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-rw-r--r--lib/Kconfig.debug12
-rw-r--r--lib/Makefile6
-rw-r--r--lib/bcd.c14
-rw-r--r--lib/cmdline.c16
-rw-r--r--lib/debugobjects.c19
-rw-r--r--lib/idr.c142
-rw-r--r--lib/inflate.c52
-rw-r--r--lib/iomap.c3
-rw-r--r--lib/kobject.c9
-rw-r--r--lib/kobject_uevent.c6
-rw-r--r--lib/list_debug.c50
-rw-r--r--lib/lzo/lzo1x_decompress.c6
-rw-r--r--lib/plist.c13
-rw-r--r--lib/radix-tree.c180
-rw-r--r--lib/ratelimit.c55
-rw-r--r--lib/show_mem.c63
-rw-r--r--lib/swiotlb.c4
-rw-r--r--lib/syscall.c75
18 files changed, 530 insertions, 195 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 882c51048993..e1d4764435ed 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -505,6 +505,18 @@ config DEBUG_WRITECOUNT
If unsure, say N.
+config DEBUG_MEMORY_INIT
+ bool "Debug memory initialisation" if EMBEDDED
+ default !EMBEDDED
+ help
+ Enable this for additional checks during memory initialisation.
+ The sanity checks verify aspects of the VM such as the memory model
+ and other information provided by the architecture. Verbose
+ information will be printed at KERN_DEBUG loglevel depending
+ on the mminit_loglevel= command-line option.
+
+ If unsure, say Y
+
config DEBUG_LIST
bool "Debug linked list manipulation"
depends on DEBUG_KERNEL
diff --git a/lib/Makefile b/lib/Makefile
index 818c4d455518..3b1f94bbe9de 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -11,14 +11,14 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
rbtree.o radix-tree.o dump_stack.o \
idr.o int_sqrt.o extable.o prio_tree.o \
sha1.o irq_regs.o reciprocal_div.o argv_split.o \
- proportions.o prio_heap.o ratelimit.o
+ proportions.o prio_heap.o ratelimit.o show_mem.o
lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o kref.o klist.o
-obj-y += div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
+obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \
bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
@@ -78,6 +78,8 @@ lib-$(CONFIG_GENERIC_BUG) += bug.o
obj-$(CONFIG_HAVE_LMB) += lmb.o
+obj-$(CONFIG_HAVE_ARCH_TRACEHOOK) += syscall.o
+
hostprogs-y := gen_crc32table
clean-files := crc32table.h
diff --git a/lib/bcd.c b/lib/bcd.c
new file mode 100644
index 000000000000..d74257fd0fe7
--- /dev/null
+++ b/lib/bcd.c
@@ -0,0 +1,14 @@
+#include <linux/bcd.h>
+#include <linux/module.h>
+
+unsigned bcd2bin(unsigned char val)
+{
+ return (val & 0x0f) + (val >> 4) * 10;
+}
+EXPORT_SYMBOL(bcd2bin);
+
+unsigned char bin2bcd(unsigned val)
+{
+ return ((val / 10) << 4) + val % 10;
+}
+EXPORT_SYMBOL(bin2bcd);
diff --git a/lib/cmdline.c b/lib/cmdline.c
index f596c08d213a..5ba8a942a478 100644
--- a/lib/cmdline.c
+++ b/lib/cmdline.c
@@ -116,7 +116,7 @@ char *get_options(const char *str, int nints, int *ints)
/**
* memparse - parse a string with mem suffixes into a number
* @ptr: Where parse begins
- * @retptr: (output) Pointer to next char after parse completes
+ * @retptr: (output) Optional pointer to next char after parse completes
*
* Parses a string into a number. The number stored at @ptr is
* potentially suffixed with %K (for kilobytes, or 1024 bytes),
@@ -126,11 +126,13 @@ char *get_options(const char *str, int nints, int *ints)
* megabyte, or one gigabyte, respectively.
*/
-unsigned long long memparse (char *ptr, char **retptr)
+unsigned long long memparse(char *ptr, char **retptr)
{
- unsigned long long ret = simple_strtoull (ptr, retptr, 0);
+ char *endptr; /* local pointer to end of parsed string */
- switch (**retptr) {
+ unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
+
+ switch (*endptr) {
case 'G':
case 'g':
ret <<= 10;
@@ -140,10 +142,14 @@ unsigned long long memparse (char *ptr, char **retptr)
case 'K':
case 'k':
ret <<= 10;
- (*retptr)++;
+ endptr++;
default:
break;
}
+
+ if (retptr)
+ *retptr = endptr;
+
return ret;
}
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 85b18d79be89..45a6bde762d1 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -205,9 +205,8 @@ static void debug_print_object(struct debug_obj *obj, char *msg)
if (limit < 5 && obj->descr != descr_test) {
limit++;
- printk(KERN_ERR "ODEBUG: %s %s object type: %s\n", msg,
+ WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg,
obj_states[obj->state], obj->descr->name);
- WARN_ON(1);
}
debug_objects_warnings++;
}
@@ -226,15 +225,13 @@ debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
static void debug_object_is_on_stack(void *addr, int onstack)
{
- void *stack = current->stack;
int is_on_stack;
static int limit;
if (limit > 4)
return;
- is_on_stack = (addr >= stack && addr < (stack + THREAD_SIZE));
-
+ is_on_stack = object_is_on_stack(addr);
if (is_on_stack == onstack)
return;
@@ -735,26 +732,22 @@ check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
obj = lookup_object(addr, db);
if (!obj && state != ODEBUG_STATE_NONE) {
- printk(KERN_ERR "ODEBUG: selftest object not found\n");
- WARN_ON(1);
+ WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
goto out;
}
if (obj && obj->state != state) {
- printk(KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
+ WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
obj->state, state);
- WARN_ON(1);
goto out;
}
if (fixups != debug_objects_fixups) {
- printk(KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
+ WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
fixups, debug_objects_fixups);
- WARN_ON(1);
goto out;
}
if (warnings != debug_objects_warnings) {
- printk(KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
+ WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
warnings, debug_objects_warnings);
- WARN_ON(1);
goto out;
}
res = 0;
diff --git a/lib/idr.c b/lib/idr.c
index 7a02e173f027..e728c7fccc4d 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -6,6 +6,8 @@
* Modified by George Anzinger to reuse immediately and to use
* find bit instructions. Also removed _irq on spinlocks.
