From c0add7fd05ff99c3a516c78eb6b1e6460a3efdae Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Fri, 7 Jun 2013 17:38:58 -0700 Subject: target: Add transport_init_session_tags using per-cpu ida This patch adds lib/idr.c based transport_init_session_tags() logic that allows fabric drivers to setup a per-cpu se_sess->sess_tag_pool and associated se_sess->sess_cmd_map for basic tagged pre-allocation of fabric descriptor sized memory. v5 changes: - Convert to percpu_ida.h include v4 changes: - Add transport_alloc_session_tags() for fabrics that need early transport_init_session() v3 changes: - Update to percpu-ida usage Cc: Kent Overstreet Cc: Asias He Cc: Michael S. Tsirkin Reviewed-by: Asias He Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_transport.c | 48 ++++++++++++++++++++++++++++++++++ include/target/target_core_base.h | 5 ++++ include/target/target_core_fabric.h | 3 +++ 3 files changed, 56 insertions(+) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 7172d005d063..98ec7110873b 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -232,6 +232,50 @@ struct se_session *transport_init_session(void) } EXPORT_SYMBOL(transport_init_session); +int transport_alloc_session_tags(struct se_session *se_sess, + unsigned int tag_num, unsigned int tag_size) +{ + int rc; + + se_sess->sess_cmd_map = kzalloc(tag_num * tag_size, GFP_KERNEL); + if (!se_sess->sess_cmd_map) { + pr_err("Unable to allocate se_sess->sess_cmd_map\n"); + return -ENOMEM; + } + + rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num); + if (rc < 0) { + pr_err("Unable to init se_sess->sess_tag_pool," + " tag_num: %u\n", tag_num); + kfree(se_sess->sess_cmd_map); + se_sess->sess_cmd_map = NULL; + return -ENOMEM; + } + + return 0; +} +EXPORT_SYMBOL(transport_alloc_session_tags); + +struct se_session *transport_init_session_tags(unsigned int tag_num, + unsigned int tag_size) +{ + struct se_session *se_sess; + int rc; + + se_sess = transport_init_session(); + if (IS_ERR(se_sess)) + return se_sess; + + rc = transport_alloc_session_tags(se_sess, tag_num, tag_size); + if (rc < 0) { + transport_free_session(se_sess); + return ERR_PTR(-ENOMEM); + } + + return se_sess; +} +EXPORT_SYMBOL(transport_init_session_tags); + /* * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called. */ @@ -367,6 +411,10 @@ EXPORT_SYMBOL(transport_deregister_session_configfs); void transport_free_session(struct se_session *se_sess) { + if (se_sess->sess_cmd_map) { + percpu_ida_destroy(&se_sess->sess_tag_pool); + kfree(se_sess->sess_cmd_map); + } kmem_cache_free(se_sess_cache, se_sess); } EXPORT_SYMBOL(transport_free_session); diff --git a/include/target/target_core_base.h b/include/target/target_core_base.h index e34fc904f2e1..bd55acd43005 100644 --- a/include/target/target_core_base.h +++ b/include/target/target_core_base.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include #include @@ -415,6 +416,8 @@ struct se_cmd { enum dma_data_direction data_direction; /* For SAM Task Attribute */ int sam_task_attr; + /* Used for se_sess->sess_tag_pool */ + unsigned int map_tag; /* Transport protocol dependent state, see transport_state_table */ enum transport_state_table t_state; unsigned cmd_wait_set:1; @@ -536,6 +539,8 @@ struct se_session { struct list_head sess_wait_list; spinlock_t sess_cmd_lock; struct kref sess_kref; + void *sess_cmd_map; + struct percpu_ida sess_tag_pool; }; struct se_device; diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 7a16178424f9..d559c36692af 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -84,6 +84,9 @@ struct target_core_fabric_ops { }; struct se_session *transport_init_session(void); +int transport_alloc_session_tags(struct se_session *, unsigned int, + unsigned int); +struct se_session *transport_init_session_tags(unsigned int, unsigned int); void __transport_register_session(struct se_portal_group *, struct se_node_acl *, struct se_session *, void *); void transport_register_session(struct se_portal_group *, -- cgit v1.2.2 ederman <ebiederm@xmission.com> 2012-11-19 08:57:31 -0500 pidns: Capture the user namespace and filter ns_last_pid' href='/cgit/cgit.cgi/litmus-rt-ext-res.git/commit/kernel/pid_namespace.c?id=49f4d8b93ccf9454284b6f524b96c66d8d7fbccc'>49f4d8b93ccf
1
2
3
4
5
6
7
8
9
10
11
12











