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-rw-r--r--lib/Kconfig10
-rw-r--r--lib/Kconfig.debug19
-rw-r--r--lib/Makefile1
-rw-r--r--lib/debugobjects.c20
-rw-r--r--lib/dynamic_debug.c2
-rw-r--r--lib/earlycpio.c27
-rw-r--r--lib/kobject.c22
-rw-r--r--lib/lockref.c128
-rw-r--r--lib/lz4/lz4_compress.c4
-rw-r--r--lib/lz4/lz4_decompress.c6
-rw-r--r--lib/lz4/lz4hc_compress.c4
11 files changed, 213 insertions, 30 deletions
diff --git a/lib/Kconfig b/lib/Kconfig
index 71d9f81f6eed..65561716c16c 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -48,6 +48,16 @@ config STMP_DEVICE
config PERCPU_RWSEM
boolean
+config ARCH_USE_CMPXCHG_LOCKREF
+ bool
+
+config CMPXCHG_LOCKREF
+ def_bool y if ARCH_USE_CMPXCHG_LOCKREF
+ depends on SMP
+ depends on !GENERIC_LOCKBREAK
+ depends on !DEBUG_SPINLOCK
+ depends on !DEBUG_LOCK_ALLOC
+
config CRC_CCITT
tristate "CRC-CCITT functions"
help
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 1501aa553221..444e1c12fea9 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -981,6 +981,25 @@ config DEBUG_KOBJECT
If you say Y here, some extra kobject debugging messages will be sent
to the syslog.
+config DEBUG_KOBJECT_RELEASE
+ bool "kobject release debugging"
+ depends on DEBUG_KERNEL
+ help
+ kobjects are reference counted objects. This means that their
+ last reference count put is not predictable, and the kobject can
+ live on past the point at which a driver decides to drop it's
+ initial reference to the kobject gained on allocation. An
+ example of this would be a struct device which has just been
+ unregistered.
+
+ However, some buggy drivers assume that after such an operation,
+ the memory backing the kobject can be immediately freed. This
+ goes completely against the principles of a refcounted object.
+
+ If you say Y here, the kernel will delay the release of kobjects
+ on the last reference count to improve the visibility of this
+ kind of kobject release bug.
+
config HAVE_DEBUG_BUGVERBOSE
bool
diff --git a/lib/Makefile b/lib/Makefile
index 7baccfd8a4e9..f2cb3082697c 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -20,6 +20,7 @@ lib-$(CONFIG_MMU) += ioremap.o
lib-$(CONFIG_SMP) += cpumask.o
lib-y += kobject.o klist.o
+obj-y += lockref.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 \
diff --git a/lib/debugobjects.c b/lib/debugobjects.c
index 37061ede8b81..bf2c8b1043d8 100644
--- a/lib/debugobjects.c
+++ b/lib/debugobjects.c
@@ -381,19 +381,21 @@ void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
* debug_object_activate - debug checks when an object is activated
* @addr: address of the object
* @descr: pointer to an object specific debug description structure
+ * Returns 0 for success, -EINVAL for check failed.
*/
-void debug_object_activate(void *addr, struct debug_obj_descr *descr)
+int debug_object_activate(void *addr, struct debug_obj_descr *descr)
{
enum debug_obj_state state;
struct debug_bucket *db;
struct debug_obj *obj;
unsigned long flags;
+ int ret;
struct debug_obj o = { .object = addr,
.state = ODEBUG_STATE_NOTAVAILABLE,
.descr = descr };
if (!debug_objects_enabled)
- return;
+ return 0;
db = get_bucket((unsigned long) addr);
@@ -405,23 +407,26 @@ void debug_object_activate(void *addr, struct debug_obj_descr *descr)
case ODEBUG_STATE_INIT:
case ODEBUG_STATE_INACTIVE:
obj->state = ODEBUG_STATE_ACTIVE;
+ ret = 0;
break;
case ODEBUG_STATE_ACTIVE:
debug_print_object(obj, "activate");
state = obj->state;
raw_spin_unlock_irqrestore(&db->lock, flags);
- debug_object_fixup(descr->fixup_activate, addr, state);
- return;
+ ret = debug_object_fixup(descr->fixup_activate, addr, state);
+ return ret ? -EINVAL : 0;
case ODEBUG_STATE_DESTROYED:
debug_print_object(obj, "activate");
+ ret = -EINVAL;
break;
default:
+ ret = 0;
break;
}
raw_spin_unlock_irqrestore(&db->lock, flags);
- return;
+ return ret;
}
raw_spin_unlock_irqrestore(&db->lock, flags);
@@ -431,8 +436,11 @@ void debug_object_activate(void *addr, struct debug_obj_descr *descr)
* true or not.