*
+ * Modified by Nadia Derbey to make it RCU safe.
+ *
* Small id to pointer translation service.
*
* It uses a radix tree like structure as a sparse array indexed
@@ -35,7 +37,7 @@
static struct kmem_cache *idr_layer_cache;
-static struct idr_layer *alloc_layer(struct idr *idp)
+static struct idr_layer *get_from_free_list(struct idr *idp)
{
struct idr_layer *p;
unsigned long flags;
@@ -50,15 +52,28 @@ static struct idr_layer *alloc_layer(struct idr *idp)
return(p);
}
+static void idr_layer_rcu_free(struct rcu_head *head)
+{
+ struct idr_layer *layer;
+
+ layer = container_of(head, struct idr_layer, rcu_head);
+ kmem_cache_free(idr_layer_cache, layer);
+}
+
+static inline void free_layer(struct idr_layer *p)
+{
+ call_rcu(&p->rcu_head, idr_layer_rcu_free);
+}
+
/* only called when idp->lock is held */
-static void __free_layer(struct idr *idp, struct idr_layer *p)
+static void __move_to_free_list(struct idr *idp, struct idr_layer *p)
{
p->ary[0] = idp->id_free;
idp->id_free = p;
idp->id_free_cnt++;
}
-static void free_layer(struct idr *idp, struct idr_layer *p)
+static void move_to_free_list(struct idr *idp, struct idr_layer *p)
{
unsigned long flags;
@@ -66,7 +81,7 @@ static void free_layer(struct idr *idp, struct idr_layer *p)
* Depends on the return element being zeroed.
*/
spin_lock_irqsave(&idp->lock, flags);
- __free_layer(idp, p);
+ __move_to_free_list(idp, p);
spin_unlock_irqrestore(&idp->lock, flags);
}
@@ -96,7 +111,7 @@ static void idr_mark_full(struct idr_layer **pa, int id)
* @gfp_mask: memory allocation flags
*
* This function should be called prior to locking and calling the
- * following function. It preallocates enough memory to satisfy
+ * idr_get_new* functions. It preallocates enough memory to satisfy
* the worst possible allocation.
*
* If the system is REALLY out of memory this function returns 0,
@@ -109,7 +124,7 @@ int idr_pre_get(struct idr *idp, gfp_t gfp_mask)
new = kmem_cache_alloc(idr_layer_cache, gfp_mask);
if (new == NULL)
return (0);
- free_layer(idp, new);
+ move_to_free_list(idp, new);
}
return 1;
}
@@ -143,7 +158,7 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
/* if already at the top layer, we need to grow */
if (!(p = pa[l])) {
*starting_id = id;
- return -2;
+ return IDR_NEED_TO_GROW;
}
/* If we need to go up one layer, continue the
@@ -160,16 +175,17 @@ static int sub_alloc(struct idr *idp, int *starting_id, struct idr_layer **pa)
id = ((id >> sh) ^ n ^ m) << sh;
}
if ((id >= MAX_ID_BIT) || (id < 0))
- return -3;
+ return IDR_NOMORE_SPACE;
if (l == 0)
break;
/*
* Create the layer below if it is missing.
*/
if (!p->ary[m]) {
- if (!(new = alloc_layer(idp)))
+ new = get_from_free_list(idp);
+ if (!new)
return -1;
- p->ary[m] = new;
+ rcu_assign_pointer(p->ary[m], new);
p->count++;
}
pa[l--] = p;
@@ -192,7 +208,7 @@ build_up:
p = idp->top;
layers = idp->layers;
if (unlikely(!p)) {
- if (!(p = alloc_layer(idp)))
+ if (!(p = get_from_free_list(idp)))
return -1;
layers = 1;
}
@@ -204,7 +220,7 @@ build_up:
layers++;
if (!p->count)
continue;
- if (!(new = alloc_layer(idp))) {
+ if (!(new = get_from_free_list(idp))) {
/*
* The allocation failed. If we built part of
* the structure tear it down.
@@ -214,7 +230,7 @@ build_up:
p = p->ary[0];
new->ary[0] = NULL;
new->bitmap = new->count = 0;
- __free_layer(idp, new);
+ __move_to_free_list(idp, new);
}
spin_unlock_irqrestore(&idp->lock, flags);
return -1;
@@ -225,10 +241,10 @@ build_up:
__set_bit(0, &new->bitmap);
p = new;
}
- idp->top = p;
+ rcu_assign_pointer(idp->top, p);
idp->layers = layers;
v = sub_alloc(idp, &id, pa);
- if (v == -2)
+ if (v == IDR_NEED_TO_GROW)
goto build_up;
return(v);
}
@@ -244,7 +260,8 @@ static int idr_get_new_above_int(struct idr *idp, void *ptr, int starting_id)
* Successfully found an empty slot. Install the user
* pointer and mark the slot full.
*/
- pa[0]->ary[id & IDR_MASK] = (struct idr_layer *)ptr;
+ rcu_assign_pointer(pa[0]->ary[id & IDR_MASK],
+ (struct idr_layer *)ptr);
pa[0]->count++;
idr_mark_full(pa, id);
}
@@ -277,12 +294,8 @@ int idr_get_new_above(struct idr *idp, void *ptr, int starting_id, int *id)
* This is a cheap hack until the IDR code can be fixed to
* return proper error values.
*/
- if (rv < 0) {
- if (rv == -1)
- return -EAGAIN;
- else /* Will be -3 */
- return -ENOSPC;
- }
+ if (rv < 0)
+ return _idr_rc_to_errno(rv);
*id = rv;
return 0;
}
@@ -312,12 +325,8 @@ int idr_get_new(struct idr *idp, void *ptr, int *id)
* This is a cheap hack until the IDR code can be fixed to
* return proper error values.
