X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=kernel%2Fvserver%2Fcontext.c;h=55a706219d033a92cacdfd12c472b85bc2eca4b0;hb=34a75f0025b9cf803b6a88db032e6ad6950c9313;hp=3d23d7142e4fd90748f9f5256226832ac3d35706;hpb=af20d436230b2df6d73a406b6f1b31ae000775cb;p=linux-2.6.git diff --git a/kernel/vserver/context.c b/kernel/vserver/context.c index 3d23d7142..55a706219 100644 --- a/kernel/vserver/context.c +++ b/kernel/vserver/context.c @@ -19,7 +19,6 @@ * */ -#include #include #include #include @@ -29,8 +28,10 @@ #include #include #include +#include #include +#include #include #include @@ -59,14 +60,16 @@ static struct vx_info *__alloc_vx_info(xid_t xid) memset (new, 0, sizeof(struct vx_info)); new->vx_id = xid; - // INIT_RCU_HEAD(&new->vx_rcu); INIT_HLIST_NODE(&new->vx_hlist); atomic_set(&new->vx_usecnt, 0); atomic_set(&new->vx_tasks, 0); new->vx_parent = NULL; new->vx_state = 0; - new->vx_lock = SPIN_LOCK_UNLOCKED; - init_waitqueue_head(&new->vx_exit); + init_waitqueue_head(&new->vx_wait); + + /* prepare reaper */ + get_task_struct(child_reaper); + new->vx_reaper = child_reaper; /* rest of init goes here */ vx_info_init_limit(&new->limit); @@ -74,11 +77,13 @@ static struct vx_info *__alloc_vx_info(xid_t xid) vx_info_init_cvirt(&new->cvirt); vx_info_init_cacct(&new->cacct); - - new->vx_flags = VXF_STATE_SETUP|VXF_STATE_INIT; + new->vx_flags = VXF_INIT_SET; new->vx_bcaps = CAP_INIT_EFF_SET; new->vx_ccaps = 0; + new->reboot_cmd = 0; + new->exit_code = 0; + vxdprintk(VXD_CBIT(xid, 0), "alloc_vx_info(%d) = %p", xid, new); vxh_alloc_vx_info(new); @@ -107,14 +112,15 @@ static void __dealloc_vx_info(struct vx_info *vxi) kfree(vxi); } -void __shutdown_vx_info(struct vx_info *vxi) +static void __shutdown_vx_info(struct vx_info *vxi) { struct namespace *namespace; struct fs_struct *fs; might_sleep(); - vs_context_state(vxi, VS_CONTEXT_DESTROY); + vxi->vx_state |= VXS_SHUTDOWN; + vs_state_change(vxi, VSC_SHUTDOWN); namespace = xchg(&vxi->vx_namespace, NULL); if (namespace) @@ -130,13 +136,12 @@ void __shutdown_vx_info(struct vx_info *vxi) void free_vx_info(struct vx_info *vxi) { /* context shutdown is mandatory */ - // BUG_ON(vxi->vx_state != VXS_SHUTDOWN); + BUG_ON(!vx_info_state(vxi, VXS_SHUTDOWN)); BUG_ON(atomic_read(&vxi->vx_usecnt)); BUG_ON(atomic_read(&vxi->vx_tasks)); BUG_ON(vx_info_state(vxi, VXS_HASHED)); - // BUG_ON(!vx_state(vxi, VXS_DEFUNCT)); BUG_ON(vxi->vx_namespace); BUG_ON(vxi->vx_fs); @@ -176,9 +181,8 @@ static inline void __hash_vx_info(struct vx_info *vxi) vxh_hash_vx_info(vxi); /* context must not be hashed */ - BUG_ON(vxi->vx_state & VXS_HASHED); + BUG_ON(vx_info_state(vxi, VXS_HASHED)); - get_vx_info(vxi); vxi->vx_state |= VXS_HASHED; head = &vx_info_hash[__hashval(vxi->vx_id)]; hlist_add_head(&vxi->vx_hlist, head); @@ -196,13 +200,11 @@ static inline void __unhash_vx_info(struct vx_info *vxi) "__unhash_vx_info: %p[#%d]", vxi, vxi->vx_id); vxh_unhash_vx_info(vxi); - /* maybe warn on that? */ - if (!