[PATCH] rename struct pspace to struct pid_namespace

Rename struct pspace to struct pid_namespace for consistency with other
namespaces (uts_namespace and ipc_namespace).  Also rename
include/linux/pspace.h to include/linux/pid_namespace.h and variables from
pspace to pid_ns.
Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Signed-off-by: Cedric Le Goater <clg@fr.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/proc/proc_misc.c

@@ -45,7 +45,7 @@
 #include <linux/sysrq.h>
 #include <linux/vmalloc.h>
 #include <linux/crash_dump.h>
-#include <linux/pspace.h>
+#include <linux/pid_namespace.h>
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
 #include <asm/io.h>
@@ -92,7 +92,7 @@ static int loadavg_read_proc(char *page, char **start, off_t off,
 		LOAD_INT(a), LOAD_FRAC(a),
 		LOAD_INT(b), LOAD_FRAC(b),
 		LOAD_INT(c), LOAD_FRAC(c),
-		nr_running(), nr_threads, init_pspace.last_pid);
+		nr_running(), nr_threads, init_pid_ns.last_pid);
 	return proc_calc_metrics(page, start, off, count, eof, len);
 }
 

include/linux/pspace.h → include/linux/pid_namespace.h

-#ifndef _LINUX_PSPACE_H
-#define _LINUX_PSPACE_H
+#ifndef _LINUX_PID_NS_H
+#define _LINUX_PID_NS_H
 
 #include <linux/sched.h>
 #include <linux/mm.h>
@@ -13,11 +13,11 @@ struct pidmap {
 
 #define PIDMAP_ENTRIES         ((PID_MAX_LIMIT + 8*PAGE_SIZE - 1)/PAGE_SIZE/8)
 
-struct pspace {
+struct pid_namespace {
        struct pidmap pidmap[PIDMAP_ENTRIES];
        int last_pid;
 };
 
-extern struct pspace init_pspace;
+extern struct pid_namespace init_pid_ns;
 
-#endif /* _LINUX_PSPACE_H */
+#endif /* _LINUX_PID_NS_H */

kernel/pid.c

@@ -26,7 +26,7 @@
 #include <linux/init.h>
 #include <linux/bootmem.h>
 #include <linux/hash.h>
-#include <linux/pspace.h>
+#include <linux/pid_namespace.h>
 
 #define pid_hashfn(nr) hash_long((unsigned long)nr, pidhash_shift)
 static struct hlist_head *pid_hash;
@@ -43,9 +43,10 @@ int pid_max_max = PID_MAX_LIMIT;
 #define BITS_PER_PAGE		(PAGE_SIZE*8)
 #define BITS_PER_PAGE_MASK	(BITS_PER_PAGE-1)
 
-static inline int mk_pid(struct pspace *pspace, struct pidmap *map, int off)
+static inline int mk_pid(struct pid_namespace *pid_ns,
+		struct pidmap *map, int off)
 {
-	return (map - pspace->pidmap)*BITS_PER_PAGE + off;
+	return (map - pid_ns->pidmap)*BITS_PER_PAGE + off;
 }
 
 #define find_next_offset(map, off)					\
@@ -57,7 +58,7 @@ static inline int mk_pid(struct pspace *pspace, struct pidmap *map, int off)
  * value does not cause lots of bitmaps to be allocated, but
  * the scheme scales to up to 4 million PIDs, runtime.
  */
-struct pspace init_pspace = {
+struct pid_namespace init_pid_ns = {
 	.pidmap = {
 		[ 0 ... PIDMAP_ENTRIES-1] = { ATOMIC_INIT(BITS_PER_PAGE), NULL }
 	},
@@ -80,25 +81,25 @@ struct pspace init_pspace = {
 
 static  __cacheline_aligned_in_smp DEFINE_SPINLOCK(pidmap_lock);
 
-static fastcall void free_pidmap(struct pspace *pspace, int pid)
+static fastcall void free_pidmap(struct pid_namespace *pid_ns, int pid)
 {
-	struct pidmap *map = pspace->pidmap + pid / BITS_PER_PAGE;
+	struct pidmap *map = pid_ns->pidmap + pid / BITS_PER_PAGE;
 	int offset = pid & BITS_PER_PAGE_MASK;
 
 	clear_bit(offset, map->page);
 	atomic_inc(&map->nr_free);
 }
 
-static int alloc_pidmap(struct pspace *pspace)
+static int alloc_pidmap(struct pid_namespace *pid_ns)
 {
-	int i, offset, max_scan, pid, last = pspace->last_pid;
+	int i, offset, max_scan, pid, last = pid_ns->last_pid;
 	struct pidmap *map;
 