*/
- if (rv < 0) {
- if (rv == -1)
- return -EAGAIN;
- else /* Will be -3 */
- return -ENOSPC;
- }
+ if (rv < 0)
+ return _idr_rc_to_errno(rv);
*id = rv;
return 0;
}
@@ -325,7 +334,8 @@ EXPORT_SYMBOL(idr_get_new);
static void idr_remove_warning(int id)
{
- printk("idr_remove called for id=%d which is not allocated.\n", id);
+ printk(KERN_WARNING
+ "idr_remove called for id=%d which is not allocated.\n", id);
dump_stack();
}
@@ -334,6 +344,7 @@ static void sub_remove(struct idr *idp, int shift, int id)
struct idr_layer *p = idp->top;
struct idr_layer **pa[MAX_LEVEL];
struct idr_layer ***paa = &pa[0];
+ struct idr_layer *to_free;
int n;
*paa = NULL;
@@ -349,13 +360,18 @@ static void sub_remove(struct idr *idp, int shift, int id)
n = id & IDR_MASK;
if (likely(p != NULL && test_bit(n, &p->bitmap))){
__clear_bit(n, &p->bitmap);
- p->ary[n] = NULL;
+ rcu_assign_pointer(p->ary[n], NULL);
+ to_free = NULL;
while(*paa && ! --((**paa)->count)){
- free_layer(idp, **paa);
+ if (to_free)
+ free_layer(to_free);
+ to_free = **paa;
**paa-- = NULL;
}
if (!*paa)
idp->layers = 0;
+ if (to_free)
+ free_layer(to_free);
} else
idr_remove_warning(id);
}
@@ -368,22 +384,34 @@ static void sub_remove(struct idr *idp, int shift, int id)
void idr_remove(struct idr *idp, int id)
{
struct idr_layer *p;
+ struct idr_layer *to_free;
/* Mask off upper bits we don't use for the search. */
id &= MAX_ID_MASK;
sub_remove(idp, (idp->layers - 1) * IDR_BITS, id);
if (idp->top && idp->top->count == 1 && (idp->layers > 1) &&
- idp->top->ary[0]) { // We can drop a layer
-
+ idp->top->ary[0]) {
+ /*
+ * Single child at leftmost slot: we can shrink the tree.
+ * This level is not needed anymore since when layers are
+ * inserted, they are inserted at the top of the existing
+ * tree.
+ */
+ to_free = idp->top;
p = idp->top->ary[0];
- idp->top->bitmap = idp->top->count = 0;
- free_layer(idp, idp->top);
- idp->top = p;
+ rcu_assign_pointer(idp->top, p);
--idp->layers;
+ to_free->bitmap = to_free->count = 0;
+ free_layer(to_free);
}
while (idp->id_free_cnt >= IDR_FREE_MAX) {
- p = alloc_layer(idp);
+ p = get_from_free_list(idp);
+ /*
+ * Note: we don't call the rcu callback here, since the only
+ * layers that fall into the freelist are those that have been
+ * preallocated.
+ */
kmem_cache_free(idr_layer_cache, p);
}
return;
@@ -424,15 +452,13 @@ void idr_remove_all(struct idr *idp)
id += 1 << n;
while (n < fls(id)) {
- if (p) {
- memset(p, 0, sizeof *p);
- free_layer(idp, p);
- }
+ if (p)
+ free_layer(p);
n += IDR_BITS;
p = *--paa;
}
}
- idp->top = NULL;
+ rcu_assign_pointer(idp->top, NULL);
idp->layers = 0;
}
EXPORT_SYMBOL(idr_remove_all);
@@ -444,7 +470,7 @@ EXPORT_SYMBOL(idr_remove_all);
void idr_destroy(struct idr *idp)
{
while (idp->id_free_cnt) {
- struct idr_layer *p = alloc_layer(idp);
+ struct idr_layer *p = get_from_free_list(idp);
kmem_cache_free(idr_layer_cache, p);
}
}
@@ -459,7 +485,8 @@ EXPORT_SYMBOL(idr_destroy);
* return indicates that @id is not valid or you passed %NULL in
* idr_get_new().
*
- * The caller must serialize idr_find() vs idr_get_new() and idr_remove().
+ * This function can be called under rcu_read_lock(), given that the leaf
+ * pointers lifetimes are correctly managed.
*/
void *idr_find(struct idr *idp, int id)
{
@@ -467,7 +494,7 @@ void *idr_find(struct idr *idp, int id)
struct idr_layer *p;
n = idp->layers * IDR_BITS;
- p = idp->top;
+ p = rcu_dereference(idp->top);
/* Mask off upper bits we don't use for the search. */
id &= MAX_ID_MASK;
@@ -477,7 +504,7 @@ void *idr_find(struct idr *idp, int id)
while (n > 0 && p) {
n -= IDR_BITS;
- p = p->ary[(id >> n) & IDR_MASK];
+ p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
}
return((void *)p);
}
@@ -510,7 +537,7 @@ int idr_for_each(struct idr *idp,
struct idr_layer **paa = &pa[0];
n = idp->layers * IDR_BITS;
- p = idp->top;
+ p = rcu_dereference(idp->top);
max = 1 << n;
id = 0;
@@ -518,7 +545,7 @@ int idr_for_each(struct idr *idp,
while (n > 0 && p) {
n -= IDR_BITS;
*paa++ = p;
- p = p->ary[(id >> n) & IDR_MASK];
+ p = rcu_dereference(p->ary[(id >> n) & IDR_MASK]);
}
if (p) {
@@ -548,7 +575,7 @@ EXPORT_SYMBOL(idr_for_each);
* A -ENOENT return indicates that @id was not found.
* A -EINVAL return indicates that @id was not within valid constraints.
*
- * The caller must serialize vs idr_find(), idr_get_new(), and idr_remove().
