_file(struct mqfs_node *parent, + const char *name, int namelen); +struct mqfs_node *mqfs_create_link(struct mqfs_node *parent, + const char *name, int namelen); +static int mqfs_destroy(struct mqfs_node *mn); +static void mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn); +static void mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn); +static int mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn); + +/* + * Message queue construction and maniplation + */ +static struct mqueue *mqueue_alloc(const struct mq_attr *attr); +static void mqueue_free(struct mqueue *mq); +static int mqueue_send(struct mqueue *mq, const char *msg_ptr, + size_t msg_len, unsigned msg_prio, int waitok, + const struct timespec *abs_timeout); +static int mqueue_receive(struct mqueue *mq, char *msg_ptr, + size_t msg_len, unsigned *msg_prio, int waitok, + const struct timespec *abs_timeout); +static int _mqueue_send(struct mqueue *mq, struct mqueue_msg *msg, + int timo); +static int _mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg, + int timo); +static void mqueue_send_notification(struct mqueue *mq); + +/* kqueue filters */ +static void filt_mqdetach(struct knote *kn); +static int filt_mqread(struct knote *kn, long hint); +static int filt_mqwrite(struct knote *kn, long hint); + +struct filterops mq_rfiltops = + { 1, NULL, filt_mqdetach, filt_mqread }; +struct filterops mq_wfiltops = + { 1, NULL, filt_mqdetach, filt_mqwrite }; + +/* + * Initialize fileno bitmap + */ +static void +mqfs_fileno_init(struct mqfs_info *mi) +{ + struct unrhdr *up; + + up = new_unrhdr(1, INT_MAX, NULL); + mi->mi_unrhdr = up; +} + +/* + * Tear down fileno bitmap + */ +static void +mqfs_fileno_uninit(struct mqfs_info *mi) +{ + struct unrhdr *up; + + up = mi->mi_unrhdr; + mi->mi_unrhdr = NULL; + delete_unrhdr(up); + + uma_zdestroy(mqnode_zone); + uma_zdestroy(mqueue_zone); + uma_zdestroy(mvdata_zone); + uma_zdestroy(mquser_zone); +} + +/* + * Allocate a file number + */ +void +mqfs_fileno_alloc(struct mqfs_info *mi, struct mqfs_node *mn) +{ + /* make sure our parent has a file number */ + if (mn->mn_parent && !mn->mn_parent->mn_fileno) + mqfs_fileno_alloc(mi, mn->mn_parent); + + switch (mn->mn_type) { + case mqfstype_root: + case mqfstype_dir: + case mqfstype_file: + case mqfstype_symlink: + mn->mn_fileno = alloc_unr(mi->mi_unrhdr); + break; + case mqfstype_this: + KASSERT(mn->mn_parent != NULL, + ("mqfstype_this node has no parent")); + mn->mn_fileno = mn->mn_parent->mn_fileno; + break; + case mqfstype_parent: + KASSERT(mn->mn_parent != NULL, + ("mqfstype_parent node has no parent")); + if (mn->mn_parent == mi->mi_root) { + mn->mn_fileno = mn->mn_parent->mn_fileno; + break; + } + KASSERT(mn->mn_parent->mn_parent != NULL, + ("mqfstype_parent node has no grandparent")); + mn->mn_fileno = mn->mn_parent->mn_parent->mn_fileno; + break; + default: + KASSERT(0, + ("mqfs_fileno_alloc() called for unknown type node: %d", + mn->mn_type)); + break; + } +} + +/* + * Release a file number + */ +void +mqfs_fileno_free(struct mqfs_info *mi, struct mqfs_node *mn) +{ + switch (mn->mn_type) { + case mqfstype_root: + case mqfstype_dir: + case mqfstype_file: + case mqfstype_symlink: + free_unr(mi->mi_unrhdr, mn->mn_fileno); + break; + case mqfstype_this: + case mqfstype_parent: + /* ignore these, as they don't "own" their file number */ + break; + default: + KASSERT(0, + ("mqfs_fileno_free() called for unknown type node: %d", + mn->mn_type)); + break; + } +} + +static __inline struct mqfs_node * +mqnode_alloc(void) +{ + return uma_zalloc(mqnode_zone, M_WAITOK | M_ZERO); +} + +static __inline void +mqnode_free(struct mqfs_node *node) +{ + uma_zfree(mqnode_zone, node); +} + +static __inline void +mqnode_addref(struct mqfs_node *node) +{ + atomic_fetchadd_int(&node->mn_refcount, 1); +} + +static __inline void +mqnode_release(struct mqfs_node *node) +{ + int old, exp; + + old = atomic_fetchadd_int(&node->mn_refcount, -1); + if (node->mn_type == mqfstype_dir || + node->mn_type == mqfstype_root) + exp = 3; /* include . and .. */ + else + exp = 1; + if (old == exp) + mqfs_destroy(node); +} + +/* + * Add a node to a directory + */ +static int +mqfs_add_node(struct mqfs_node *parent, struct mqfs_node *node) +{ + KASSERT(parent != NULL, ("%s(): parent is NULL", __func__)); + KASSERT(parent->mn_info != NULL, + ("%s(): parent has no mn_info", __func__)); + KASSERT(parent->mn_type == mqfstype_dir || + parent->mn_type == mqfstype_root, + ("%s(): parent is not a directory", __func__)); + + node->mn_info = parent->mn_info; + node->mn_parent = parent; + LIST_INIT(&node->mn_children); + LIST_INIT(&node->mn_vnodes); + LIST_INSERT_HEAD(&parent->mn_children, node, mn_sibling); + mqnode_addref(parent); + return (0); +} + +/* + * Add . and .. to a directory + */ +static int +mqfs_fixup_dir(struct mqfs_node *parent) +{ + struct mqfs_node *dir; + + dir = mqnode_alloc(); + dir->mn_name[0] = '.'; + dir->mn_type = mqfstype_this; + dir->mn_refcount = 1; + if (mqfs_add_node(parent, dir) != 0) { + mqnode_free(dir); + return (-1); + } + + dir = mqnode_alloc(); + dir->mn_name[0] = dir->mn_name[1] = '.'; + dir->mn_type = mqfstype_parent; + dir->mn_refcount = 1; + + if (mqfs_add_node(parent, dir) != 0) { + mqnode_free(dir); + return (-1); + } + + return (0); +} + +#ifdef notyet + +/* + * Create a directory + */ +struct mqfs_node * +mqfs_create_dir(struct mqfs_node *parent, const char *name, int namelen) +{ + struct mqfs_node *dir; + + dir = mqnode_alloc(); + strncpy(dir->mn_name, name, namelen); + dir->mn_type = mqfstype_dir; + dir->mn_refcount = 1; + if (mqfs_add_node(parent, dir) != 0) { + mqnode_free(dir); + return (NULL); + } + + if (mqfs_fixup_dir(dir) != 0) { + mqfs_destroy(dir); + return (NULL); + } + + return (dir); +} +#endif + +/* + * Create a file + */ +struct mqfs_node * +mqfs_create_file(struct mqfs_node *parent, const