diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/cgroup.c | 248 | ||||
-rw-r--r-- | kernel/elfcore.c | 10 | ||||
-rw-r--r-- | kernel/pid_namespace.c | 8 | ||||
-rw-r--r-- | kernel/signal.c | 2 |
4 files changed, 12 insertions, 256 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 8bd9cfdc70d7..e0839bcd48c8 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c | |||
@@ -125,38 +125,6 @@ struct cfent { | |||
125 | }; | 125 | }; |
126 | 126 | ||
127 | /* | 127 | /* |
128 | * CSS ID -- ID per subsys's Cgroup Subsys State(CSS). used only when | ||
129 | * cgroup_subsys->use_id != 0. | ||
130 | */ | ||
131 | #define CSS_ID_MAX (65535) | ||
132 | struct css_id { | ||
133 | /* | ||
134 | * The css to which this ID points. This pointer is set to valid value | ||
135 | * after cgroup is populated. If cgroup is removed, this will be NULL. | ||
136 | * This pointer is expected to be RCU-safe because destroy() | ||
137 | * is called after synchronize_rcu(). But for safe use, css_tryget() | ||
138 | * should be used for avoiding race. | ||
139 | */ | ||
140 | struct cgroup_subsys_state __rcu *css; | ||
141 | /* | ||
142 | * ID of this css. | ||
143 | */ | ||
144 | unsigned short id; | ||
145 | /* | ||
146 | * Depth in hierarchy which this ID belongs to. | ||
147 | */ | ||
148 | unsigned short depth; | ||
149 | /* | ||
150 | * ID is freed by RCU. (and lookup routine is RCU safe.) | ||
151 | */ | ||
152 | struct rcu_head rcu_head; | ||
153 | /* | ||
154 | * Hierarchy of CSS ID belongs to. | ||
155 | */ | ||
156 | unsigned short stack[0]; /* Array of Length (depth+1) */ | ||
157 | }; | ||
158 | |||
159 | /* | ||
160 | * cgroup_event represents events which userspace want to receive. | 128 | * cgroup_event represents events which userspace want to receive. |
161 | */ | 129 | */ |
162 | struct cgroup_event { | 130 | struct cgroup_event { |
@@ -387,9 +355,6 @@ struct cgrp_cset_link { | |||
387 | static struct css_set init_css_set; | 355 | static struct css_set init_css_set; |
388 | static struct cgrp_cset_link init_cgrp_cset_link; | 356 | static struct cgrp_cset_link init_cgrp_cset_link; |
389 | 357 | ||
390 | static int cgroup_init_idr(struct cgroup_subsys *ss, | ||
391 | struct cgroup_subsys_state *css); | ||
392 | |||
393 | /* | 358 | /* |
394 | * css_set_lock protects the list of css_set objects, and the chain of | 359 | * css_set_lock protects the list of css_set objects, and the chain of |
395 | * tasks off each css_set. Nests outside task->alloc_lock due to | 360 | * tasks off each css_set. Nests outside task->alloc_lock due to |
@@ -841,8 +806,6 @@ static struct backing_dev_info cgroup_backing_dev_info = { | |||
841 | .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, | 806 | .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, |
842 | }; | 807 | }; |
843 | 808 | ||
844 | static int alloc_css_id(struct cgroup_subsys_state *child_css); | ||
845 | |||
846 | static struct inode *cgroup_new_inode(umode_t mode, struct super_block *sb) | 809 | static struct inode *cgroup_new_inode(umode_t mode, struct super_block *sb) |
847 | { | 810 | { |
848 | struct inode *inode = new_inode(sb); | 811 | struct inode *inode = new_inode(sb); |
@@ -4240,21 +4203,6 @@ static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask) | |||
4240 | goto err; | 4203 | goto err; |
4241 | } | 4204 | } |
4242 | } | 4205 | } |
4243 | |||
4244 | /* This cgroup is ready now */ | ||
4245 | for_each_root_subsys(cgrp->root, ss) { | ||