+ * The caller must serialize with writers.
*/
void *idr_replace(struct idr *idp, void *ptr, int id)
{
@@ -574,13 +601,13 @@ void *idr_replace(struct idr *idp, void *ptr, int id)
return ERR_PTR(-ENOENT);
old_p = p->ary[n];
- p->ary[n] = ptr;
+ rcu_assign_pointer(p->ary[n], ptr);
return old_p;
}
EXPORT_SYMBOL(idr_replace);
-static void idr_cache_ctor(struct kmem_cache *idr_layer_cache, void *idr_layer)
+static void idr_cache_ctor(void *idr_layer)
{
memset(idr_layer, 0, sizeof(struct idr_layer));
}
@@ -694,12 +721,8 @@ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
restart:
/* get vacant slot */
t = idr_get_empty_slot(&ida->idr, idr_id, pa);
- if (t < 0) {
- if (t == -1)
- return -EAGAIN;
- else /* will be -3 */
- return -ENOSPC;
- }
+ if (t < 0)
+ return _idr_rc_to_errno(t);
if (t * IDA_BITMAP_BITS >= MAX_ID_BIT)
return -ENOSPC;
@@ -720,7 +743,8 @@ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
return -EAGAIN;
memset(bitmap, 0, sizeof(struct ida_bitmap));
- pa[0]->ary[idr_id & IDR_MASK] = (void *)bitmap;
+ rcu_assign_pointer(pa[0]->ary[idr_id & IDR_MASK],
+ (void *)bitmap);
pa[0]->count++;
}
@@ -749,7 +773,7 @@ int ida_get_new_above(struct ida *ida, int starting_id, int *p_id)
* allocation.
*/
if (ida->idr.id_free_cnt || ida->free_bitmap) {
- struct idr_layer *p = alloc_layer(&ida->idr);
+ struct idr_layer *p = get_from_free_list(&ida->idr);
if (p)
kmem_cache_free(idr_layer_cache, p);
}
diff --git a/lib/inflate.c b/lib/inflate.c
index 9762294be062..1a8e8a978128 100644
--- a/lib/inflate.c
+++ b/lib/inflate.c
@@ -230,6 +230,45 @@ STATIC const ush mask_bits[] = {
#define NEEDBITS(n) {while(k<(n)){b|=((ulg)NEXTBYTE())<<k;k+=8;}}
#define DUMPBITS(n) {b>>=(n);k-=(n);}
+#ifndef NO_INFLATE_MALLOC
+/* A trivial malloc implementation, adapted from
+ * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
+ */
+
+static unsigned long malloc_ptr;
+static int malloc_count;
+
+static void *malloc(int size)
+{
+ void *p;
+
+ if (size < 0)
+ error("Malloc error");
+ if (!malloc_ptr)
+ malloc_ptr = free_mem_ptr;
+
+ malloc_ptr = (malloc_ptr + 3) & ~3; /* Align */
+
+ p = (void *)malloc_ptr;
+ malloc_ptr += size;
+
+ if (free_mem_end_ptr && malloc_ptr >= free_mem_end_ptr)
+ error("Out of memory");
+
+ malloc_count++;
+ return p;
+}
+
+static void free(void *where)
+{
+ malloc_count--;
+ if (!malloc_count)
+ malloc_ptr = free_mem_ptr;
+}
+#else
+#define malloc(a) kmalloc(a, GFP_KERNEL)
+#define free(a) kfree(a)
+#endif
/*
Huffman code decoding is performed using a multi-level table lookup.
@@ -1045,7 +1084,6 @@ STATIC int INIT inflate(void)
int e; /* last block flag */
int r; /* result code */
unsigned h; /* maximum struct huft's malloc'ed */
- void *ptr;
/* initialize window, bit buffer */
wp = 0;
@@ -1057,12 +1095,12 @@ STATIC int INIT inflate(void)
h = 0;
do {
hufts = 0;
- gzip_mark(&ptr);
- if ((r = inflate_block(&e)) != 0) {
- gzip_release(&ptr);
- return r;
- }
- gzip_release(&ptr);
+#ifdef ARCH_HAS_DECOMP_WDOG
+ arch_decomp_wdog();
+#endif
+ r = inflate_block(&e);
+ if (r)
+ return r;
if (hufts > h)
h = hufts;
} while (!e);
diff --git a/lib/iomap.c b/lib/iomap.c
index 37a3ea4cac9f..d32229385151 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -40,8 +40,7 @@ static void bad_io_access(unsigned long port, const char *access)
static int count = 10;
if (count) {
count--;
- printk(KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
- WARN_ON(1);
+ WARN(1, KERN_ERR "Bad IO access at port %#lx (%s)\n", port, access);
}
}
diff --git a/lib/kobject.c b/lib/kobject.c
index 744401571ed7..bd732ffebc85 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -164,9 +164,8 @@ static int kobject_add_internal(struct kobject *kobj)
return -ENOENT;
if (!kobj->name || !kobj->name[0]) {
- pr_debug("kobject: (%p): attempted to be registered with empty "
+ WARN(1, "kobject: (%p): attempted to be registered with empty "
"name!\n", kobj);
- WARN_ON(1);
return -EINVAL;
}
@@ -583,12 +582,10 @@ static void kobject_release(struct kref *kref)
void kobject_put(struct kobject *kobj)
{
if (kobj) {
- if (!kobj->state_initialized) {
- printk(KERN_WARNING "kobject: '%s' (%p): is not "
+ if (!kobj->state_initialized)
+ WARN(1, KERN_WARNING "kobject: '%s' (%p): is not "
"initialized, yet kobject_put() is being "
"called.\n", kobject_name(kobj), kobj);
- WARN_ON(1);
- }
kref_put(&kobj->kref, kobject_release);
}
}
diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index 9f8d599459d1..3f914725bda8 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -285,8 +285,7 @@ int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
int len;
if (env->envp_idx >= ARRAY_SIZE(env->envp)) {
- printk(KERN_ERR "add_uevent_var: too many keys\n");
- WARN_ON(1);
+ WARN(1, KERN_ERR "add_uevent_var: too many keys\n");
return -ENOMEM;
}
@@ -297,8 +296,7 @@ int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...)