char *name, int namelen) +{ + struct mqfs_node *node; + + node = mqnode_alloc(); + strncpy(node->mn_name, name, namelen); + node->mn_type = mqfstype_file; + node->mn_refcount = 1; + + if (mqfs_add_node(parent, node) != 0) { + mqnode_free(node); + return (NULL); + } + return (node); +} + +/* + * Create a symlink + */ +struct mqfs_node * +mqfs_create_link(struct mqfs_node *parent, const char *name, int namelen) +{ + struct mqfs_node *node; + + node = mqfs_create_file(parent, name, namelen); + if (node == NULL) + return (NULL); + node->mn_type = mqfstype_symlink; + return (node); +} + +/* + * Destroy a node or a tree of nodes + */ +int +mqfs_destroy(struct mqfs_node *node) +{ + struct mqfs_node *parent; + + KASSERT(node != NULL, + ("%s(): node is NULL", __func__)); + KASSERT(node->mn_info != NULL, + ("%s(): node has no mn_info", __func__)); + + /* destroy children */ + if (node->mn_type == mqfstype_dir || node->mn_type == mqfstype_root) + while (! LIST_EMPTY(&node->mn_children)) + mqfs_destroy(LIST_FIRST(&node->mn_children)); + + /* unlink from parent */ + if ((parent = node->mn_parent) != NULL) { + KASSERT(parent->mn_info == node->mn_info, + ("%s(): parent has different mn_info", __func__)); + LIST_REMOVE(node, mn_sibling); + } + + if (node->mn_fileno != 0) + mqfs_fileno_free(node->mn_info, node); + if (node->mn_data != NULL) + mqueue_free(node->mn_data); + mqnode_free(node); + return (0); +} + +/* + * Mount a mqfs instance + */ +static int +mqfs_mount(struct mount *mp, struct thread *td) +{ + struct statfs *sbp; + + if (mp->mnt_flag & MNT_UPDATE) + return (EOPNOTSUPP); + + mp->mnt_data = &mqfs_data; + mp->mnt_flag |= MNT_LOCAL; + /* mp->mnt_kern_flag |= MNTK_MPSAFE; */ + vfs_getnewfsid(mp); + + sbp = &mp->mnt_stat; + vfs_mountedfrom(mp, "mqueue"); + sbp->f_bsize = PAGE_SIZE; + sbp->f_iosize = PAGE_SIZE; + sbp->f_blocks = 1; + sbp->f_bfree = 0; + sbp->f_bavail = 0; + sbp->f_files = 1; + sbp->f_ffree = 0; + return (0); +} + +/* + * Unmount a mqfs instance + */ +static int +mqfs_unmount(struct mount *mp, int mntflags, struct thread *td) +{ + int error; + + error = vflush(mp, 0, (mntflags & MNT_FORCE) ? FORCECLOSE : 0, td); + return (error); +} + +/* + * Return a root vnode + */ +static int +mqfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) +{ + struct mqfs_info *mqfs; + int ret; + + mqfs = VFSTOMQFS(mp); + sx_xlock(&mqfs->mi_lock); + ret = mqfs_allocv(mp, vpp, mqfs->mi_root); + sx_xunlock(&mqfs->mi_lock); + return (ret); +} + +/* + * Return filesystem stats + */ +static int +mqfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) +{ + /* XXX update statistics */ + return (0); +} + +/* + * Initialize a mqfs instance + */ +static int +mqfs_init(struct vfsconf *vfc) +{ + struct mqfs_node *root; + struct mqfs_info *mi; + + mqnode_zone = uma_zcreate("mqnode", sizeof(struct mqfs_node), + NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); + mqueue_zone = uma_zcreate("mqueue", sizeof(struct mqueue), + NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); + mvdata_zone = uma_zcreate("mvdata", + sizeof(struct mqfs_vdata), NULL, NULL, NULL, + NULL, UMA_ALIGN_PTR, 0); + mquser_zone = uma_zcreate("mquser", sizeof(struct mqueue_user), + NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); + mi = &mqfs_data; + sx_init(&mi->mi_lock, "mqfs lock"); + /* set up the root diretory */ + root = mqnode_alloc(); + root->mn_type = mqfstype_root; + root->mn_refcount = 1; + root->mn_name[0] = '/'; + root->mn_info = mi; + LIST_INIT(&root->mn_children); + LIST_INIT(&root->mn_vnodes); + root->mn_mode = 01777; + mi->mi_root = root; + mqfs_fileno_init(mi); + mqfs_fileno_alloc(mi, root); + mqfs_fixup_dir(root); + return (0); +} + +/* + * Destroy a mqfs instance + */ +static int +mqfs_uninit(struct vfsconf *vfc) +{ + struct mqfs_info *mi; + + if (!unloadable) + return (EOPNOTSUPP); + mi = &mqfs_data; + mqfs_destroy(mi->mi_root); + mi->mi_root = NULL; + mqfs_fileno_uninit(mi); + sx_destroy(&mi->mi_lock); + return (0); +} + +/* + * task routine + */ +static void +do_recycle(void *context, int pending __unused) +{ + struct vnode *vp = (struct vnode *)context; + + vrecycle(vp, curthread); + vdrop(vp); +} + +/* + * Allocate a vnode + */ +int +mqfs_allocv(struct mount *mp, struct vnode **vpp, struct mqfs_node *pn) +{ + struct mqfs_vdata *vd; + int error; + + LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) { + if (vd->mv_vnode->v_mount == mp) + break; + } + + if (vd != NULL) { + if (vget(vd->mv_vnode, 0, curthread) == 0) { + *vpp = vd->mv_vnode; + vn_lock(*vpp, LK_RETRY | LK_EXCLUSIVE, + curthread); + return (0); + } + /* XXX if this can happen, we're in trouble */ + } + + error = getnewvnode("mqueue", mp, &mqfs_vnodeops, vpp); + if (error) + return (error); + vd = uma_zalloc(mvdata_zone, M_WAITOK); + (*vpp)->v_data = vd; + vd->mv_vnode = *vpp; + vd->mv_node = pn; + TASK_INIT(&vd->mv_task, 0, do_recycle, *vpp); + LIST_INSERT_HEAD(&pn->mn_vnodes, vd, mv_link); + mqnode_addref(pn); + switch (pn->mn_type) { + case mqfstype_root: + (*vpp)->v_vflag = VV_ROOT; + /* fall through */ + case mqfstype_dir: + case mqfstype_this: + case mqfstype_parent: + (*vpp)->v_type = VDIR; + break; + case mqfstype_file: + (*vpp)->v_type = VREG; + break; + case mqfstype_symlink: + (*vpp)->v_type = VLNK; + break; + case mqfstype_none: + KASSERT(0, ("mqfs_allocf called for null node\n")); + default: + panic("%s has unexpected type: %d", pn->mn_name, pn->mn_type); + } + vn_lock(*vpp, LK_RETRY | LK_EXCLUSIVE, curthread); + return (0); +} + +/* + * Search a directory entry + */ +static struct mqfs_node * +mqfs_search(struct mqfs_node *pd, const char *name, int len) +{ + struct mqfs_node *pn; + + LIST_FOREACH(pn, &pd->mn_children, mn_sibling) { + if (strncmp(pn->mn_name, name, len) == 0) + return (pn); + } + return (NULL); +} + +/* + * Look up a file or directory + */ +static int +mqfs_lookupx(struct