                                                                      
                                 

                           
                       
                       
                          
                         
                         





















































                                                                                





                                                                                       


                                                                  

                                                                                 

                                 
                                                      






                                       
 
                      
                                                          










                                                            



                                              
                             
                          
                                               
                                           
                                          
                                                     



                                                              
                                            
                                                                  







                                           
                            





                                                           
                                      

                                            
                                 


                                           

                                                                     
 
                                    
                                          

                                                  
                                                     

 
                                          
 
                                 

                                                            
                                  
 
 









                                                      
 
                              




                                                       

                                                


                                                                   



                                                                        
















                                                                               

                                
                                                            

                                                                      


                                  



                                             
                                                                




                                                       

                                                               
                                                      

                  

                                                        


                              
                                          
 


                                                                  
                             


               
                                


                                                                 
                                                                   

                                      
                                                                 







                                                                         
                                     
                                                                     

 

                    





                                                                          

                                   


           
                                                                        
                                       
 




























                                                        




















                                                                   

                                                       























                                                                     





                                          





                                                    
                                     

  


                                                              

                                
                                                           
      



                                
/*
 * Pid namespaces
 *
 * Authors:
 *    (C) 2007 Pavel Emelyanov <xemul@openvz.org>, OpenVZ, SWsoft Inc.
 *    (C) 2007 Sukadev Bhattiprolu <sukadev@us.ibm.com>, IBM
 *     Many thanks to Oleg Nesterov for comments and help
 *
 */

#include <linux/pid.h>
#include <linux/pid_namespace.h>
#include <linux/user_namespace.h>
#include <linux/syscalls.h>
#include <linux/err.h>
#include <linux/acct.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>
#include <linux/reboot.h>
#include <linux/export.h>

#define BITS_PER_PAGE		(PAGE_SIZE*8)

struct pid_cache {
	int nr_ids;
	char name[16];
	struct kmem_cache *cachep;
	struct list_head list;
};

static LIST_HEAD(pid_caches_lh);
static DEFINE_MUTEX(pid_caches_mutex);
static struct kmem_cache *pid_ns_cachep;

/*
 * creates the kmem cache to allocate pids from.
 * @nr_ids: the number of numerical ids this pid will have to carry
 */

static struct kmem_cache *create_pid_cachep(int nr_ids)
{
	struct pid_cache *pcache;
	struct kmem_cache *cachep;

	mutex_lock(&pid_caches_mutex);
	list_for_each_entry(pcache, &pid_caches_lh, list)
		if (pcache->nr_ids == nr_ids)
			goto out;

	pcache = kmalloc(sizeof(struct pid_cache), GFP_KERNEL);
	if (pcache == NULL)
		goto err_alloc;

	snprintf(pcache->name, sizeof(pcache->name), "pid_%d", nr_ids);
	cachep = kmem_cache_create(pcache->name,
			sizeof(struct pid) + (nr_ids - 1) * sizeof(struct upid),
			0, SLAB_HWCACHE_ALIGN, NULL);
	if (cachep == NULL)
		goto err_cachep;

	pcache->nr_ids = nr_ids;
	pcache->cachep = cachep;
	list_add(&pcache->list, &pid_caches_lh);
out:
	mutex_unlock(&pid_caches_mutex);
	return pcache->cachep;

err_cachep:
	kfree(pcache);
err_alloc:
	mutex_unlock(&pid_caches_mutex);
	return NULL;
}

static void proc_cleanup_work(struct work_struct *work)
{
	struct pid_namespace *ns = container_of(work, struct pid_namespace, proc_work);
	pid_ns_release_proc(ns);
}