va_end(args);
if (len >= (sizeof(env->buf) - env->buflen)) {
- printk(KERN_ERR "add_uevent_var: buffer size too small\n");
- WARN_ON(1);
+ WARN(1, KERN_ERR "add_uevent_var: buffer size too small\n");
return -ENOMEM;
}
diff --git a/lib/list_debug.c b/lib/list_debug.c
index 4350ba9655bd..1a39f4e3ae1f 100644
--- a/lib/list_debug.c
+++ b/lib/list_debug.c
@@ -20,18 +20,14 @@ void __list_add(struct list_head *new,
struct list_head *prev,
struct list_head *next)
{
- if (unlikely(next->prev != prev)) {
- printk(KERN_ERR "list_add corruption. next->prev should be "
- "prev (%p), but was %p. (next=%p).\n",
- prev, next->prev, next);
- BUG();
- }
- if (unlikely(prev->next != next)) {
- printk(KERN_ERR "list_add corruption. prev->next should be "
- "next (%p), but was %p. (prev=%p).\n",
- next, prev->next, prev);
- BUG();
- }
+ WARN(next->prev != prev,
+ "list_add corruption. next->prev should be "
+ "prev (%p), but was %p. (next=%p).\n",
+ prev, next->prev, next);
+ WARN(prev->next != next,
+ "list_add corruption. prev->next should be "
+ "next (%p), but was %p. (prev=%p).\n",
+ next, prev->next, prev);
next->prev = new;
new->next = next;
new->prev = prev;
@@ -40,20 +36,6 @@ void __list_add(struct list_head *new,
EXPORT_SYMBOL(__list_add);
/**
- * list_add - add a new entry
- * @new: new entry to be added
- * @head: list head to add it after
- *
- * Insert a new entry after the specified head.
- * This is good for implementing stacks.
- */
-void list_add(struct list_head *new, struct list_head *head)
-{
- __list_add(new, head, head->next);
-}
-EXPORT_SYMBOL(list_add);
-
-/**
* list_del - deletes entry from list.
* @entry: the element to delete from the list.
* Note: list_empty on entry does not return true after this, the entry is
@@ -61,16 +43,12 @@ EXPORT_SYMBOL(list_add);
*/
void list_del(struct list_head *entry)
{
- if (unlikely(entry->prev->next != entry)) {
- printk(KERN_ERR "list_del corruption. prev->next should be %p, "
- "but was %p\n", entry, entry->prev->next);
- BUG();
- }
- if (unlikely(entry->next->prev != entry)) {
- printk(KERN_ERR "list_del corruption. next->prev should be %p, "
- "but was %p\n", entry, entry->next->prev);
- BUG();
- }
+ WARN(entry->prev->next != entry,
+ "list_del corruption. prev->next should be %p, "
+ "but was %p\n", entry, entry->prev->next);
+ WARN(entry->next->prev != entry,
+ "list_del corruption. next->prev should be %p, "
+ "but was %p\n", entry, entry->next->prev);
__list_del(entry->prev, entry->next);
entry->next = LIST_POISON1;
entry->prev = LIST_POISON2;
diff --git a/lib/lzo/lzo1x_decompress.c b/lib/lzo/lzo1x_decompress.c
index 77f0f9b775a9..5dc6b29c1575 100644
--- a/lib/lzo/lzo1x_decompress.c
+++ b/lib/lzo/lzo1x_decompress.c
@@ -138,8 +138,7 @@ match:
t += 31 + *ip++;
}
m_pos = op - 1;
- m_pos -= le16_to_cpu(get_unaligned(
- (const unsigned short *)ip)) >> 2;
+ m_pos -= get_unaligned_le16(ip) >> 2;
ip += 2;
} else if (t >= 16) {
m_pos = op;
@@ -157,8 +156,7 @@ match:
}
t += 7 + *ip++;
}
- m_pos -= le16_to_cpu(get_unaligned(
- (const unsigned short *)ip)) >> 2;
+ m_pos -= get_unaligned_le16(ip) >> 2;
ip += 2;
if (m_pos == op)
goto eof_found;
diff --git a/lib/plist.c b/lib/plist.c
index 3074a02272f3..d6c64a824e1d 100644
--- a/lib/plist.c
+++ b/lib/plist.c
@@ -31,12 +31,13 @@
static void plist_check_prev_next(struct list_head *t, struct list_head *p,
struct list_head *n)
{
- if (n->prev != p || p->next != n) {
- printk("top: %p, n: %p, p: %p\n", t, t->next, t->prev);
- printk("prev: %p, n: %p, p: %p\n", p, p->next, p->prev);
- printk("next: %p, n: %p, p: %p\n", n, n->next, n->prev);
- WARN_ON(1);
- }
+ WARN(n->prev != p || p->next != n,
+ "top: %p, n: %p, p: %p\n"
+ "prev: %p, n: %p, p: %p\n"
+ "next: %p, n: %p, p: %p\n",
+ t, t->next, t->prev,
+ p, p->next, p->prev,
+ n, n->next, n->prev);
}
static void plist_check_list(struct list_head *top)
diff --git a/lib/radix-tree.c b/lib/radix-tree.c
index 56ec21a7f73d..be86b32bc874 100644
--- a/lib/radix-tree.c
+++ b/lib/radix-tree.c
@@ -359,18 +359,17 @@ EXPORT_SYMBOL(radix_tree_insert);
* Returns: the slot corresponding to the position @index in the
* radix tree @root. This is useful for update-if-exists operations.
*
- * This function cannot be called under rcu_read_lock, it must be
- * excluded from writers, as must the returned slot for subsequent
- * use by radix_tree_deref_slot() and radix_tree_replace slot.
- * Caller must hold tree write locked across slot lookup and
- * replace.