4246 | struct cgroup_subsys_state *css = cgroup_css(cgrp, ss); | ||
4247 | struct css_id *id = rcu_dereference_protected(css->id, true); | ||
4248 | |||
4249 | /* | ||
4250 | * Update id->css pointer and make this css visible from | ||
4251 | * CSS ID functions. This pointer will be dereferened | ||
4252 | * from RCU-read-side without locks. | ||
4253 | */ | ||
4254 | if (id) | ||
4255 | rcu_assign_pointer(id->css, css); | ||
4256 | } | ||
4257 | |||
4258 | return 0; | 4206 | return 0; |
4259 | err: | 4207 | err: |
4260 | cgroup_clear_dir(cgrp, subsys_mask); | 4208 | cgroup_clear_dir(cgrp, subsys_mask); |
@@ -4323,7 +4271,6 @@ static void init_css(struct cgroup_subsys_state *css, struct cgroup_subsys *ss, | |||
4323 | css->cgroup = cgrp; | 4271 | css->cgroup = cgrp; |
4324 | css->ss = ss; | 4272 | css->ss = ss; |
4325 | css->flags = 0; | 4273 | css->flags = 0; |
4326 | css->id = NULL; | ||
4327 | 4274 | ||
4328 | if (cgrp->parent) | 4275 | if (cgrp->parent) |
4329 | css->parent = cgroup_css(cgrp->parent, ss); | 4276 | css->parent = cgroup_css(cgrp->parent, ss); |
@@ -4455,12 +4402,6 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry, | |||
4455 | goto err_free_all; | 4402 | goto err_free_all; |
4456 | 4403 | ||
4457 | init_css(css, ss, cgrp); | 4404 | init_css(css, ss, cgrp); |
4458 | |||
4459 | if (ss->use_id) { | ||
4460 | err = alloc_css_id(css); | ||
4461 | if (err) | ||
4462 | goto err_free_all; | ||
4463 | } | ||
4464 | } | 4405 | } |
4465 | 4406 | ||
4466 | /* | 4407 | /* |
@@ -4925,12 +4866,6 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss) | |||
4925 | 4866 | ||
4926 | /* our new subsystem will be attached to the dummy hierarchy. */ | 4867 | /* our new subsystem will be attached to the dummy hierarchy. */ |
4927 | init_css(css, ss, cgroup_dummy_top); | 4868 | init_css(css, ss, cgroup_dummy_top); |
4928 | /* init_idr must be after init_css() because it sets css->id. */ | ||
4929 | if (ss->use_id) { | ||
4930 | ret = cgroup_init_idr(ss, css); | ||
4931 | if (ret) | ||
4932 | goto err_unload; | ||
4933 | } | ||
4934 | 4869 | ||
4935 | /* | 4870 | /* |
4936 | * Now we need to entangle the css into the existing css_sets. unlike | 4871 | * Now we need to entangle the css into the existing css_sets. unlike |
@@ -4996,9 +4931,6 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) | |||
4996 | 4931 | ||
4997 | offline_css(cgroup_css(cgroup_dummy_top, ss)); | 4932 | offline_css(cgroup_css(cgroup_dummy_top, ss)); |
4998 | 4933 | ||
4999 | if (ss->use_id) | ||
5000 | idr_destroy(&ss->idr); | ||
5001 | |||
5002 | /* deassign the subsys_id */ | 4934 | /* deassign the subsys_id */ |
5003 | cgroup_subsys[ss->subsys_id] = NULL; | 4935 | cgroup_subsys[ss->subsys_id] = NULL; |
5004 | 4936 | ||
@@ -5025,8 +4957,7 @@ void cgroup_unload_subsys(struct cgroup_subsys *ss) | |||
5025 | /* | 4957 | /* |
5026 | * remove subsystem's css from the cgroup_dummy_top and free it - | 4958 | * remove subsystem's css from the cgroup_dummy_top and free it - |
5027 | * need to free before marking as null because ss->css_free needs | 4959 | * need to free before marking as null because ss->css_free needs |
5028 | * the cgrp->subsys pointer to find their state. note that this | 4960 | * the cgrp->subsys pointer to find their state. |
5029 | * also takes care of freeing the css_id. | ||
5030 | */ | 4961 | */ |
5031 | ss->css_free(cgroup_css(cgroup_dummy_top, ss)); | 4962 | ss->css_free(cgroup_css(cgroup_dummy_top, ss)); |