*/
if (debug_object_fixup(descr->fixup_activate, addr,
- ODEBUG_STATE_NOTAVAILABLE))
+ ODEBUG_STATE_NOTAVAILABLE)) {
debug_print_object(&o, "activate");
+ return -EINVAL;
+ }
+ return 0;
}
/**
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 99fec3ae405a..c37aeacd7651 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -309,7 +309,7 @@ static int ddebug_parse_query(char *words[], int nwords,
struct ddebug_query *query, const char *modname)
{
unsigned int i;
- int rc;
+ int rc = 0;
/* check we have an even number of words */
if (nwords % 2 != 0) {
diff --git a/lib/earlycpio.c b/lib/earlycpio.c
index 7aa7ce250c94..3eb3e4722b8e 100644
--- a/lib/earlycpio.c
+++ b/lib/earlycpio.c
@@ -49,22 +49,23 @@ enum cpio_fields {
/**
* cpio_data find_cpio_data - Search for files in an uncompressed cpio
- * @path: The directory to search for, including a slash at the end
- * @data: Pointer to the the cpio archive or a header inside
- * @len: Remaining length of the cpio based on data pointer
- * @offset: When a matching file is found, this is the offset to the
- * beginning of the cpio. It can be used to iterate through
- * the cpio to find all files inside of a directory path
+ * @path: The directory to search for, including a slash at the end
+ * @data: Pointer to the the cpio archive or a header inside
+ * @len: Remaining length of the cpio based on data pointer
+ * @nextoff: When a matching file is found, this is the offset from the
+ * beginning of the cpio to the beginning of the next file, not the
+ * matching file itself. It can be used to iterate through the cpio
+ * to find all files inside of a directory path.
*
- * @return: struct cpio_data containing the address, length and
- * filename (with the directory path cut off) of the found file.
- * If you search for a filename and not for files in a directory,
- * pass the absolute path of the filename in the cpio and make sure
- * the match returned an empty filename string.
+ * @return: struct cpio_data containing the address, length and
+ * filename (with the directory path cut off) of the found file.
+ * If you search for a filename and not for files in a directory,
+ * pass the absolute path of the filename in the cpio and make sure
+ * the match returned an empty filename string.
*/
struct cpio_data find_cpio_data(const char *path, void *data,
- size_t len, long *offset)
+ size_t len, long *nextoff)
{
const size_t cpio_header_len = 8*C_NFIELDS - 2;
struct cpio_data cd = { NULL, 0, "" };
@@ -124,7 +125,7 @@ struct cpio_data find_cpio_data(const char *path, void *data,
if ((ch[C_MODE] & 0170000) == 0100000 &&
ch[C_NAMESIZE] >= mypathsize &&
!memcmp(p, path, mypathsize)) {
- *offset = (long)nptr - (long)data;
+ *nextoff = (long)nptr - (long)data;
if (ch[C_NAMESIZE] - mypathsize >= MAX_CPIO_FILE_NAME) {
pr_warn(
"File %s exceeding MAX_CPIO_FILE_NAME [%d]\n",
diff --git a/lib/kobject.c b/lib/kobject.c
index 4a1f33d43548..1d46c151a4ae 100644
--- a/lib/kobject.c
+++ b/lib/kobject.c
@@ -545,8 +545,8 @@ static void kobject_cleanup(struct kobject *kobj)
struct kobj_type *t = get_ktype(kobj);
const char *name = kobj->name;
- pr_debug("kobject: '%s' (%p): %s\n",
- kobject_name(kobj), kobj, __func__);
+ pr_debug("kobject: '%s' (%p): %s, parent %p\n",
+ kobject_name(kobj), kobj, __func__, kobj->parent);
if (t && !t->release)
pr_debug("kobject: '%s' (%p): does not have a release() "
@@ -580,9 +580,25 @@ static void kobject_cleanup(struct kobject *kobj)
}
}
+#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
+static void kobject_delayed_cleanup(struct work_struct *work)
+{
+ kobject_cleanup(container_of(to_delayed_work(work),
+ struct kobject, release));
+}
+#endif
+
static void kobject_release(struct kref *kref)
{
- kobject_cleanup(container_of(kref, struct kobject, kref));
+ struct kobject *kobj = container_of(kref, struct kobject, kref);
+#ifdef CONFIG_DEBUG_KOBJECT_RELEASE
+ pr_debug("kobject: '%s' (%p): %s, parent %p (delayed)\n",
+ kobject_name(kobj), kobj, __func__, kobj->parent);
+ INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
+ schedule_delayed_work(&kobj->release, HZ);
+#else
+ kobject_cleanup(kobj);
+#endif
}
/**
diff --git a/lib/lockref.c b/lib/lockref.c
new file mode 100644
index 000000000000..9d76f404ce9a
--- /dev/null
+++ b/lib/lockref.c
@@ -0,0 +1,128 @@
+#include <linux/export.h>
+#include <linux/lockref.h>
+
+#ifdef CONFIG_CMPXCHG_LOCKREF
+
+/*
+ * Note that the "cmpxchg()" reloads the "old" value for the
+ * failure case.