+ * This function can be called under rcu_read_lock iff the slot is not
+ * modified by radix_tree_replace_slot, otherwise it must be called
+ * exclusive from other writers. Any dereference of the slot must be done
+ * using radix_tree_deref_slot.
*/
void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
{
unsigned int height, shift;
struct radix_tree_node *node, **slot;
- node = root->rnode;
+ node = rcu_dereference(root->rnode);
if (node == NULL)
return NULL;
@@ -390,7 +389,7 @@ void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
do {
slot = (struct radix_tree_node **)
(node->slots + ((index>>shift) & RADIX_TREE_MAP_MASK));
- node = *slot;
+ node = rcu_dereference(*slot);
if (node == NULL)
return NULL;
@@ -667,7 +666,7 @@ unsigned long radix_tree_next_hole(struct radix_tree_root *root,
EXPORT_SYMBOL(radix_tree_next_hole);
static unsigned int
-__lookup(struct radix_tree_node *slot, void **results, unsigned long index,
+__lookup(struct radix_tree_node *slot, void ***results, unsigned long index,
unsigned int max_items, unsigned long *next_index)
{
unsigned int nr_found = 0;
@@ -701,11 +700,9 @@ __lookup(struct radix_tree_node *slot, void **results, unsigned long index,
/* Bottom level: grab some items */
for (i = index & RADIX_TREE_MAP_MASK; i < RADIX_TREE_MAP_SIZE; i++) {
- struct radix_tree_node *node;
index++;
- node = slot->slots[i];
- if (node) {
- results[nr_found++] = rcu_dereference(node);
+ if (slot->slots[i]) {
+ results[nr_found++] = &(slot->slots[i]);
if (nr_found == max_items)
goto out;
}
@@ -759,13 +756,22 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
ret = 0;
while (ret < max_items) {
- unsigned int nr_found;
+ unsigned int nr_found, slots_found, i;
unsigned long next_index; /* Index of next search */
if (cur_index > max_index)
break;
- nr_found = __lookup(node, results + ret, cur_index,
+ slots_found = __lookup(node, (void ***)results + ret, cur_index,
max_items - ret, &next_index);
+ nr_found = 0;
+ for (i = 0; i < slots_found; i++) {
+ struct radix_tree_node *slot;
+ slot = *(((void ***)results)[ret + i]);
+ if (!slot)
+ continue;
+ results[ret + nr_found] = rcu_dereference(slot);
+ nr_found++;
+ }
ret += nr_found;
if (next_index == 0)
break;
@@ -776,12 +782,71 @@ radix_tree_gang_lookup(struct radix_tree_root *root, void **results,
}
EXPORT_SYMBOL(radix_tree_gang_lookup);
+/**
+ * radix_tree_gang_lookup_slot - perform multiple slot lookup on radix tree
+ * @root: radix tree root
+ * @results: where the results of the lookup are placed
+ * @first_index: start the lookup from this key
+ * @max_items: place up to this many items at *results
+ *
+ * Performs an index-ascending scan of the tree for present items. Places
+ * their slots at *@results and returns the number of items which were
+ * placed at *@results.
+ *
+ * The implementation is naive.
+ *
+ * Like radix_tree_gang_lookup as far as RCU and locking goes. Slots must
+ * be dereferenced with radix_tree_deref_slot, and if using only RCU
+ * protection, radix_tree_deref_slot may fail requiring a retry.
+ */
+unsigned int
+radix_tree_gang_lookup_slot(struct radix_tree_root *root, void ***results,
+ unsigned long first_index, unsigned int max_items)
+{
+ unsigned long max_index;
+ struct radix_tree_node *node;
+ unsigned long cur_index = first_index;
+ unsigned int ret;
+
+ node = rcu_dereference(root->rnode);
+ if (!node)
+ return 0;
+
+ if (!radix_tree_is_indirect_ptr(node)) {
+ if (first_index > 0)
+ return 0;
+ results[0] = (void **)&root->rnode;
+ return 1;
+ }
+ node = radix_tree_indirect_to_ptr(node);
+
+ max_index = radix_tree_maxindex(node->height);
+
+ ret = 0;
+ while (ret < max_items) {
+ unsigned int slots_found;
+ unsigned long next_index; /* Index of next search */
+
+ if (cur_index > max_index)
+ break;
+ slots_found = __lookup(node, results + ret, cur_index,
+ max_items - ret, &next_index);
+ ret += slots_found;
+ if (next_index == 0)
+ break;
+ cur_index = next_index;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(radix_tree_gang_lookup_slot);
+
/*
* FIXME: the two tag_get()s here should use find_next_bit() instead of
* open-coding the search.
*/
static unsigned int
-__lookup_tag(struct radix_tree_node *slot, void **results, unsigned long index,
+__lookup_tag(struct radix_tree_node *slot, void ***results, unsigned long index,
unsigned int max_items, unsigned long *next_index, unsigned int tag)
{
unsigned int nr_found = 0;
@@ -811,11 +876,9 @@ __lookup_tag(struct radix_tree_node *slot, void **results, unsigned long index,
unsigned long j = index & RADIX_TREE_MAP_MASK;
for ( ; j < RADIX_TREE_MAP_SIZE; j++) {
- struct radix_tree_node *node;
index++;
if (!tag_get(slot, tag, j))
continue;
- node = slot->slots[j];
/*
* Even though the tag was found set, we need to
* recheck that we have a non-NULL node, because
@@ -826,9 +889,8 @@ __lookup_tag(struct radix_tree_node *slot, void **results, unsigned long index,
* lookup ->slots[x] without a lock (ie. can't
* rely on its value remaining the same).
