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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/dump_stack.c4
-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/swiotlb.c8
-rw-r--r--lib/vsprintf.c82
11 files changed, 294 insertions, 29 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/dump_stack.c b/lib/dump_stack.c
index c03154173cc7..f23b63f0a1c3 100644
--- a/lib/dump_stack.c
+++ b/lib/dump_stack.c
@@ -23,7 +23,7 @@ static void __dump_stack(void)
#ifdef CONFIG_SMP
static atomic_t dump_lock = ATOMIC_INIT(-1);
-void dump_stack(void)
+asmlinkage void dump_stack(void)
{
int was_locked;
int old;
@@ -55,7 +55,7 @@ retry:
preempt_enable();
}
#else
-void dump_stack(void)
+asmlinkage void dump_stack(void)
{
__dump_stack();
}
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/swiotlb.c b/lib/swiotlb.c
index d23762e6652c..4e8686c7e5a4 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -870,13 +870,13 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
swiotlb_full(hwdev, sg->length, dir, 0);
swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
attrs);
- sgl[0].dma_length = 0;
+ sg_dma_len(sgl) = 0;
return 0;
}
sg->dma_address = phys_to_dma(hwdev, map);
} else
sg->dma_address = dev_addr;
- sg->dma_length = sg->length;
+ sg_dma_len(sg) = sg->length;
}
return nelems;
}
@@ -904,7 +904,7 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
BUG_ON(dir == DMA_NONE);
for_each_sg(sgl, sg, nelems, i)
- unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
+ unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir);
}
EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
@@ -934,7 +934,7 @@ swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
for_each_sg(sgl, sg, nelems, i)
swiotlb_sync_single(hwdev, sg->dma_address,
- sg->dma_length, dir, target);
+ sg_dma_len(sg), dir, target);
}
void
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 739a36366b79..26559bdb4c49 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -26,6 +26,7 @@
#include <linux/math64.h>
#include <linux/uaccess.h>
#include <linux/ioport.h>
+#include <linux/dcache.h>
#include <net/addrconf.h>
#include <asm/page.h> /* for PAGE_SIZE */
@@ -532,6 +533,81 @@ char *string(char *buf, char *end, const char *s, struct printf_spec spec)
return buf;
}
+static void widen(char *buf, char *end, unsigned len, unsigned spaces)
+{
+ size_t size;
+ if (buf >= end) /* nowhere to put anything */
+ return;
+ size = end - buf;
+ if (size <= spaces) {
+ memset(buf, ' ', size);
+ return;
+ }
+ if (len) {
+ if (len > size - spaces)
+ len = size - spaces;
+ memmove(buf + spaces, buf, len);
+ }
+ memset(buf, ' ', spaces);
+}
+
+static noinline_for_stack
+char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
+ const char *fmt)
+{
+ const char *array[4], *s;
+ const struct dentry *p;
+ int depth;
+ int i, n;
+
+ switch (fmt[1]) {
+ case '2': case '3': case '4':
+ depth = fmt[1] - '0';
+ break;
+ default:
+ depth = 1;
+ }
+
+ rcu_read_lock();
+ for (i = 0; i < depth; i++, d = p) {
+ p = ACCESS_ONCE(d->d_parent);
+ array[i] = ACCESS_ONCE(d->d_name.name);
+ if (p == d) {
+ if (i)
+ array[i] = "";
+ i++;
+ break;
+ }
+ }
+ s = array[--i];
+ for (n = 0; n != spec.precision; n++, buf++) {
+ char c = *s++;
+ if (!c) {
+ if (!i)
+ break;
+ c = '/';
+ s = array[--i];
+ }
+ if (buf < end)
+ *buf = c;
+ }
+ rcu_read_unlock();
+ if (n < spec.field_width) {
+ /* we want to pad the sucker */
+ unsigned spaces = spec.field_width - n;
+ if (!(spec.flags & LEFT)) {
+ widen(buf - n, end, n, spaces);
+ return buf + spaces;
+ }
+ while (spaces--) {
+ if (buf < end)
+ *buf = ' ';
+ ++buf;
+ }
+ }
+ return buf;
+}
+
static noinline_for_stack
char *symbol_string(char *buf, char *end, void *ptr,
struct printf_spec spec, const char *fmt)
@@ -1253,6 +1329,12 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
spec.base = 16;
return number(buf, end,
(unsigned long long) *((phys_addr_t *)ptr), spec);
+ case 'd':
+ return dentry_name(buf, end, ptr, spec, fmt);
+ case 'D':
+ return dentry_name(buf, end,
+ ((const struct file *)ptr)->f_path.dentry,
+ spec, fmt);
}
spec.flags |= SMALL;
if (spec.field_width == -1) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-07 00:27:39 +0000