vop_cachedlookup_args *ap) +{ + struct componentname *cnp; + struct vnode *dvp, **vpp; + struct mqfs_node *pd; + struct mqfs_node *pn; + int nameiop, flags, error, namelen; + char *pname; + struct thread *td; + + cnp = ap->a_cnp; + vpp = ap->a_vpp; + dvp = ap->a_dvp; + pname = cnp->cn_nameptr; + namelen = cnp->cn_namelen; + td = cnp->cn_thread; + flags = cnp->cn_flags; + nameiop = cnp->cn_nameiop; + pd = VTON(dvp); + pn = NULL; + *vpp = NULLVP; + + if (dvp->v_type != VDIR) + return (ENOTDIR); + + error = VOP_ACCESS(dvp, VEXEC, cnp->cn_cred, cnp->cn_thread); + if (error) + return (error); + + /* shortcut: check if the name is too long */ + if (cnp->cn_namelen >= MQFS_NAMELEN) + return (ENOENT); + + /* self */ + if (namelen == 1 && pname[0] == '.') { + if ((flags & ISLASTCN) && nameiop != LOOKUP) + return (EINVAL); + pn = pd; + *vpp = dvp; + VREF(dvp); + return (0); + } + + /* parent */ + if (cnp->cn_flags & ISDOTDOT) { + if (dvp->v_vflag & VV_ROOT) + return (EIO); + if ((flags & ISLASTCN) && nameiop != LOOKUP) + return (EINVAL); + VOP_UNLOCK(dvp, 0, cnp->cn_thread); + KASSERT(pd->mn_parent, ("non-root directory has no parent")); + pn = pd->mn_parent; + error = mqfs_allocv(dvp->v_mount, vpp, pn); + vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td); + return (error); + } + + /* named node */ + pn = mqfs_search(pd, pname, namelen); + + /* found */ + if (pn != NULL) { + /* DELETE */ + if (nameiop == DELETE && (flags & ISLASTCN)) { + error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); + if (error) + return (error); + if (*vpp == dvp) { + VREF(dvp); + *vpp = dvp; + return (0); + } + } + + /* allocate vnode */ + error = mqfs_allocv(dvp->v_mount, vpp, pn); + if (error == 0 && cnp->cn_flags & MAKEENTRY) + cache_enter(dvp, *vpp, cnp); + return (error); + } + + /* not found */ + + /* will create a new entry in the directory ? */ + if ((nameiop == CREATE || nameiop == RENAME) && (flags & LOCKPARENT) + && (flags & ISLASTCN)) { + error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, td); + if (error) + return (error); + cnp->cn_flags |= SAVENAME; + return (EJUSTRETURN); + } + return (ENOENT); +} + +#if 0 +struct vop_lookup_args { + struct vop_generic_args a_gen; + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; +}; +#endif + +/* + * vnode lookup operation + */ +static int +mqfs_lookup(struct vop_cachedlookup_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount); + int rc; + + sx_xlock(&mqfs->mi_lock); + rc = mqfs_lookupx(ap); + sx_xunlock(&mqfs->mi_lock); + return (rc); +} + +#if 0 +struct vop_create_args { + struct vnode *a_dvp; + struct vnode **a_vpp; + struct componentname *a_cnp; + struct vattr *a_vap; +}; +#endif + +/* + * vnode creation operation + */ +static int +mqfs_create(struct vop_create_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount); + struct componentname *cnp = ap->a_cnp; + struct mqfs_node *pd; + struct mqfs_node *pn; + struct mqueue *mq; + int error; + + pd = VTON(ap->a_dvp); + if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir) + return (ENOTDIR); + mq = mqueue_alloc(NULL); + if (mq == NULL) + return (EAGAIN); + sx_xlock(&mqfs->mi_lock); +#if 0 + /* named node */ + pn = mqfs_search(pd, cnp->cn_nameptr, cnp->cn_namelen); + if (pn != NULL) { + mqueue_free(mq); + sx_xunlock(&mqfs->mi_lock); + return (EEXIST); + } +#else + if ((cnp->cn_flags & HASBUF) == 0) + panic("%s: no name", __func__); +#endif + pn = mqfs_create_file(pd, cnp->cn_nameptr, cnp->cn_namelen); + pn->mn_mode = ap->a_vap->va_mode; + pn->mn_uid = cnp->cn_cred->cr_uid; + pn->mn_gid = cnp->cn_cred->cr_gid; + pn->mn_data = mq; + getnanotime(&pn->mn_birth); + pn->mn_ctime = pn->mn_atime = pn->mn_mtime = pn->mn_birth; + /* node attribute */ + error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn); + sx_xunlock(&mqfs->mi_lock); + return (error); +} + +/* + * Remove an entry + */ +static +int do_unlink(struct mqfs_node *pn, struct ucred *ucred) +{ + struct mqfs_node *parent; + struct mqfs_vdata *vd; + int error = 0; + + sx_assert(&pn->mn_info->mi_lock, SX_LOCKED); + + if (ucred->cr_uid != pn->mn_uid && + (error = suser_cred(ucred, 0)) != 0) + error = EACCES; + else if (!pn->mn_deleted) { + parent = pn->mn_parent; + pn->mn_parent = NULL; + pn->mn_deleted = 1; + LIST_REMOVE(pn, mn_sibling); + LIST_FOREACH(vd, &pn->mn_vnodes, mv_link) { + cache_purge(vd->mv_vnode); + vhold(vd->mv_vnode); + taskqueue_enqueue(taskqueue_thread, &vd->mv_task); + } + mqnode_release(pn); + mqnode_release(parent); + } else + error = ENOENT; + return (error); +} + +#if 0 +struct vop_remove_args { + struct vnode *a_dvp; + struct vnode *a_vp; + struct componentname *a_cnp; +}; +#endif + +/* + * vnode removal operation + */ +static int +mqfs_remove(struct vop_remove_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount); + struct mqfs_node *pn; + int error; + + if (ap->a_vp->v_type == VDIR) + return (EPERM); + pn = VTON(ap->a_vp); + sx_xlock(&mqfs->mi_lock); + error = do_unlink(pn, ap->a_cnp->cn_cred); + sx_xunlock(&mqfs->mi_lock); + return (error); +} + +#if 0 +struct vop_inactive_args { + struct vnode *a_vp; + struct thread *a_td; +}; +#endif + +static int +mqfs_inactive(struct vop_inactive_args *ap) +{ + struct mqfs_node *pn = VTON(ap->a_vp); + + if (pn->mn_deleted) + vrecycle(ap->a_vp, ap->a_td); + return (0); +} + +#if 0 +struct vop_reclaim_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + struct thread *a_td; +}; +#endif + +static int +mqfs_reclaim(struct vop_reclaim_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_vp->v_mount); + struct vnode *vp = ap->a_vp; + struct mqfs_node *pn; + struct mqfs_vdata *vd; + + vd = vp->v_data; + pn = vd->mv_node; + sx_xlock(&mqfs->mi_lock); + vp->v_data = NULL; + LIST_REMOVE(vd, mv_link); + uma_zfree(mvdata_zone, vd); + mqnode_release(pn); + sx_xunlock(&mqfs->mi_lock); + return (0); +} + +#if 0 +struct