*/
- if (node) {
- node = rcu_dereference(node);
- results[nr_found++] = node;
+ if (slot->slots[j]) {
+ results[nr_found++] = &(slot->slots[j]);
if (nr_found == max_items)
goto out;
}
@@ -887,13 +949,22 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results,
ret = 0;
while (ret < max_items) {
- unsigned int nr_found;
+ unsigned int nr_found, slots_found, i;
unsigned long next_index; /* Index of next search */
if (cur_index > max_index)
break;
- nr_found = __lookup_tag(node, results + ret, cur_index,
- max_items - ret, &next_index, tag);
+ slots_found = __lookup_tag(node, (void ***)results + ret,
+ cur_index, max_items - ret, &next_index, tag);
+ nr_found = 0;
+ for (i = 0; i < slots_found; i++) {
+ struct radix_tree_node *slot;
+ slot = *(((void ***)results)[ret + i]);
+ if (!slot)
+ continue;
+ results[ret + nr_found] = rcu_dereference(slot);
+ nr_found++;
+ }
ret += nr_found;
if (next_index == 0)
break;
@@ -905,6 +976,67 @@ radix_tree_gang_lookup_tag(struct radix_tree_root *root, void **results,
EXPORT_SYMBOL(radix_tree_gang_lookup_tag);
/**
+ * radix_tree_gang_lookup_tag_slot - perform multiple slot lookup on a
+ * radix tree based on a tag
+ * @root: radix tree root
+ * @results: where the results of the lookup are placed
+ * @first_index: start the lookup from this key
+ * @max_items: place up to this many items at *results
+ * @tag: the tag index (< RADIX_TREE_MAX_TAGS)
+ *
+ * Performs an index-ascending scan of the tree for present items which
+ * have the tag indexed by @tag set. Places the slots at *@results and
+ * returns the number of slots which were placed at *@results.
+ */
+unsigned int
+radix_tree_gang_lookup_tag_slot(struct radix_tree_root *root, void ***results,
+ unsigned long first_index, unsigned int max_items,
+ unsigned int tag)
+{
+ struct radix_tree_node *node;
+ unsigned long max_index;
+ unsigned long cur_index = first_index;
+ unsigned int ret;
+
+ /* check the root's tag bit */
+ if (!root_tag_get(root, tag))
+ return 0;
+
+ node = rcu_dereference(root->rnode);
+ if (!node)
+ return 0;
+
+ if (!radix_tree_is_indirect_ptr(node)) {
+ if (first_index > 0)
+ return 0;
+ results[0] = (void **)&root->rnode;
+ return 1;
+ }
+ node = radix_tree_indirect_to_ptr(node);
+
+ max_index = radix_tree_maxindex(node->height);
+
+ ret = 0;
+ while (ret < max_items) {
+ unsigned int slots_found;
+ unsigned long next_index; /* Index of next search */
+
+ if (cur_index > max_index)
+ break;
+ slots_found = __lookup_tag(node, results + ret,
+ cur_index, max_items - ret, &next_index, tag);
+ ret += slots_found;
+ if (next_index == 0)
+ break;
+ cur_index = next_index;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(radix_tree_gang_lookup_tag_slot);
+
+
+/**
* radix_tree_shrink - shrink height of a radix tree to minimal
* @root radix tree root
*/
@@ -1051,7 +1183,7 @@ int radix_tree_tagged(struct radix_tree_root *root, unsigned int tag)
EXPORT_SYMBOL(radix_tree_tagged);
static void
-radix_tree_node_ctor(struct kmem_cache *cachep, void *node)
+radix_tree_node_ctor(void *node)
{
memset(node, 0, sizeof(struct radix_tree_node));
}
diff --git a/lib/ratelimit.c b/lib/ratelimit.c
index 485e3040dcd4..35136671b215 100644
--- a/lib/ratelimit.c
+++ b/lib/ratelimit.c
@@ -3,6 +3,9 @@
*
* Isolated from kernel/printk.c by Dave Young <hidave.darkstar@gmail.com>
*
+ * 2008-05-01 rewrite the function and use a ratelimit_state data struct as
+ * parameter. Now every user can use their own standalone ratelimit_state.
+ *
* This file is released under the GPLv2.
*
*/
@@ -11,41 +14,43 @@
#include <linux/jiffies.h>
#include <linux/module.h>
+static DEFINE_SPINLOCK(ratelimit_lock);
+static unsigned long flags;
+
/*
* __ratelimit - rate limiting
- * @ratelimit_jiffies: minimum time in jiffies between two callbacks
- * @ratelimit_burst: number of callbacks we do before ratelimiting
+ * @rs: ratelimit_state data
*
- * This enforces a rate limit: not more than @ratelimit_burst callbacks
- * in every ratelimit_jiffies
+ * This enforces a rate limit: not more than @rs->ratelimit_burst callbacks
+ * in every @rs->ratelimit_jiffies
*/
-int __ratelimit(int ratelimit_jiffies, int ratelimit_burst)
+int __ratelimit(struct ratelimit_state *rs)
{
- static DEFINE_SPINLOCK(ratelimit_lock);
- static unsigned toks = 10 * 5 * HZ;
- static unsigned long last_msg;
- static int missed;
- unsigned long flags;
- unsigned long now = jiffies;
+ if (!rs->interval)
+ return 1;
spin_lock_irqsave(&ratelimit_lock, flags);
- toks += now - last_msg;
- last_msg = now;
- if (toks > (ratelimit_burst * ratelimit_jiffies))
- toks = ratelimit_burst * ratelimit_jiffies;
- if (toks >= ratelimit_jiffies) {
- int lost = missed;
+ if (!rs->begin)
+ rs->begin = jiffies;
- missed = 0;
- toks -= ratelimit_jiffies;
- spin_unlock_irqrestore(&ratelimit_lock, flags);
- if (lost)
- printk(KERN_WARNING "%s: %d messages suppressed\n",
- __func__, lost);
- return 1;
+ if (time_is_before_jiffies(rs->begin + rs->interval)) {
+ if (rs->missed)
+ printk(KERN_WARNING "%s: %d callbacks suppressed\n",
+ __func__, rs->missed);
+ rs->begin = 0;
+ rs->printed = 0;
+ rs->missed = 0;
}
- missed++;
+ if (rs->burst && rs->burst > rs->printed)
+ goto print;
+
+ rs->missed++;
spin_unlock_irqrestore(&ratelimit_lock, flags);
return 0;
+
+print:
+ rs->printed++;
+ spin_unlock_irqrestore(&ratelimit_lock, flags);
+ return 1;
}
EXPORT_SYMBOL(__ratelimit);
diff --git a/lib/show_mem.c b/lib/show_mem.c
new file mode 100644
index 000000000000..238e72a18ce1
--- /dev/null
+++ b/lib/show_mem.c
@@ -0,0 +1,63 @@
+/*
+ * Generic show_mem() implementation
+ *
+ * Copyright (C) 2008 Johannes Weiner <hannes@saeurebad.de>
+ * All code subject to the GPL version 2.