 	pid = last + 1;
 	if (pid >= pid_max)
 		pid = RESERVED_PIDS;
 	offset = pid & BITS_PER_PAGE_MASK;
-	map = &pspace->pidmap[pid/BITS_PER_PAGE];
+	map = &pid_ns->pidmap[pid/BITS_PER_PAGE];
 	max_scan = (pid_max + BITS_PER_PAGE - 1)/BITS_PER_PAGE - !offset;
 	for (i = 0; i <= max_scan; ++i) {
 		if (unlikely(!map->page)) {
@@ -120,11 +121,11 @@ static int alloc_pidmap(struct pspace *pspace)
 			do {
 				if (!test_and_set_bit(offset, map->page)) {
 					atomic_dec(&map->nr_free);
-					pspace->last_pid = pid;
+					pid_ns->last_pid = pid;
 					return pid;
 				}
 				offset = find_next_offset(map, offset);
-				pid = mk_pid(pspace, map, offset);
+				pid = mk_pid(pid_ns, map, offset);
 			/*
 			 * find_next_offset() found a bit, the pid from it
 			 * is in-bounds, and if we fell back to the last
@@ -135,34 +136,34 @@ static int alloc_pidmap(struct pspace *pspace)
 					(i != max_scan || pid < last ||
 					    !((last+1) & BITS_PER_PAGE_MASK)));
 		}
-		if (map < &pspace->pidmap[(pid_max-1)/BITS_PER_PAGE]) {
+		if (map < &pid_ns->pidmap[(pid_max-1)/BITS_PER_PAGE]) {
 			++map;
 			offset = 0;
 		} else {
-			map = &pspace->pidmap[0];
+			map = &pid_ns->pidmap[0];
 			offset = RESERVED_PIDS;
 			if (unlikely(last == offset))
 				break;
 		}
-		pid = mk_pid(pspace, map, offset);
+		pid = mk_pid(pid_ns, map, offset);
 	}
 	return -1;
 }
 
-static int next_pidmap(struct pspace *pspace, int last)
+static int next_pidmap(struct pid_namespace *pid_ns, int last)
 {
 	int offset;
 	struct pidmap *map, *end;
 
 	offset = (last + 1) & BITS_PER_PAGE_MASK;
-	map = &pspace->pidmap[(last + 1)/BITS_PER_PAGE];
-	end = &pspace->pidmap[PIDMAP_ENTRIES];
+	map = &pid_ns->pidmap[(last + 1)/BITS_PER_PAGE];
+	end = &pid_ns->pidmap[PIDMAP_ENTRIES];
 	for (; map < end; map++, offset = 0) {
 		if (unlikely(!map->page))
 			continue;
 		offset = find_next_bit((map)->page, BITS_PER_PAGE, offset);
 		if (offset < BITS_PER_PAGE)
-			return mk_pid(pspace, map, offset);
+			return mk_pid(pid_ns, map, offset);
 	}
 	return -1;
 }
@@ -192,7 +193,7 @@ fastcall void free_pid(struct pid *pid)
 	hlist_del_rcu(&pid->pid_chain);
 	spin_unlock_irqrestore(&pidmap_lock, flags);
 
-	free_pidmap(&init_pspace, pid->nr);
+	free_pidmap(&init_pid_ns, pid->nr);
 	call_rcu(&pid->rcu, delayed_put_pid);
 }
 
@@ -206,7 +207,7 @@ struct pid *alloc_pid(void)
 	if (!pid)
 		goto out;
 
-	nr = alloc_pidmap(&init_pspace);
+	nr = alloc_pidmap(&init_pid_ns);
 	if (nr < 0)
 		goto out_free;
 
@@ -348,7 +349,7 @@ struct pid *find_ge_pid(int nr)
 		pid = find_pid(nr);
 		if (pid)
 			break;
-		nr = next_pidmap(&init_pspace, nr);
+		nr = next_pidmap(&init_pid_ns, nr);
 	} while (nr > 0);
 
 	return pid;
@@ -382,10 +383,10 @@ void __init pidhash_init(void)
 
 void __init pidmap_init(void)
 {
-	init_pspace.pidmap[0].page = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	init_pid_ns.pidmap[0].page = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	/* Reserve PID 0. We never call free_pidmap(0) */
-	set_bit(0, init_pspace.pidmap[0].page);
-	atomic_dec(&init_pspace.pidmap[0].nr_free);
+	set_bit(0, init_pid_ns.pidmap[0].page);
+	atomic_dec(&init_pid_ns.pidmap[0].nr_free);
 
 	pid_cachep = kmem_cache_create("pid", sizeof(struct pid),
 					__alignof__(struct pid),