5032 | RCU_INIT_POINTER(cgroup_dummy_top->subsys[ss->subsys_id], NULL); | 4963 | RCU_INIT_POINTER(cgroup_dummy_top->subsys[ss->subsys_id], NULL); |
@@ -5097,8 +5028,6 @@ int __init cgroup_init(void) | |||
5097 | for_each_builtin_subsys(ss, i) { | 5028 | for_each_builtin_subsys(ss, i) { |
5098 | if (!ss->early_init) | 5029 | if (!ss->early_init) |
5099 | cgroup_init_subsys(ss); | 5030 | cgroup_init_subsys(ss); |
5100 | if (ss->use_id) | ||
5101 | cgroup_init_idr(ss, init_css_set.subsys[ss->subsys_id]); | ||
5102 | } | 5031 | } |
5103 | 5032 | ||
5104 | /* allocate id for the dummy hierarchy */ | 5033 | /* allocate id for the dummy hierarchy */ |
@@ -5518,181 +5447,6 @@ static int __init cgroup_disable(char *str) | |||
5518 | } | 5447 | } |
5519 | __setup("cgroup_disable=", cgroup_disable); | 5448 | __setup("cgroup_disable=", cgroup_disable); |
5520 | 5449 | ||
5521 | /* | ||
5522 | * Functons for CSS ID. | ||
5523 | */ | ||
5524 | |||
5525 | /* to get ID other than 0, this should be called when !cgroup_is_dead() */ | ||
5526 | unsigned short css_id(struct cgroup_subsys_state *css) | ||
5527 | { | ||
5528 | struct css_id *cssid; | ||
5529 | |||
5530 | /* | ||
5531 | * This css_id() can return correct value when somone has refcnt | ||
5532 | * on this or this is under rcu_read_lock(). Once css->id is allocated, | ||
5533 | * it's unchanged until freed. | ||
5534 | */ | ||
5535 | cssid = rcu_dereference_raw(css->id); | ||
5536 | |||
5537 | if (cssid) | ||
5538 | return cssid->id; | ||
5539 | return 0; | ||
5540 | } | ||
5541 | EXPORT_SYMBOL_GPL(css_id); | ||
5542 | |||
5543 | /** | ||
5544 | * css_is_ancestor - test "root" css is an ancestor of "child" | ||
5545 | * @child: the css to be tested. | ||
5546 | * @root: the css supporsed to be an ancestor of the child. | ||
5547 | * | ||
5548 | * Returns true if "root" is an ancestor of "child" in its hierarchy. Because | ||
5549 | * this function reads css->id, the caller must hold rcu_read_lock(). | ||
5550 | * But, considering usual usage, the csses should be valid objects after test. | ||
5551 | * Assuming that the caller will do some action to the child if this returns | ||
5552 | * returns true, the caller must take "child";s reference count. | ||
5553 | * If "child" is valid object and this returns true, "root" is valid, too. | ||
5554 | */ | ||
5555 | |||
5556 | bool css_is_ancestor(struct cgroup_subsys_state *child, | ||
5557 | const struct cgroup_subsys_state *root) | ||
5558 | { | ||
5559 | struct css_id *child_id; | ||
5560 | struct css_id *root_id; | ||
5561 | |||
5562 | child_id = rcu_dereference(child->id); | ||
5563 | if (!child_id) | ||
5564 | return false; | ||
5565 | root_id = rcu_dereference(root->id); | ||
5566 | if (!root_id) | ||
5567 | return false; | ||
5568 | if (child_id->depth < root_id->depth) | ||
5569 | return false; | ||
5570 | if (child_id->stack[root_id->depth] != root_id->id) | ||
5571 | return false; | ||
5572 | return true; | ||
5573 | } | ||
5574 | |||
5575 | void free_css_id(struct cgroup_subsys *ss, struct cgroup_subsys_state *css) | ||
5576 | { | ||
5577 | struct css_id *id = rcu_dereference_protected(css->id, true); | ||
5578 | |||
5579 | /* When this is called before css_id initialization, id can be NULL */ | ||
5580 | if (!id) | ||
5581 | return; | ||
5582 | |||
5583 | BUG_ON(!ss->use_id); | ||
5584 | |||
5585 | rcu_assign_pointer(id->css, NULL); | ||
5586 | rcu_assign_pointer(css->id, NULL); | ||
5587 | spin_lock(&ss->id_lock); | ||