/* MAX_PID_NS_LEVEL is needed for limiting size of 'struct pid' */
#define MAX_PID_NS_LEVEL 32

static struct pid_namespace *create_pid_namespace(struct user_namespace *user_ns,
	struct pid_namespace *parent_pid_ns)
{
	struct pid_namespace *ns;
	unsigned int level = parent_pid_ns->level + 1;
	int i;
	int err;

	if (level > MAX_PID_NS_LEVEL) {
		err = -EINVAL;
		goto out;
	}

	err = -ENOMEM;
	ns = kmem_cache_zalloc(pid_ns_cachep, GFP_KERNEL);
	if (ns == NULL)
		goto out;

	ns->pidmap[0].page = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!ns->pidmap[0].page)
		goto out_free;

	ns->pid_cachep = create_pid_cachep(level + 1);
	if (ns->pid_cachep == NULL)
		goto out_free_map;

	err = proc_alloc_inum(&ns->proc_inum);
	if (err)
		goto out_free_map;

	kref_init(&ns->kref);
	ns->level = level;
	ns->parent = get_pid_ns(parent_pid_ns);
	ns->user_ns = get_user_ns(user_ns);
	ns->nr_hashed = PIDNS_HASH_ADDING;
	INIT_WORK(&ns->proc_work, proc_cleanup_work);

	set_bit(0, ns->pidmap[0].page);
	atomic_set(&ns->pidmap[0].nr_free, BITS_PER_PAGE - 1);

	for (i = 1; i < PIDMAP_ENTRIES; i++)
		atomic_set(&ns->pidmap[i].nr_free, BITS_PER_PAGE);

	return ns;

out_free_map:
	kfree(ns->pidmap[0].page);
out_free:
	kmem_cache_free(pid_ns_cachep, ns);
out:
	return ERR_PTR(err);
}

static void destroy_pid_namespace(struct pid_namespace *ns)
{
	int i;

	proc_free_inum(ns->proc_inum);
	for (i = 0; i < PIDMAP_ENTRIES; i++)
		kfree(ns->pidmap[i].page);
	put_user_ns(ns->user_ns);
	kmem_cache_free(pid_ns_cachep, ns);
}

struct pid_namespace *copy_pid_ns(unsigned long flags,
	struct user_namespace *user_ns, struct pid_namespace *old_ns)
{
	if (!(flags & CLONE_NEWPID))
		return get_pid_ns(old_ns);
	if (task_active_pid_ns(current) != old_ns)
		return ERR_PTR(-EINVAL);
	return create_pid_namespace(user_ns, old_ns);
}

static void free_pid_ns(struct kref *kref)
{
	struct pid_namespace *ns;

	ns = container_of(kref, struct pid_namespace, kref);
	destroy_pid_namespace(ns);
}

void put_pid_ns(struct pid_namespace *ns)
{
	struct pid_namespace *parent;

	while (ns != &init_pid_ns) {
		parent = ns->parent;
		if (!kref_put(&ns->kref, free_pid_ns))
			break;
		ns = parent;
	}
}
EXPORT_SYMBOL_GPL(put_pid_ns);

void zap_pid_ns_processes(struct pid_namespace *pid_ns)
{
	int nr;
	int rc;
	struct task_struct *task, *me = current;

	/* Don't allow any more processes into the pid namespace */
	disable_pid_allocation(pid_ns);

	/* Ignore SIGCHLD causing any terminated children to autoreap */
	spin_lock_irq(&me->sighand->siglock);
	me->sighand->action[SIGCHLD - 1].sa.sa_handler = SIG_IGN;
	spin_unlock_irq(&me->sighand->siglock);

	/*
	 * The last thread in the cgroup-init thread group is terminating.
	 * Find remaining pid_ts in the namespace, signal and wait for them
	 * to exit.
	 *