vop_open_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct thread *a_td; + int a_fdidx; +}; +#endif + +static int +mqfs_open(struct vop_open_args *ap) +{ + return (0); +} + +#if 0 +struct vop_close_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + int a_fflag; + struct ucred *a_cred; + struct thread *a_td; +}; +#endif + +static int +mqfs_close(struct vop_close_args *ap) +{ + return (0); +} + +#if 0 +struct vop_access_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + int a_mode; + struct ucred *a_cred; + struct thread *a_td; +}; +#endif + +/* + * Verify permissions + */ +static int +mqfs_access(struct vop_access_args *ap) +{ + struct vnode *vp = ap->a_vp; + struct vattr vattr; + int error; + + error = VOP_GETATTR(vp, &vattr, ap->a_cred, ap->a_td); + if (error) + return (error); + error = vaccess(vp->v_type, vattr.va_mode, vattr.va_uid, + vattr.va_gid, ap->a_mode, ap->a_cred, NULL); + return (error); +} + +#if 0 +struct vop_getattr_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + struct vattr *a_vap; + struct ucred *a_cred; + struct thread *a_td; +}; +#endif + +/* + * Get file attributes + */ +static int +mqfs_getattr(struct vop_getattr_args *ap) +{ + struct vnode *vp = ap->a_vp; + struct mqfs_node *pn = VTON(vp); + struct vattr *vap = ap->a_vap; + int error = 0; + + VATTR_NULL(vap); + vap->va_type = vp->v_type; + vap->va_mode = pn->mn_mode; + vap->va_nlink = 1; + vap->va_uid = pn->mn_uid; + vap->va_gid = pn->mn_gid; + vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; + vap->va_fileid = pn->mn_fileno; + vap->va_size = 0; + vap->va_blocksize = PAGE_SIZE; + vap->va_bytes = vap->va_size = 0; + vap->va_atime = pn->mn_atime; + vap->va_mtime = pn->mn_mtime; + vap->va_ctime = pn->mn_ctime; + vap->va_birthtime = pn->mn_birth; + vap->va_gen = 0; + vap->va_flags = 0; + vap->va_rdev = 0; + vap->va_bytes = 0; + vap->va_filerev = 0; + vap->va_vaflags = 0; + return (error); +} + +#if 0 +struct vop_setattr_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + struct vattr *a_vap; + struct ucred *a_cred; + struct thread *a_td; +}; +#endif +/* + * Set attributes + */ +static int +mqfs_setattr(struct vop_setattr_args *ap) +{ + struct mqfs_node *pn; + struct vattr *vap; + struct vnode *vp; + int c, error; + uid_t uid; + gid_t gid; + + vap = ap->a_vap; + vp = ap->a_vp; + if ((vap->va_type != VNON) || + (vap->va_nlink != VNOVAL) || + (vap->va_fsid != VNOVAL) || + (vap->va_fileid != VNOVAL) || + (vap->va_blocksize != VNOVAL) || + (vap->va_flags != VNOVAL && vap->va_flags != 0) || + (vap->va_rdev != VNOVAL) || + ((int)vap->va_bytes != VNOVAL) || + (vap->va_gen != VNOVAL)) { + return (EINVAL); + } + + pn = VTON(vp); + + error = c = 0; + if (vap->va_uid == (uid_t)VNOVAL) + uid = pn->mn_uid; + else + uid = vap->va_uid; + if (vap->va_gid == (gid_t)VNOVAL) + gid = pn->mn_gid; + else + gid = vap->va_gid; + + if (uid != pn->mn_uid || gid != pn->mn_gid) { + /* + * To modify the ownership of a file, must possess VADMIN + * for that file. + */ + if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, ap->a_td))) + return (error); + if (((ap->a_cred->cr_uid != pn->mn_uid) || uid != pn->mn_uid || + (gid != pn->mn_gid && !groupmember(gid, ap->a_cred))) && + (error = suser_cred(ap->a_td->td_ucred, SUSER_ALLOWJAIL)) + != 0) + return (error); + pn->mn_uid = uid; + pn->mn_gid = gid; + c = 1; + } + + if (vap->va_mode != (mode_t)VNOVAL) { + if ((ap->a_cred->cr_uid != pn->mn_uid) && + (error = suser_cred(ap->a_td->td_ucred, SUSER_ALLOWJAIL))) + return (error); + pn->mn_mode = vap->va_mode; + c = 1; + } + + if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { + /* See the comment in ufs_vnops::ufs_setattr(). */ + if ((error = VOP_ACCESS(vp, VADMIN, ap->a_cred, ap->a_td)) && + ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || + (error = VOP_ACCESS(vp, VWRITE, ap->a_cred, ap->a_td)))) + return (error); + if (vap->va_atime.tv_sec != VNOVAL) { + pn->mn_atime = vap->va_atime; + } + if (vap->va_mtime.tv_sec != VNOVAL) { + pn->mn_mtime = vap->va_mtime; + } + c = 1; + } + if (c) { + vfs_timestamp(&pn->mn_ctime); + } + return (0); +} + +#if 0 +struct vop_read_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + struct uio *a_uio; + int a_ioflag; + struct ucred *a_cred; +}; +#endif + +/* + * Read from a file + */ +static int +mqfs_read(struct vop_read_args *ap) +{ + char buf[80]; + struct vnode *vp = ap->a_vp; + struct uio *uio = ap->a_uio; + struct mqfs_node *pn; + struct mqueue *mq; + int len, error; + + if (vp->v_type != VREG) + return (EINVAL); + + pn = VTON(vp); + mq = VTOMQ(vp); + snprintf(buf, sizeof(buf), + "QSIZE:%-10ld MAXMSG:%-10ld CURMSG:%-10ld MSGSIZE:%-10ld\n", + mq->mq_totalbytes, + mq->mq_maxmsg, + mq->mq_curmsgs, + mq->mq_msgsize); + buf[sizeof(buf)-1] = '\0'; + len = strlen(buf); + error = uiomove_frombuf(buf, len, uio); + return (error); +} + +#if 0 +struct vop_readdir_args { + struct vop_generic_args a_gen; + struct vnode *a_vp; + struct uio *a_uio; + struct ucred *a_cred; + int *a_eofflag; + int *a_ncookies; + u_long **a_cookies; +}; +#endif + +/* + * Return directory entries. + */ +static int +mqfs_readdir(struct vop_readdir_args *ap) +{ + struct vnode *vp; + struct mqfs_info *mi; + struct mqfs_node *pd; + struct mqfs_node *pn; + struct dirent entry; + struct uio *uio; + int *tmp_ncookies = NULL; + off_t offset; + int error, i; + + vp = ap->a_vp; + mi = VFSTOMQFS(vp->v_mount); + pd = VTON(vp); + uio = ap->a_uio; + + if (vp->v_type != VDIR) + return (ENOTDIR); + + if (uio->uio_offset < 0) + return (EINVAL); + + if (ap->a_ncookies != NULL) { + tmp_ncookies = ap->a_ncookies; + *ap->a_ncookies = 0; + ap->a_ncookies = NULL; + } + + error = 0; + offset = 0; + + sx_xlock(&mi->mi_lock); + + LIST_FOREACH(pn, &pd->mn_children, mn_sibling) { + entry.d_reclen = sizeof(entry); + if (!pn->mn_fileno) + mqfs_fileno_alloc(mi, pn); + entry.d_fileno = pn->mn_fileno; + for (i = 0; i < MQFS_NAMELEN - 1 && pn->mn_name[i] != '\0'; ++i) + entry.d_name[i] = pn->mn_name[i]; + entry.d_name[i] = 0; + entry.d_namlen = i; + switch (pn->mn_type) { + case mqfstype_root: + case mqfstype_dir: + case mqfstype_this: + case mqfstype_parent: + entry.d_type = DT_DIR; + break; + case mqfstype_file: + entry.d_type = DT_REG; + break; + case mqfstype_symlink: + entry.d_type = DT_LNK; + break; + default: + panic("%s has unexpected node type: %d", pn->mn_name, + pn->mn_type); + } + if (entry.d_reclen > uio->uio_resid) + break; + if (offset >= uio->uio_offset) { + error = vfs_read_dirent(ap, &entry, offset); + if (error) + break; + } + offset += entry.d_reclen; + } + sx_xunlock(&mi->mi_lock); + + uio->uio_offset = offset; + + if (tmp_ncookies != NULL) + ap->a_ncookies = tmp_ncookies; + + return (error); +} + +#ifdef notyet + +#if 0 +struct vop_mkdir_args { + struct vnode *a_dvp; + struvt vnode **a_vpp; + struvt componentname *a_cnp; + struct vattr *a_vap; +}; +#endif + +/* + * Create a directory. + */ +static int +mqfs_mkdir(struct vop_mkdir_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount); + struct componentname *cnp = ap->a_cnp; + struct mqfs_node *pd = VTON(ap->a_dvp); + struct mqfs_node *pn; + int error; + + if (pd->mn_type != mqfstype_root && pd->mn_type != mqfstype_dir) + return (ENOTDIR); + sx_xlock(&mqfs->mi_lock); +#if 0 + /* named node */ + pn = mqfs_search(pd, cnp->cn_nameptr, cnp->cn_namelen); + if (pn != NULL) { + sx_xunlock(&mqfs->mi_lock); + return (EEXIST); + } +#else + if ((cnp->cn_flags & HASBUF) == 0) + panic("%s: no name", __func__); +#endif + pn = mqfs_create_dir(pd, cnp->cn_nameptr, cnp->cn_namelen); + pn->mn_mode = ap->a_vap->va_mode; + pn->mn_uid = cnp->cn_cred->cr_uid; + pn->mn_gid = cnp->cn_cred->cr_gid; + getnanotime(&pn->mn_birth); + pn->mn_ctime = pn->mn_atime = pn->mn_mtime = pn->mn_birth; + /* node attribute */ + error = mqfs_allocv(ap->a_dvp->v_mount, ap->a_vpp, pn); + sx_xunlock(&mqfs->mi_lock); + return (error); +} + +#if 0 +struct vop_rmdir_args { + struct vnode *a_dvp; + struct vnode *a_vp; + struct componentname *a_cnp; +}; +#endif + +/* + * Remove a directory. + */ +static int +mqfs_rmdir(struct vop_rmdir_args *ap) +{ + struct mqfs_info *mqfs = VFSTOMQFS(ap->a_dvp->v_mount); + struct mqfs_node *pn = VTON(ap->a_vp); + struct mqfs_node *pt; + + if (pn->mn_type != mqfstype_dir) + return (ENOTDIR); + + sx_xlock(&mqfs->mi_lock); + if (pn->mn_deleted) { + sx_xunlock(&mqfs->mi_lock); + return (ENOENT); + } + + pt = LIST_FIRST(&pn->mn_children); + pt = LIST_NEXT(pt, mn_sibling); + pt = LIST_NEXT(pt, mn_sibling); + if (pt != NULL) { + sx_xunlock(&mqfs->mi_lock); + return (ENOTEMPTY); + } + pt = pn->mn_parent; + pn->mn_parent = NULL; + pn->mn_deleted = 1; + LIST_REMOVE(pn, mn_sibling); + mqnode_release(pn); + mqnode_release(pt); + sx_xunlock(&mqfs->mi_lock); + cache_purge(ap->a_vp); + return (0); +} + +#endif /* notyet */ + +/* + * Allocate a message queue + */ +static struct mqueue * +mqueue_alloc(const struct mq_attr *attr) +{ + struct mqueue *mq; + + if (curmq >= maxmq) + return (NULL); + mq = uma_zalloc(mqueue_zone, M_WAITOK | M_ZERO); + TAILQ_INIT(&mq->mq_msgq); + if (attr != NULL) { + mq->mq_maxmsg = attr->mq_maxmsg; + mq->mq_msgsize = attr->mq_msgsize; + } else { + mq->mq_maxmsg = default_maxmsg; + mq->mq_msgsize = default_msgsize; + } + mtx_init(&mq->mq_mutex, "mqueue", NULL, MTX_DEF); + knlist_init(&mq->mq_rsel.si_note, &mq->mq_mutex, NULL, NULL, NULL); + knlist_init(&mq->mq_wsel.si_note, &mq->mq_mutex, NULL, NULL, NULL); + atomic_add_int(&curmq, 1); + return (mq); +} + +/* + * Destroy a message queue + */ +static void +mqueue_free(struct mqueue *mq) +{ + struct mqueue_msg *msg; + + while ((msg = TAILQ_FIRST(&mq->mq_msgq)) != NULL) { + TAILQ_REMOVE(&mq->mq_msgq, msg, msg_link); + FREE(msg, M_MQUEUEDATA); + } + + mtx_destroy(&mq->mq_mutex); + knlist_destroy(&mq->mq_rsel.si_note); + knlist_destroy(&mq->mq_wsel.si_note); + uma_zfree(mqueue_zone, mq); + atomic_add_int(&curmq, -1); +} + +/* + * Load a message from user space + */ +static struct mqueue_msg * +mqueue_loadmsg(const char *msg_ptr, size_t msg_size, int msg_prio) +{ + struct mqueue_msg *msg; + size_t len; + int error; + + len = sizeof(struct mqueue_msg) + msg_size; + MALLOC(msg, struct mqueue_msg *, len, M_MQUEUEDATA, M_WAITOK); + error = copyin(msg_ptr, ((char *)msg) + sizeof(struct mqueue_msg), + msg_size); + if (error) { + FREE(msg, M_MQUEUEDATA); + msg = NULL; + } else { + msg->msg_size = msg_size; + msg->msg_prio = msg_prio; + } + return (msg); +} + +/* + * Save a message to user space + */ +static int +mqueue_savemsg(struct mqueue_msg *msg, char *msg_ptr, int *msg_prio) +{ + int error; + + error = copyout(((char *)msg) + sizeof(*msg), msg_ptr, + msg->msg_size); + if (error == 0) + error = copyout(&msg->msg_prio, msg_prio, sizeof(int)); + return (error); +} + +/* + * Free a message's memory + */ +static __inline void +mqueue_freemsg(struct mqueue_msg *msg) +{ + FREE(msg, M_MQUEUEDATA); +} + +/* + * Send a message. if waitok is false, thread will not be + * blocked if there is no data in queue, otherwise, absolute + * time will be checked. + */ +int +mqueue_send(struct mqueue *mq, const char *msg_ptr, + size_t msg_len, unsigned msg_prio, int waitok, + const struct timespec *abs_timeout) +{ + struct mqueue_msg *msg; + struct timespec ets, ts, ts2; + struct timeval tv; + int error; + + if (msg_len > mq->mq_msgsize) + return (EMSGSIZE); + msg = mqueue_loadmsg(msg_ptr, msg_len, msg_prio); + if (msg == NULL) + return (EFAULT); + + /* O_NONBLOCK case */ + if (!waitok) { + error = _mqueue_send(mq, msg, -1); + if (error) + goto bad; + return (0); + } + + /* we allow a null timeout (wait forever) */ + if (abs_timeout == NULL) { + error = _mqueue_send(mq, msg, 0); + if (error) + goto bad; + return (0); + } + + /* send it before checking