5588 | idr_remove(&ss->idr, id->id); | ||
5589 | spin_unlock(&ss->id_lock); | ||
5590 | kfree_rcu(id, rcu_head); | ||
5591 | } | ||
5592 | EXPORT_SYMBOL_GPL(free_css_id); | ||
5593 | |||
5594 | /* | ||
5595 | * This is called by init or create(). Then, calls to this function are | ||
5596 | * always serialized (By cgroup_mutex() at create()). | ||
5597 | */ | ||
5598 | |||
5599 | static struct css_id *get_new_cssid(struct cgroup_subsys *ss, int depth) | ||
5600 | { | ||
5601 | struct css_id *newid; | ||
5602 | int ret, size; | ||
5603 | |||
5604 | BUG_ON(!ss->use_id); | ||
5605 | |||
5606 | size = sizeof(*newid) + sizeof(unsigned short) * (depth + 1); | ||
5607 | newid = kzalloc(size, GFP_KERNEL); | ||
5608 | if (!newid) | ||
5609 | return ERR_PTR(-ENOMEM); | ||
5610 | |||
5611 | idr_preload(GFP_KERNEL); | ||
5612 | spin_lock(&ss->id_lock); | ||
5613 | /* Don't use 0. allocates an ID of 1-65535 */ | ||
5614 | ret = idr_alloc(&ss->idr, newid, 1, CSS_ID_MAX + 1, GFP_NOWAIT); | ||
5615 | spin_unlock(&ss->id_lock); | ||
5616 | idr_preload_end(); | ||
5617 | |||
5618 | /* Returns error when there are no free spaces for new ID.*/ | ||
5619 | if (ret < 0) | ||
5620 | goto err_out; | ||
5621 | |||
5622 | newid->id = ret; | ||
5623 | newid->depth = depth; | ||
5624 | return newid; | ||
5625 | err_out: | ||
5626 | kfree(newid); | ||
5627 | return ERR_PTR(ret); | ||
5628 | |||
5629 | } | ||
5630 | |||
5631 | static int __init_or_module cgroup_init_idr(struct cgroup_subsys *ss, | ||
5632 | struct cgroup_subsys_state *rootcss) | ||
5633 | { | ||
5634 | struct css_id *newid; | ||
5635 | |||
5636 | spin_lock_init(&ss->id_lock); | ||
5637 | idr_init(&ss->idr); | ||
5638 | |||
5639 | newid = get_new_cssid(ss, 0); | ||
5640 | if (IS_ERR(newid)) | ||
5641 | return PTR_ERR(newid); | ||
5642 | |||
5643 | newid->stack[0] = newid->id; | ||
5644 | RCU_INIT_POINTER(newid->css, rootcss); | ||
5645 | RCU_INIT_POINTER(rootcss->id, newid); | ||
5646 | return 0; | ||
5647 | } | ||
5648 | |||
5649 | static int alloc_css_id(struct cgroup_subsys_state *child_css) | ||
5650 | { | ||
5651 | struct cgroup_subsys_state *parent_css = css_parent(child_css); | ||
5652 | struct css_id *child_id, *parent_id; | ||
5653 | int i, depth; | ||
5654 | |||
5655 | parent_id = rcu_dereference_protected(parent_css->id, true); | ||
5656 | depth = parent_id->depth + 1; | ||
5657 | |||
5658 | child_id = get_new_cssid(child_css->ss, depth); | ||
5659 | if (IS_ERR(child_id)) | ||
5660 | return PTR_ERR(child_id); | ||
5661 | |||
5662 | for (i = 0; i < depth; i++) | ||
5663 | child_id->stack[i] = parent_id->stack[i]; | ||
5664 | child_id->stack[depth] = child_id->id; | ||
5665 | /* | ||
5666 | * child_id->css pointer will be set after this cgroup is available | ||
5667 | * see cgroup_populate_dir() | ||
5668 | */ | ||
5669 | rcu_assign_pointer(child_css->id, child_id); | ||
5670 | |||
5671 | return 0; | ||
5672 | } | ||
5673 | |||
5674 | /** | ||
5675 | * css_lookup - lookup css by id | ||
5676 | * @ss: cgroup subsys to be looked into. | ||
5677 | * @id: the id | ||
5678 | * | ||
5679 | * Returns pointer to cgroup_subsys_state if there is valid one with id. | ||
5680 | * NULL if not. Should be called under rcu_read_lock() | ||
5681 | */ | ||
5682 | struct cgroup_subsys_state *css_lookup(struct cgroup_subsys *ss, int id) | ||
5683 | { | ||
5684 | struct css_id *cssid = NULL; | ||
5685 | |||
5686 | BUG_ON(!ss->use_id); | ||
5687 | cssid = idr_find(&ss->idr, id); | ||