+ */
+#define CMPXCHG_LOOP(CODE, SUCCESS) do { \
+ struct lockref old; \
+ BUILD_BUG_ON(sizeof(old) != 8); \
+ old.lock_count = ACCESS_ONCE(lockref->lock_count); \
+ while (likely(arch_spin_value_unlocked(old.lock.rlock.raw_lock))) { \
+ struct lockref new = old, prev = old; \
+ CODE \
+ old.lock_count = cmpxchg(&lockref->lock_count, \
+ old.lock_count, new.lock_count); \
+ if (likely(old.lock_count == prev.lock_count)) { \
+ SUCCESS; \
+ } \
+ cpu_relax(); \
+ } \
+} while (0)
+
+#else
+
+#define CMPXCHG_LOOP(CODE, SUCCESS) do { } while (0)
+
+#endif
+
+/**
+ * lockref_get - Increments reference count unconditionally
+ * @lockcnt: pointer to lockref structure
+ *
+ * This operation is only valid if you already hold a reference
+ * to the object, so you know the count cannot be zero.
+ */
+void lockref_get(struct lockref *lockref)
+{
+ CMPXCHG_LOOP(
+ new.count++;
+ ,
+ return;
+ );
+
+ spin_lock(&lockref->lock);
+ lockref->count++;
+ spin_unlock(&lockref->lock);
+}
+EXPORT_SYMBOL(lockref_get);
+
+/**
+ * lockref_get_not_zero - Increments count unless the count is 0
+ * @lockcnt: pointer to lockref structure
+ * Return: 1 if count updated successfully or 0 if count was zero
+ */
+int lockref_get_not_zero(struct lockref *lockref)
+{
+ int retval;
+
+ CMPXCHG_LOOP(
+ new.count++;
+ if (!old.count)
+ return 0;
+ ,
+ return 1;
+ );
+
+ spin_lock(&lockref->lock);
+ retval = 0;
+ if (lockref->count) {
+ lockref->count++;
+ retval = 1;
+ }
+ spin_unlock(&lockref->lock);
+ return retval;
+}
+EXPORT_SYMBOL(lockref_get_not_zero);
+
+/**
+ * lockref_get_or_lock - Increments count unless the count is 0
+ * @lockcnt: pointer to lockref structure
+ * Return: 1 if count updated successfully or 0 if count was zero
+ * and we got the lock instead.
+ */
+int lockref_get_or_lock(struct lockref *lockref)
+{
+ CMPXCHG_LOOP(
+ new.count++;
+ if (!old.count)
+ break;
+ ,
+ return 1;
+ );
+
+ spin_lock(&lockref->lock);
+ if (!lockref->count)
+ return 0;
+ lockref->count++;
+ spin_unlock(&lockref->lock);
+ return 1;
+}
+EXPORT_SYMBOL(lockref_get_or_lock);
+
+/**
+ * lockref_put_or_lock - decrements count unless count <= 1 before decrement
+ * @lockcnt: pointer to lockref structure
+ * Return: 1 if count updated successfully or 0 if count <= 1 and lock taken
+ */
+int lockref_put_or_lock(struct lockref *lockref)
+{
+ CMPXCHG_LOOP(
+ new.count--;
+ if (old.count <= 1)
+ break;
+ ,
+ return 1;
+ );
+
+ spin_lock(&lockref->lock);
+ if (lockref->count <= 1)
+ return 0;
+ lockref->count--;
+ spin_unlock(&lockref->lock);
+ return 1;
+}
+EXPORT_SYMBOL(lockref_put_or_lock);
diff --git a/lib/lz4/lz4_compress.c b/lib/lz4/lz4_compress.c
index fd94058bd7f9..28321d8f75ef 100644
--- a/lib/lz4/lz4_compress.c
+++ b/lib/lz4/lz4_compress.c
@@ -437,7 +437,7 @@ int lz4_compress(const unsigned char *src, size_t src_len,
exit:
return ret;
}
-EXPORT_SYMBOL_GPL(lz4_compress);
+EXPORT_SYMBOL(lz4_compress);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("LZ4 compressor");
diff --git a/lib/lz4/lz4_decompress.c b/lib/lz4/lz4_decompress.c
index d3414eae73a1..411be80ddb46 100644
--- a/lib/lz4/lz4_decompress.c
+++ b/lib/lz4/lz4_decompress.c
@@ -299,7 +299,7 @@ exit_0:
return ret;
}
#ifndef STATIC
-EXPORT_SYMBOL_GPL(lz4_decompress);
+EXPORT_SYMBOL(lz4_decompress);
#endif
int lz4_decompress_unknownoutputsize(const char *src, size_t src_len,
@@ -319,8 +319,8 @@ exit_0:
return ret;
}
#ifndef STATIC
-EXPORT_SYMBOL_GPL(lz4_decompress_unknownoutputsize);
+EXPORT_SYMBOL(lz4_decompress_unknownoutputsize);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("LZ4 Decompressor");
#endif
diff --git a/lib/lz4/lz4hc_compress.c b/lib/lz4/lz4hc_compress.c
index eb1a74f5e368..f344f76b6559 100644
--- a/lib/lz4/lz4hc_compress.c
+++ b/lib/lz4/lz4hc_compress.c
@@ -533,7 +533,7 @@ int lz4hc_compress(const unsigned char *src, size_t src_len,
exit:
return ret;
}
-EXPORT_SYMBOL_GPL(lz4hc_compress);
+EXPORT_SYMBOL(lz4hc_compress);
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("LZ4HC compressor");
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-25 16:19:07 +0300