time */ + error = _mqueue_send(mq, msg, -1); + if (error == 0) + return (0); + + if (error != EAGAIN) + goto bad; + + error = copyin(abs_timeout, &ets, sizeof(ets)); + if (error != 0) + goto bad; + if (ets.tv_nsec >= 1000000000 || ets.tv_nsec < 0) { + error = EINVAL; + goto bad; + } + for (;;) { + ts2 = ets; + getnanouptime(&ts); + timespecsub(&ts2, &ts); + if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) { + error = ETIMEDOUT; + break; + } + TIMESPEC_TO_TIMEVAL(&tv, &ts2); + error = _mqueue_send(mq, msg, tvtohz(&tv)); + if (error != ETIMEDOUT) + break; + } + if (error == 0) + return (0); +bad: + mqueue_freemsg(msg); + return (error); +} + +/* + * Common routine to send a message + */ +static int +_mqueue_send(struct mqueue *mq, struct mqueue_msg *msg, int timo) +{ + struct mqueue_msg *msg2; + int error = 0; + + mtx_lock(&mq->mq_mutex); + while (mq->mq_curmsgs >= mq->mq_maxmsg && error == 0) { + if (timo < 0) { + mtx_unlock(&mq->mq_mutex); + mqueue_freemsg(msg); + return (EAGAIN); + } + mq->mq_senders++; + error = msleep(&mq->mq_senders, &mq->mq_mutex, + PSOCK | PCATCH, "mqsend", timo); + mq->mq_senders--; + if (error == EAGAIN) + error = ETIMEDOUT; + } + if (mq->mq_curmsgs >= mq->mq_maxmsg) { + mtx_unlock(&mq->mq_mutex); + return (error); + } + error = 0; + if (TAILQ_EMPTY(&mq->mq_msgq)) { + TAILQ_INSERT_HEAD(&mq->mq_msgq, msg, msg_link); + } else { + if (msg->msg_prio <= TAILQ_LAST(&mq->mq_msgq, msgq)->msg_prio) { + TAILQ_INSERT_TAIL(&mq->mq_msgq, msg, msg_link); + } else { + TAILQ_FOREACH(msg2, &mq->mq_msgq, msg_link) { + if (msg2->msg_prio < msg->msg_prio) + break; + } + TAILQ_INSERT_BEFORE(msg2, msg, msg_link); + } + } + mq->mq_curmsgs++; + mq->mq_totalbytes += msg->msg_size; + if (mq->mq_receivers) + wakeup_one(&mq->mq_receivers); + else if (mq->mq_notifier != NULL) + mqueue_send_notification(mq); + if (mq->mq_flags & MQ_RSEL) { + mq->mq_flags &= ~MQ_RSEL; + selwakeuppri(&mq->mq_rsel, PSOCK); + } + KNOTE_LOCKED(&mq->mq_rsel.si_note, 0); + mtx_unlock(&mq->mq_mutex); + return (0); +} + +/* + * Send realtime a signal to process which registered itself + * successfully by mq_notify. + */ +static void +mqueue_send_notification(struct mqueue *mq) +{ + struct mqueue_user *mu; + + mtx_assert(&mq->mq_mutex, MA_OWNED); + mu = mq->mq_notifier; + PROC_LOCK(mu->mu_proc); + if (!KSI_ONQ(&mu->mu_ksi)) + psignal_event(mu->mu_proc, &mu->mu_sigev, &mu->mu_ksi); + PROC_UNLOCK(mu->mu_proc); + mq->mq_notifier = NULL; +} + +/* + * Get a message. if waitok is false, thread will not be + * blocked if there is no data in queue, otherwise, absolute + * time will be checked. + */ +int +mqueue_receive(struct mqueue *mq, char *msg_ptr, + size_t msg_len, unsigned *msg_prio, int waitok, + const struct timespec *abs_timeout) +{ + struct mqueue_msg *msg; + struct timespec ets, ts, ts2; + struct timeval tv; + int error; + + if (msg_len < mq->mq_msgsize) + return (EMSGSIZE); + + /* O_NONBLOCK case */ + if (!waitok) { + error = _mqueue_recv(mq, &msg, -1); + if (error) + return (error); + goto received; + } + + /* we allow a null timeout (wait forever). */ + if (abs_timeout == NULL) { + error = _mqueue_recv(mq, &msg, 0); + if (error) + return (error); + goto received; + } + + /* try to get a message before checking time */ + error = _mqueue_recv(mq, &msg, -1); + if (error == 0) + goto received; + + if (error != EAGAIN) + return (error); + + error = copyin(abs_timeout, &ets, sizeof(ets)); + if (error != 0) + return (error); + if (ets.tv_nsec >= 1000000000 || ets.tv_nsec < 0) { + error = EINVAL; + return (error); + } + + for (;;) { + ts2 = ets; + getnanouptime(&ts); + timespecsub(&ts2, &ts); + if (ts2.tv_sec < 0 || (ts2.tv_sec == 0 && ts2.tv_nsec <= 0)) { + error = ETIMEDOUT; + return (error); + } + TIMESPEC_TO_TIMEVAL(&tv, &ts2); + error = _mqueue_recv(mq, &msg, tvtohz(&tv)); + if (error == 0) + break; + if (error != ETIMEDOUT) + return (error); + } + +received: + error = mqueue_savemsg(msg, msg_ptr, msg_prio); + if (error == 0) { + curthread->td_retval[0] = msg->msg_size; + curthread->td_retval[1] = 0; + } + mqueue_freemsg(msg); + return (error); +} + +/* + * Common routine to receive a message + */ +static int +_mqueue_recv(struct mqueue *mq, struct mqueue_msg **msg, int timo) +{ + int error = 0; + + mtx_lock(&mq->mq_mutex); + while ((*msg = TAILQ_FIRST(&mq->mq_msgq)) == NULL && error == 0) { + if (timo < 0) { + mtx_unlock(&mq->mq_mutex); + return (EAGAIN); + } + mq->mq_receivers++; + error = msleep(&mq->mq_receivers, &mq->mq_mutex, + PSOCK | PCATCH, "mqrecv", timo); + mq->mq_receivers--; + if (error == EAGAIN) + error = ETIMEDOUT; + } + if (*msg != NULL) { + error = 0; + TAILQ_REMOVE(&mq->mq_msgq, *msg, msg_link); + mq->mq_curmsgs--; + mq->mq_totalbytes -= (*msg)->msg_size; + if (mq->mq_senders) + wakeup_one(&mq->mq_senders); + if (mq->mq_flags & MQ_WSEL) { + mq->mq_flags &= ~MQ_WSEL; + selwakeuppri(&mq->mq_wsel, PSOCK); + } + KNOTE_LOCKED(&mq->mq_wsel.si_note, 0); + } + if (mq->mq_notifier != NULL && mq->mq_receivers == 0 && + !TAILQ_EMPTY(&mq->mq_msgq)) { + mqueue_send_notification(mq); + } + mtx_unlock(&mq->mq_mutex); + return (error); +} + +static __inline struct mqueue_user * +mquser_alloc(void) +{ + return (uma_zalloc(mquser_zone, M_WAITOK | M_ZERO)); +} + +static __inline void +mquser_free(struct mqueue_user *p) +{ + uma_zfree(mquser_zone, p); +} + +/* + * Syscall to open a message queue + */ +int +mq_open(struct thread *td, struct mq_open_args *uap) +{ + char path[MQFS_NAMELEN+1]; + struct mq_attr attr, *pattr; + struct mqfs_node *pn; + struct filedesc *fdp; + struct file *fp; + struct mqueue_user *mu; + struct mqueue *mq; + int fd, error, len, flags, cmode; + + if ((uap->flags & O_ACCMODE) == O_ACCMODE) + return (EINVAL); + + fdp = td->td_proc->p_fd; + flags = FFLAGS(uap->flags); + cmode = (((uap->mode & ~fdp->fd_cmask) & ALLPERMS) & ~S_ISTXT); + if ((flags & O_CREAT) && (uap->attr != NULL)) { + error = copyin(uap->attr, &attr, sizeof(attr)); + if (error) + return (error); + if (attr.mq_maxmsg <= 0 || attr.mq_maxmsg > maxmsg) + return (EINVAL); + if (attr.mq_msgsize <= 0 || attr.mq_msgsize > maxmsgsize) + return (EINVAL); + pattr = &attr; + } else + pattr = NULL; + + error = copyinstr(uap->path, path, MQFS_NAMELEN + 1, NULL); + if (error) + return (error); + + /* + * The first character of name must be a slash (/) character + * and the remaining characters of name cannot include any slash + * characters. + */ + len = strlen(path); + if (len < 2 || path[0] != '/' || index(path + 1, '/') != NULL) + return (EINVAL); + + fdp = td->td_proc->p_fd; + error = falloc(td, &fp, &fd); + if (error) + return (error); + + sx_xlock(&mqfs_data.mi_lock); + pn = mqfs_search(mqfs_data.mi_root, path + 1, len - 1); + if (pn == NULL) { + if (!(flags & O_CREAT)) { + error = ENOENT; + } else { + mq = mqueue_alloc(pattr); + if (mq != NULL) + pn = mqfs_create_file(mqfs_data.mi_root, + path + 1, len - 1); + if (pn == NULL) { + if (mq != NULL) + mqueue_free(mq); + error = ENOSPC; + } + } + + if (error == 0) { + pn->mn_data = mq; + getnanotime(&pn->mn_birth); + pn->mn_ctime = pn->mn_atime = pn->mn_mtime + = pn->mn_birth; + pn->mn_uid = td->td_ucred->cr_uid; + pn->mn_gid = td->td_ucred->cr_gid; + pn->mn_mode = cmode; + } + } else { + if ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) { + error = EEXIST; + } else { + int acc_mode = 0; + + if (flags & FREAD) + acc_mode |= VREAD; + if (flags & FWRITE) + acc_mode |= VWRITE; + error = vaccess(VREG, pn->mn_mode, pn->mn_uid, + pn->mn_gid, acc_mode, td->td_ucred, NULL); + } + } + + if (error) { + sx_xunlock(&mqfs_data.mi_lock); + fdclose(fdp, fp, fd, td); + fdrop(fp, td); + return (error); + } + + mqnode_addref(pn); + sx_xunlock(&mqfs_data.mi_lock); + + mu = mquser_alloc(); + mu->mu_node = pn; + ksiginfo_init(&mu->mu_ksi); + mu->mu_ksi.ksi_flags |= KSI_INS | KSI_EXT; + mu->mu_ksi.ksi_code = SI_MESGQ; + mu->mu_proc = td->td_proc; + FILE_LOCK(fp); + fp->f_flag = (flags & (FREAD | FWRITE | O_NONBLOCK)); + fp->f_type = DTYPE_MQUEUE; + fp->f_ops = &mqueueops; + fp->f_data = mu; + FILE_UNLOCK(fp); + + FILEDESC_LOCK_FAST(fdp); + if (fdp->fd_ofiles[fd] == fp) + fdp->fd_ofileflags[fd] |= UF_EXCLOSE; + FILEDESC_UNLOCK_FAST(fdp); + td->td_retval[0] = fd; + fdrop(fp, td); + return (0); +} + +/* + * Syscall to unlink a message queue + */ +int +mq_unlink(struct thread *td, struct mq_unlink_args *uap) +{ + char path[MQFS_NAMELEN+1]; + struct mqfs_node *pn; + int error, len; + + error = copyinstr(uap->path, path, MQFS_NAMELEN + 1, NULL); + if (error) + return (error); + + len = strlen(path); + if (len < 2 || path[0] != '/' || index(path + 1, '/') != NULL) + return (EINVAL); + + sx_xlock(&mqfs_data.mi_lock); + pn = mqfs_search(mqfs_data.mi_root, path + 1, len - 1); + if (pn != NULL) + error = do_unlink(pn, td->td_ucred); + else + error = ENOENT; + sx_xunlock(&mqfs_data.mi_lock); + return (error); +} + +typedef int (*_fgetf)(struct thread *, int, struct file **); + +/* + * Get message queue by giving file slot + */ +static int +_getmq(struct thread *td, int fd, _fgetf func, + struct file **fpp, struct mqfs_node **ppn, struct mqueue **pmq) +{ + struct mqueue_user *mu; + struct mqfs_node *pn; + int error; + + error = func(td, fd, fpp); + if (error) + return (error); + if (&mqueueops != (*fpp)->f_ops) { + fdrop(*fpp, td); + return (EBADF); + } + mu = (*fpp)->f_data; + pn = mu->mu_node; + if (ppn) + *ppn = pn; + if (pmq) + *pmq = pn->mn_data; + return (0); +} + +static __inline int +getmq(struct thread *td, int fd, struct file **fpp, struct mqfs_node **ppn, + struct mqueue **pmq) +{ + return _getmq(td, fd, fget, fpp, ppn, pmq); +} + +static __inline int +getmq_read(struct thread *td, int fd, struct file **fpp, + struct mqfs_node **ppn, struct mqueue **pmq) +{ + return _getmq(td, fd, fget_read, fpp, ppn, pmq); +} + +static __inline int +getmq_write(struct thread *td, int fd, struct file **fpp, + struct mqfs_node **ppn, struct mqueue **pmq) +{ + return _getmq(td, fd, fget_write, fpp, ppn, pmq); +} + +/* + * Syscall + */ +int +mq_setattr(struct thread *td, struct mq_setattr_args *uap) +{ + struct mqueue *mq; + struct file *fp; + struct mq_attr attr, oattr; + int error; + + if (uap->attr) { + error = copyin(uap->attr, &attr, sizeof(attr)); + if (error) + return (error); + if (attr.mq_flags & ~O_NONBLOCK) + return (EINVAL); + } + error = getmq(td, uap->mqd, &fp, NULL, &mq); + if (error) + return (error); + oattr.mq_maxmsg = mq->mq_maxmsg; + oattr.mq_msgsize = mq->mq_msgsize; + oattr.mq_curmsgs = mq->mq_curmsgs; + FILE_LOCK(fp); + oattr.mq_flags = (O_NONBLOCK & fp->f_flag); + if (uap->attr) { + fp->f_flag &= ~O_NONBLOCK; + fp->f_flag |= (attr.mq_flags & O_NONBLOCK); + } + FILE_UNLOCK(fp); + fdrop(fp, td); + if (uap->oattr) + error = copyout(&oattr, uap->oattr, sizeof(oattr)); + return (error); +} + +/* + * Syscall + */ +int +mq_timedreceive(struct thread *td, struct mq_timedreceive_args *uap) +{ + struct mqueue *mq; + struct file *fp; + int error; + int waitok; + + error = getmq_read(td, uap->mqd, &fp, NULL, &mq); + if (error) + return (error); + waitok = !(fp->f_flag & O_NONBLOCK); + error = mqueue_receive(mq, uap->msg_ptr, uap->msg_len, + uap->msg_prio, waitok, uap->abs_timeout); + fdrop(fp, td); + return (error); +} + +/* + * Syscall + */ +int +mq_timedsend(struct thread *td, struct mq_timedsend_args *uap) +{ + struct mqueue *mq; + struct file *fp; + int error, waitok; + + error = getmq_write(td, uap->mqd, &fp, NULL, &mq); + if (error) + return (error); + waitok = !