(vxi->vx_state & VXS_HASHED)) - return; + /* context must be hashed */ + BUG_ON(!vx_info_state(vxi, VXS_HASHED)); vxi->vx_state &= ~VXS_HASHED; hlist_del(&vxi->vx_hlist); - put_vx_info(vxi); } @@ -229,7 +231,7 @@ found: vxdprintk(VXD_CBIT(xid, 0), "__lookup_vx_info(#%u): %p[#%u]", xid, vxi, vxi?vxi->vx_id:0); - vxh_lookup_vx_info(xid, vxi); + vxh_lookup_vx_info(vxi, xid); return vxi; } @@ -313,7 +315,7 @@ static struct vx_info * __loc_vx_info(int id, int *err) out_unlock: spin_unlock(&vx_info_hash_lock); - vxh_loc_vx_info(id, vxi); + vxh_loc_vx_info(vxi, id); if (new) __dealloc_vx_info(new); return vxi; @@ -324,7 +326,7 @@ out_unlock: /* __create_vx_info() * create the requested context - * get() it and hash it */ + * get() and hash it */ static struct vx_info * __create_vx_info(int id) { @@ -332,9 +334,8 @@ static struct vx_info * __create_vx_info(int id) vxdprintk(VXD_CBIT(xid, 1), "create_vx_info(%d)*", id); - if (!(new = __alloc_vx_info(id))) { + if (!(new = __alloc_vx_info(id))) return ERR_PTR(-ENOMEM); - } /* required to make dynamic xids unique */ spin_lock(&vx_info_hash_lock); @@ -349,7 +350,7 @@ static struct vx_info * __create_vx_info(int id) } new->vx_id = id; } - /* existing context requested */ + /* static context requested */ else if ((vxi = __lookup_vx_info(id))) { vxdprintk(VXD_CBIT(xid, 0), "create_vx_info(%d) = %p (already there)", id, vxi); @@ -367,7 +368,7 @@ static struct vx_info * __create_vx_info(int id) goto out_unlock; } - /* new context requested */ + /* new context */ vxdprintk(VXD_CBIT(xid, 0), "create_vx_info(%d) = %p (new)", id, new); __hash_vx_info(get_vx_info(new)); @@ -375,7 +376,7 @@ static struct vx_info * __create_vx_info(int id) out_unlock: spin_unlock(&vx_info_hash_lock); - vxh_create_vx_info(id, IS_ERR(vxi)?NULL:vxi); + vxh_create_vx_info(IS_ERR(vxi)?NULL:vxi, id); if (new) __dealloc_vx_info(new); return vxi; @@ -391,15 +392,16 @@ void unhash_vx_info(struct vx_info *vxi) spin_lock(&vx_info_hash_lock); __unhash_vx_info(vxi); spin_unlock(&vx_info_hash_lock); + __wakeup_vx_info(vxi); } -/* locate_vx_info() +/* lookup_vx_info() * search for a vx_info and get() it * negative id means current */ -struct vx_info *locate_vx_info(int id) +struct vx_info *lookup_vx_info(int id) { struct vx_info *vxi = NULL; @@ -429,7 +431,7 @@ int xid_is_hashed(xid_t xid) #ifdef CONFIG_VSERVER_LEGACY -struct vx_info *locate_or_create_vx_info(int id) +struct vx_info *lookup_or_create_vx_info(int id) { int err; @@ -470,6 +472,7 @@ out: } #endif + int vx_migrate_user(struct task_struct *p, struct vx_info *vxi) { struct user_struct *new_user, *old_user; @@ -490,10 +493,8 @@ int vx_migrate_user(struct task_struct *p, struct vx_info *vxi) return 0; } -void vx_mask_bcaps(struct task_struct *p) +void vx_mask_bcaps(struct vx_info *vxi, struct task_struct *p) { - struct vx_info *vxi = p->vx_info; - p->cap_effective &= vxi->vx_bcaps; p->cap_inheritable &= vxi->vx_bcaps; p->cap_permitted &= vxi->vx_bcaps; @@ -505,12 +506,15 @@ void vx_mask_bcaps(struct task_struct *p) static int vx_openfd_task(struct task_struct *tsk) { struct files_struct *files = tsk->files; + struct fdtable *fdt; const unsigned long *bptr; int count, total; + /* no rcu_read_lock() because of spin_lock() */ spin_lock(&files->file_lock); - bptr = files->open_fds->fds_bits; - count = files->max_fds / (sizeof(unsigned long) * 8); + fdt = files_fdtable(files); + bptr = fdt->open_fds->fds_bits; + count = fdt->max_fds / (sizeof(unsigned long) * 8); for (total = 0; count > 0; count--) { if (*bptr) total += hweight_long(*bptr); @@ -572,7 +576,7 @@ int vx_migrate_task(struct task_struct *p, struct vx_info *vxi) "moved task %p into vxi:%p[#%d]", p, vxi, vxi->vx_id); - vx_mask_bcaps(p); + vx_mask_bcaps(vxi, p); task_unlock(p); } out: @@ -580,21 +584,98 @@ out: return ret; } +int vx_set_reaper(struct vx_info *vxi, struct task_struct *p) +{ + struct task_struct *old_reaper; + + if (!vxi) + return -EINVAL; + + vxdprintk(VXD_CBIT(xid, 6), + "vx_set_reaper(%p[#%d],%p[#%d,%d])", + vxi, vxi->vx_id, p, p->xid, p->pid); + + old_reaper = vxi->vx_reaper; + if (old_reaper == p) + return 0; + + /* set new child reaper */ + get_task_struct(p); + vxi->vx_reaper = p; + put_task_struct(old_reaper); + return 0; +} + int vx_set_init(struct vx_info *vxi, struct task_struct *p) { if (!vxi) return -EINVAL; - if (vxi->vx_initpid) - return -EPERM; vxdprintk(VXD_CBIT(xid, 6), "vx_set_init(%p[#%d],%p[#%d,%d,%d])", vxi, vxi->vx_id, p, p->xid, p->pid, p->tgid); + vxi->vx_flags &= ~VXF_STATE_INIT; vxi->vx_initpid = p->tgid; return 0; } +void vx_exit_init(struct vx_info *vxi, struct task_struct *p, int code) +{ + vxdprintk(VXD_CBIT(xid, 6), + "vx_exit_init(%p[#%d],%p[#%d,%d,%d])", + vxi, vxi->vx_id, p, p->xid, p->pid, p->tgid); + + vxi->exit_code = code; + vxi->vx_initpid = 0; +} + +void vx_set_persistent(struct vx_info *vxi) +{ + vxdprintk(VXD_CBIT(xid, 6), + "vx_set_persistent(%p[#%d])", vxi, vxi->vx_id); + + get_vx_info(vxi); + claim_vx_info(vxi, current); +} + +void vx_clear_persistent(struct vx_info *vxi) +{ + vxdprintk(VXD_CBIT(xid, 6), + "vx_clear_persistent(%p[#%d])", vxi, vxi->vx_id); + + release_vx_info(vxi, current); + put_vx_info(vxi); +} + +void vx_update_persistent(struct vx_info *vxi) +{ + if (vx_info_flags(vxi, VXF_PERSISTENT, 0)) + vx_set_persistent(vxi); + else + vx_clear_persistent(vxi); +} + + +/* task must be current or locked */ + +void exit_vx_info(struct task_struct *p, int code) +{ + struct vx_info *vxi = p->vx_info; + + if (vxi) { + atomic_dec(&vxi->cvirt.nr_threads); + vx_nproc_dec(p); + + vxi->exit_code = code; + if (vxi->vx_initpid == p->tgid) + vx_exit_init(vxi, p, code); + if (vxi->vx_reaper == p) + vx_set_reaper(vxi, child_reaper); + release_vx_info(vxi, p); + } +} + /* vserver syscall commands below here */ @@ -634,7 +715,7 @@ int vc_vx_info(uint32_t id, void __user *data) if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RESOURCE)) return -EPERM; - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH; @@ -652,15 +733,17 @@ int vc_vx_info(uint32_t id, void __user *data) int vc_ctx_create(uint32_t xid, void __user *data) { + struct vcmd_ctx_create vc_data = { .flagword = VXF_INIT_SET }; struct vx_info *new_vxi; int ret; if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (data && copy_from_user (&vc_data, data, sizeof(vc_data))) + return -EFAULT; if ((xid > MAX_S_CONTEXT) && (xid != VX_DYNAMIC_ID)) return -EINVAL; - if (xid < 2) return -EINVAL; @@ -668,10 +751,29 @@ int vc_ctx_create(uint32_t xid, void __user *data) if (IS_ERR(new_vxi)) return PTR_ERR(new_vxi); - vs_context_state(new_vxi, VS_CONTEXT_CREATED); - ret = new_vxi->vx_id; - vx_migrate_task(current, new_vxi); - /* if this fails, we might end up with a hashed vx_info */ + /* initial flags */ + new_vxi->vx_flags = vc_data.flagword; + + /* get a reference for persistent contexts */ + if ((vc_data.flagword & VXF_PERSISTENT)) + vx_set_persistent(new_vxi); + + ret = -ENOEXEC; + if (vs_state_change(new_vxi, VSC_STARTUP)) + goto out_unhash; + ret = vx_migrate_task(current, new_vxi); + if (!ret) { + /* return context id on success */ + ret = new_vxi->vx_id; + goto out; + } +out_unhash: + /* prepare for context disposal */ + new_vxi->vx_state |= VXS_SHUTDOWN; + if ((vc_data.flagword & VXF_PERSISTENT)) + vx_clear_persistent(new_vxi); + __unhash_vx_info(new_vxi); +out: put_vx_info(new_vxi); return ret; } @@ -679,10 +781,13 @@ int vc_ctx_create(uint32_t xid, void __user *data) int vc_ctx_migrate(uint32_t id, void __user *data) { + struct vcmd_ctx_migrate vc_data = { .flagword = 0 }; struct vx_info *vxi; if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (data && copy_from_user (&vc_data, data, sizeof(vc_data))) + return -EFAULT; /* dirty hack until Spectator becomes a cap */ if (id == 1) { @@ -690,10 +795,14 @@ int vc_ctx_migrate(uint32_t id, void __user *data) return 0; } - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH; vx_migrate_task(current, vxi); + if (vc_data.flagword & VXM_SET_INIT) + vx_set_init(vxi, current); + if (vc_data.flagword & VXM_SET_REAPER) + vx_set_reaper(vxi, current); put_vx_info(vxi); return 0; } @@ -707,7 +816,7 @@ int vc_get_cflags(uint32_t id, void __user *data) if (!capable(CAP_SYS_ADMIN)) return -EPERM; - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH; @@ -734,7 +843,7 @@ int vc_set_cflags(uint32_t id, void __user *data) if (copy_from_user (&vc_data, data, sizeof(vc_data))) return -EFAULT; - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH; @@ -742,14 +851,20 @@ int vc_set_cflags(uint32_t id, void __user *data) mask = vx_mask_mask(vc_data.mask, vxi->vx_flags, VXF_ONE_TIME); trigger = (mask & vxi->vx_flags) ^ (mask & vc_data.flagword); - if (trigger & VXF_STATE_SETUP) - vx_mask_bcaps(current); - if (trigger & VXF_STATE_INIT) - if (vxi == current->vx_info) + if (vxi == current->vx_info) { + if (trigger & VXF_STATE_SETUP) + vx_mask_bcaps(vxi, current); + if (trigger & VXF_STATE_INIT) { vx_set_init(vxi, current); + vx_set_reaper(vxi, current); + } + } vxi->vx_flags = vx_mask_flags(vxi->vx_flags, vc_data.flagword, mask); + if (trigger & VXF_PERSISTENT) + vx_update_persistent(vxi); + put_vx_info(vxi); return 0; } @@ -762,7 +877,7 @@ int vc_get_ccaps(uint32_t id, void __user *data) if (!capable(CAP_SYS_ADMIN)) return -EPERM; - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH; @@ -786,7 +901,7 @@ int vc_set_ccaps(uint32_t id, void __user *data) if (copy_from_user (&vc_data, data, sizeof(vc_data))) return -EFAULT; - vxi = locate_vx_info(id); + vxi = lookup_vx_info(id); if (!vxi) return -ESRCH;