+ */
+
+#include <linux/mm.h>
+#include <linux/nmi.h>
+#include <linux/quicklist.h>
+
+void show_mem(void)
+{
+ pg_data_t *pgdat;
+ unsigned long total = 0, reserved = 0, shared = 0,
+ nonshared = 0, highmem = 0;
+
+ printk(KERN_INFO "Mem-Info:\n");
+ show_free_areas();
+
+ for_each_online_pgdat(pgdat) {
+ unsigned long i, flags;
+
+ pgdat_resize_lock(pgdat, &flags);
+ for (i = 0; i < pgdat->node_spanned_pages; i++) {
+ struct page *page;
+ unsigned long pfn = pgdat->node_start_pfn + i;
+
+ if (unlikely(!(i % MAX_ORDER_NR_PAGES)))
+ touch_nmi_watchdog();
+
+ if (!pfn_valid(pfn))
+ continue;
+
+ page = pfn_to_page(pfn);
+
+ if (PageHighMem(page))
+ highmem++;
+
+ if (PageReserved(page))
+ reserved++;
+ else if (page_count(page) == 1)
+ nonshared++;
+ else if (page_count(page) > 1)
+ shared += page_count(page) - 1;
+
+ total++;
+ }
+ pgdat_resize_unlock(pgdat, &flags);
+ }
+
+ printk(KERN_INFO "%lu pages RAM\n", total);
+#ifdef CONFIG_HIGHMEM
+ printk(KERN_INFO "%lu pages HighMem\n", highmem);
+#endif
+ printk(KERN_INFO "%lu pages reserved\n", reserved);
+ printk(KERN_INFO "%lu pages shared\n", shared);
+ printk(KERN_INFO "%lu pages non-shared\n", nonshared);
+#ifdef CONFIG_QUICKLIST
+ printk(KERN_INFO "%lu pages in pagetable cache\n",
+ quicklist_total_size());
+#endif
+}
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index d568894df8cc..977edbdbc1de 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -492,7 +492,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
*/
dma_addr_t handle;
handle = swiotlb_map_single(NULL, NULL, size, DMA_FROM_DEVICE);
- if (swiotlb_dma_mapping_error(handle))
+ if (swiotlb_dma_mapping_error(hwdev, handle))
return NULL;
ret = bus_to_virt(handle);
@@ -824,7 +824,7 @@ swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
}
int
-swiotlb_dma_mapping_error(dma_addr_t dma_addr)
+swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
{
return (dma_addr == virt_to_bus(io_tlb_overflow_buffer));
}
diff --git a/lib/syscall.c b/lib/syscall.c
new file mode 100644
index 000000000000..a4f7067f72fa
--- /dev/null
+++ b/lib/syscall.c
@@ -0,0 +1,75 @@
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <asm/syscall.h>
+
+static int collect_syscall(struct task_struct *target, long *callno,
+ unsigned long args[6], unsigned int maxargs,
+ unsigned long *sp, unsigned long *pc)
+{
+ struct pt_regs *regs = task_pt_regs(target);
+ if (unlikely(!regs))
+ return -EAGAIN;
+
+ *sp = user_stack_pointer(regs);
+ *pc = instruction_pointer(regs);
+
+ *callno = syscall_get_nr(target, regs);
+ if (*callno != -1L && maxargs > 0)
+ syscall_get_arguments(target, regs, 0, maxargs, args);
+
+ return 0;
+}
+
+/**
+ * task_current_syscall - Discover what a blocked task is doing.
+ * @target: thread to examine
+ * @callno: filled with system call number or -1
+ * @args: filled with @maxargs system call arguments
+ * @maxargs: number of elements in @args to fill
+ * @sp: filled with user stack pointer
+ * @pc: filled with user PC
+ *
+ * If @target is blocked in a system call, returns zero with *@callno
+ * set to the the call's number and @args filled in with its arguments.
+ * Registers not used for system call arguments may not be available and
+ * it is not kosher to use &struct user_regset calls while the system
+ * call is still in progress. Note we may get this result if @target
+ * has finished its system call but not yet returned to user mode, such
+ * as when it's stopped for signal handling or syscall exit tracing.
+ *
+ * If @target is blocked in the kernel during a fault or exception,
+ * returns zero with *@callno set to -1 and does not fill in @args.
+ * If so, it's now safe to examine @target using &struct user_regset
+ * get() calls as long as we're sure @target won't return to user mode.
+ *
+ * Returns -%EAGAIN if @target does not remain blocked.
+ *
+ * Returns -%EINVAL if @maxargs is too large (maximum is six).
+ */
+int task_current_syscall(struct task_struct *target, long *callno,
+ unsigned long args[6], unsigned int maxargs,
+ unsigned long *sp, unsigned long *pc)
+{
+ long state;
+ unsigned long ncsw;
+
+ if (unlikely(maxargs > 6))
+ return -EINVAL;
+
+ if (target == current)
+ return collect_syscall(target, callno, args, maxargs, sp, pc);
+
+ state = target->state;
+ if (unlikely(!state))
+ return -EAGAIN;
+
+ ncsw = wait_task_inactive(target, state);
+ if (unlikely(!ncsw) ||
+ unlikely(collect_syscall(target, callno, args, maxargs, sp, pc)) ||
+ unlikely(wait_task_inactive(target, state) != ncsw))
+ return -EAGAIN;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(task_current_syscall);