(fp->f_flag & O_NONBLOCK); + error = mqueue_send(mq, uap->msg_ptr, uap->msg_len, + uap->msg_prio, waitok, uap->abs_timeout); + fdrop(fp, td); + return (error); +} + +/* + * Syscall + */ +int +mq_notify(struct thread *td, struct mq_notify_args *uap) +{ + struct sigevent ev; + struct mqueue_user *mu; + struct mqueue *mq; + struct file *fp; + int error; + + if (uap->sigev) { + error = copyin(uap->sigev, &ev, sizeof(ev)); + if (error) + return (error); + if (ev.sigev_notify != SIGEV_SIGNAL && + ev.sigev_notify != SIGEV_THREAD_ID) + return (EINVAL); + if ((ev.sigev_notify == SIGEV_SIGNAL || + ev.sigev_notify == SIGEV_THREAD_ID) && + !_SIG_VALID(ev.sigev_signo)) + return (EINVAL); + } + error = getmq(td, uap->mqd, &fp, NULL, &mq); + if (error) + return (error); + mu = fp->f_data; + mtx_lock(&mq->mq_mutex); + if (uap->sigev != NULL) { + if (mq->mq_notifier != NULL) { + error = EBUSY; + } else { + PROC_LOCK(td->td_proc); + sigqueue_take(&mu->mu_ksi); + PROC_UNLOCK(td->td_proc); + mq->mq_notifier = mu; + mu->mu_sigev = ev; + /* + * if there is no receivers and message queue is not + * empty, we should send notification as soon as + * possible. + */ + if (mq->mq_receivers == 0 && + !TAILQ_EMPTY(&mq->mq_msgq)) + mqueue_send_notification(mq); + } + } else { + if (mq->mq_notifier == mu) + mq->mq_notifier = NULL; + else + error = EPERM; + } + mtx_unlock(&mq->mq_mutex); + fdrop(fp, td); + return (error); +} + +static int +mqf_read(struct file *fp, struct uio *uio, struct ucred *active_cred, + int flags, struct thread *td) +{ + return (EOPNOTSUPP); +} + +static int +mqf_write(struct file *fp, struct uio *uio, struct ucred *active_cred, + int flags, struct thread *td) +{ + return (EOPNOTSUPP); +} + +static int +mqf_ioctl(struct file *fp, u_long cmd, void *data, + struct ucred *active_cred, struct thread *td) +{ + return (ENOTTY); +} + +static int +mqf_poll(struct file *fp, int events, struct ucred *active_cred, + struct thread *td) +{ + struct mqueue *mq = FPTOMQ(fp); + int revents = 0; + + mtx_lock(&mq->mq_mutex); + if (events & (POLLIN | POLLRDNORM)) { + if (mq->mq_curmsgs) { + revents |= events & (POLLIN | POLLRDNORM); + } else { + mq->mq_flags |= MQ_RSEL; + selrecord(td, &mq->mq_rsel); + } + } + if (events & POLLOUT) { + if (mq->mq_curmsgs < mq->mq_maxmsg) + revents |= POLLOUT; + else { + mq->mq_flags |= MQ_WSEL; + selrecord(td, &mq->mq_wsel); + } + } + mtx_unlock(&mq->mq_mutex); + return (revents); +} + +static int +mqf_close(struct file *fp, struct thread *td) +{ + struct mqueue_user *mu; + struct mqfs_node *pn; + struct mqueue *mq; + + FILE_LOCK(fp); + fp->f_ops = &badfileops; + FILE_UNLOCK(fp); + mu = fp->f_data; + fp->f_data = NULL; + pn = mu->mu_node; + mq = pn->mn_data; + mtx_lock(&mq->mq_mutex); + if (mq->mq_notifier == mu) { + PROC_LOCK(td->td_proc); + sigqueue_take(&mu->mu_ksi); + PROC_UNLOCK(td->td_proc); + mq->mq_notifier = NULL; + } + /* have to wakeup thread in same process */ + if (mq->mq_flags & MQ_RSEL) { + mq->mq_flags &= ~MQ_RSEL; + selwakeuppri(&mq->mq_rsel, PSOCK); + } + if (mq->mq_flags & MQ_WSEL) { + mq->mq_flags &= ~MQ_WSEL; + selwakeuppri(&mq->mq_wsel, PSOCK); + } + mtx_unlock(&mq->mq_mutex); + sx_xlock(&mqfs_data.mi_lock); + mqnode_release(pn); + sx_xunlock(&mqfs_data.mi_lock); + mquser_free(mu); + return (0); +} + +static int +mqf_stat(struct file *fp, struct stat *st, struct ucred *active_cred, + struct thread *td) +{ + struct mqueue_user *mu = fp->f_data; + struct mqfs_node *pn = mu->mu_node; + + bzero(st, sizeof *st); + st->st_atimespec = pn->mn_atime; + st->st_mtimespec = pn->mn_mtime; + st->st_ctimespec = pn->mn_ctime; + st->st_birthtimespec = pn->mn_birth; + st->st_uid = pn->mn_uid; + st->st_gid = pn->mn_gid; + st->st_mode = S_IFIFO | pn->mn_mode; + return (0); +} + +static int +mqf_kqfilter(struct file *fp, struct knote *kn) +{ + struct mqueue *mq = FPTOMQ(fp); + int error = 0; + + if (kn->kn_filter == EVFILT_READ) { + kn->kn_fop = &mq_rfiltops; + knlist_add(&mq->mq_rsel.si_note, kn, 0); + } else if (kn->kn_filter == EVFILT_WRITE) { + kn->kn_fop = &mq_wfiltops; + knlist_add(&mq->mq_wsel.si_note, kn, 0); + } else + error = EINVAL; + return (error); +} + +static void +filt_mqdetach(struct knote *kn) +{ + struct mqueue *mq = FPTOMQ(kn->kn_fp); + + if (kn->kn_filter == EVFILT_READ) + knlist_remove(&mq->mq_rsel.si_note, kn, 0); + else if (kn->kn_filter == EVFILT_WRITE) + knlist_remove(&mq->mq_wsel.si_note, kn, 0); + else + panic("filt_mqdetach"); +} + +static int +filt_mqread(struct knote *kn, long hint) +{ + struct mqueue *mq = FPTOMQ(kn->kn_fp); + + mtx_assert(&mq->mq_mutex, MA_OWNED); + return (mq->mq_curmsgs != 0); +} + +static int +filt_mqwrite(struct knote *kn, long hint) +{ + struct mqueue *mq = FPTOMQ(kn->kn_fp); + + mtx_assert(&mq->mq_mutex, MA_OWNED); + return (mq->mq_curmsgs < mq->mq_maxmsg); +} + +static struct fileops mqueueops = { + .fo_read = mqf_read, + .fo_write = mqf_write, + .fo_ioctl = mqf_ioctl, + .fo_poll = mqf_poll, + .fo_kqfilter = mqf_kqfilter, + .fo_stat = mqf_stat, + .fo_close = mqf_close +}; + +static struct vop_vector mqfs_vnodeops = { + .vop_default = &default_vnodeops, + .vop_access = mqfs_access, + .vop_cachedlookup = mqfs_lookup, + .vop_lookup = vfs_cache_lookup, + .vop_reclaim = mqfs_reclaim, + .vop_create = mqfs_create, + .vop_remove = mqfs_remove, + .vop_inactive = mqfs_inactive, + .vop_open = mqfs_open, + .vop_close = mqfs_close, + .vop_getattr = mqfs_getattr, + .vop_setattr = mqfs_setattr, + .vop_read = mqfs_read, + .vop_write = VOP_EOPNOTSUPP, + .vop_readdir = mqfs_readdir, + .vop_mkdir = VOP_EOPNOTSUPP, + .vop_rmdir = VOP_EOPNOTSUPP +}; + +static struct vfsops mqfs_vfsops = { + .vfs_init = mqfs_init, + .vfs_uninit = mqfs_uninit, + .vfs_mount = mqfs_mount, + .vfs_unmount = mqfs_unmount, + .vfs_root = mqfs_root, + .vfs_statfs = mqfs_statfs, +}; + +SYSCALL_MODULE_HELPER(mq_open); +SYSCALL_MODULE_HELPER(mq_setattr); +SYSCALL_MODULE_HELPER(mq_timedsend); +SYSCALL_MODULE_HELPER(mq_timedreceive); +SYSCALL_MODULE_HELPER(mq_notify); +SYSCALL_MODULE_HELPER(mq_unlink); + +VFS_SET(mqfs_vfsops, mqueue, VFCF_SYNTHETIC); +MODULE_VERSION(mqueue, 1); |