5688 | |||
5689 | if (unlikely(!cssid)) | ||
5690 | return NULL; | ||
5691 | |||
5692 | return rcu_dereference(cssid->css); | ||
5693 | } | ||
5694 | EXPORT_SYMBOL_GPL(css_lookup); | ||
5695 | |||
5696 | /** | 5450 | /** |
5697 | * css_from_dir - get corresponding css from the dentry of a cgroup dir | 5451 | * css_from_dir - get corresponding css from the dentry of a cgroup dir |
5698 | * @dentry: directory dentry of interest | 5452 | * @dentry: directory dentry of interest |
diff --git a/kernel/elfcore.c b/kernel/elfcore.c index ff915efef66d..e556751d15d9 100644 --- a/kernel/elfcore.c +++ b/kernel/elfcore.c | |||
@@ -1,23 +1,19 @@ | |||
1 | #include <linux/elf.h> | 1 | #include <linux/elf.h> |
2 | #include <linux/fs.h> | 2 | #include <linux/fs.h> |
3 | #include <linux/mm.h> | 3 | #include <linux/mm.h> |
4 | 4 | #include <linux/binfmts.h> | |
5 | #include <asm/elf.h> | ||
6 | |||
7 | 5 | ||
8 | Elf_Half __weak elf_core_extra_phdrs(void) | 6 | Elf_Half __weak elf_core_extra_phdrs(void) |
9 | { | 7 | { |
10 | return 0; | 8 | return 0; |
11 | } | 9 | } |
12 | 10 | ||
13 | int __weak elf_core_write_extra_phdrs(struct file *file, loff_t offset, size_t *size, | 11 | int __weak elf_core_write_extra_phdrs(struct coredump_params *cprm, loff_t offset) |
14 | unsigned long limit) | ||
15 | { | 12 | { |
16 | return 1; | 13 | return 1; |
17 | } | 14 | } |
18 | 15 | ||
19 | int __weak elf_core_write_extra_data(struct file *file, size_t *size, | 16 | int __weak elf_core_write_extra_data(struct coredump_params *cprm) |
20 | unsigned long limit) | ||
21 | { | 17 | { |
22 | return 1; | 18 | return 1; |
23 | } | 19 | } |
diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 42086551a24a..06c62de9c711 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c | |||
@@ -132,6 +132,12 @@ out: | |||
132 | return ERR_PTR(err); | 132 | return ERR_PTR(err); |
133 | } | 133 | } |
134 | 134 | ||
135 | static void delayed_free_pidns(struct rcu_head *p) | ||
136 | { | ||
137 | kmem_cache_free(pid_ns_cachep, | ||
138 | container_of(p, struct pid_namespace, rcu)); | ||
139 | } | ||
140 | |||
135 | static void destroy_pid_namespace(struct pid_namespace *ns) | 141 | static void destroy_pid_namespace(struct pid_namespace *ns) |
136 | { | 142 | { |
137 | int i; | 143 | int i; |
@@ -140,7 +146,7 @@ static void destroy_pid_namespace(struct pid_namespace *ns) | |||
140 | for (i = 0; i < PIDMAP_ENTRIES; i++) | 146 | for (i = 0; i < PIDMAP_ENTRIES; i++) |
141 | kfree(ns->pidmap[i].page); | 147 | kfree(ns->pidmap[i].page); |
142 | put_user_ns(ns->user_ns); | 148 | put_user_ns(ns->user_ns); |
143 | kmem_cache_free(pid_ns_cachep, ns); | 149 | call_rcu(&ns->rcu, delayed_free_pidns); |
144 | } | 150 | } |
145 | 151 | ||
146 | struct pid_namespace *copy_pid_ns(unsigned long flags, | 152 | struct pid_namespace *copy_pid_ns(unsigned long flags, |
diff --git a/kernel/signal.c b/kernel/signal.c index ded28b91fa53..940b30ee9a30 100644 --- a/kernel/signal.c +++ b/kernel/signal.c | |||
@@ -2723,7 +2723,7 @@ COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, | |||
2723 | 2723 | ||
2724 | #ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER | 2724 | #ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER |
2725 | 2725 | ||
2726 | int copy_siginfo_to_user(siginfo_t __user *to, siginfo_t *from) | 2726 | int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from) |
2727 | { | 2727 | { |
2728 | int err; | 2728 | int err; |
2729 | 2729 | ||