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-rw-r--r--drivers/base/core.c29
-rw-r--r--drivers/hid/hid-core.c20
-rw-r--r--drivers/s390/cio/ccwgroup.c18
-rw-r--r--drivers/scsi/scsi_sysfs.c14
-rw-r--r--fs/sysfs/file.c64
-rw-r--r--fs/sysfs/inode.c10
-rw-r--r--include/linux/device.h2
-rw-r--r--include/linux/sysfs.h9
8 files changed, 143 insertions, 23 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index f191afe62b4..ad0f4a2f25c 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -407,6 +407,35 @@ void device_remove_bin_file(struct device *dev, struct bin_attribute *attr)
}
EXPORT_SYMBOL_GPL(device_remove_bin_file);
+/**
+ * device_schedule_callback - helper to schedule a callback for a device
+ * @dev: device.
+ * @func: callback function to invoke later.
+ *
+ * Attribute methods must not unregister themselves or their parent device
+ * (which would amount to the same thing). Attempts to do so will deadlock,
+ * since unregistration is mutually exclusive with driver callbacks.
+ *
+ * Instead methods can call this routine, which will attempt to allocate
+ * and schedule a workqueue request to call back @func with @dev as its
+ * argument in the workqueue's process context. @dev will be pinned until
+ * @func returns.
+ *
+ * Returns 0 if the request was submitted, -ENOMEM if storage could not
+ * be allocated.
+ *
+ * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an
+ * underlying sysfs routine (since it is intended for use by attribute
+ * methods), and if sysfs isn't available you'll get nothing but -ENOSYS.
+ */
+int device_schedule_callback(struct device *dev,
+ void (*func)(struct device *))
+{
+ return sysfs_schedule_callback(&dev->kobj,
+ (void (*)(void *)) func, dev);
+}
+EXPORT_SYMBOL_GPL(device_schedule_callback);
+
static void klist_children_get(struct klist_node *n)
{
struct device *dev = container_of(n, struct device, knode_parent);
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 9c8157fb6d7..67f3347afcf 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -26,6 +26,7 @@
#include <asm/byteorder.h>
#include <linux/input.h>
#include <linux/wait.h>
+#include <linux/vmalloc.h>
#include <linux/hid.h>
#include <linux/hiddev.h>
@@ -654,12 +655,13 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
memcpy(device->rdesc, start, size);
device->rsize = size;
- if (!(parser = kzalloc(sizeof(struct hid_parser), GFP_KERNEL))) {
+ if (!(parser = vmalloc(sizeof(struct hid_parser)))) {
kfree(device->rdesc);
kfree(device->collection);
kfree(device);
return NULL;
}
+ memset(parser, 0, sizeof(struct hid_parser));
parser->device = device;
end = start + size;
@@ -668,7 +670,7 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
if (item.format != HID_ITEM_FORMAT_SHORT) {
dbg("unexpected long global item");
hid_free_device(device);
- kfree(parser);
+ vfree(parser);
return NULL;
}
@@ -676,7 +678,7 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
dbg("item %u %u %u %u parsing failed\n",
item.format, (unsigned)item.size, (unsigned)item.type, (unsigned)item.tag);
hid_free_device(device);
- kfree(parser);
+ vfree(parser);
return NULL;
}
@@ -684,23 +686,23 @@ struct hid_device *hid_parse_report(__u8 *start, unsigned size)
if (parser->collection_stack_ptr) {
dbg("unbalanced collection at end of report description");
hid_free_device(device);
- kfree(parser);
+ vfree(parser);
return NULL;
}
if (parser->local.delimiter_depth) {
dbg("unbalanced delimiter at end of report description");
hid_free_device(device);
- kfree(parser);
+ vfree(parser);
return NULL;
}
- kfree(parser);
+ vfree(parser);
return device;
}
}
dbg("item fetching failed at offset %d\n", (int)(end - start));
hid_free_device(device);
- kfree(parser);
+ vfree(parser);
return NULL;
}
EXPORT_SYMBOL_GPL(hid_parse_report);
@@ -872,10 +874,6 @@ static void hid_output_field(struct hid_field *field, __u8 *data)
unsigned size = field->report_size;
unsigned n;
- /* make sure the unused bits in the last byte are zeros */
- if (count > 0 && size > 0)
- data[(offset+count*size-1)/8] = 0;
-
for (n = 0; n < count; n++) {
if (field->logical_minimum < 0) /* signed values */
implement(data, offset + n * size, size, s32ton(field->value[n], size));
diff --git a/drivers/s390/cio/ccwgroup.c b/drivers/s390/cio/ccwgroup.c
index d48e3ca4752..5aeb68e732b 100644
--- a/drivers/s390/cio/ccwgroup.c
+++ b/drivers/s390/cio/ccwgroup.c
@@ -71,19 +71,31 @@ __ccwgroup_remove_symlinks(struct ccwgroup_device *gdev)
* Provide an 'ungroup' attribute so the user can remove group devices no
* longer needed or accidentially created. Saves memory :)
*/
+static void ccwgroup_ungroup_callback(struct device *dev)
+{
+ struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
+
+ __ccwgroup_remove_symlinks(gdev);
+ device_unregister(dev);
+}
+
static ssize_t
ccwgroup_ungroup_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
struct ccwgroup_device *gdev;
+ int rc;
gdev = to_ccwgroupdev(dev);
if (gdev->state != CCWGROUP_OFFLINE)
return -EINVAL;
- __ccwgroup_remove_symlinks(gdev);
- device_unregister(dev);
-
+ /* Note that we cannot unregister the device from one of its
+ * attribute methods, so we have to use this roundabout approach.
+ */
+ rc = device_schedule_callback(dev, ccwgroup_ungroup_callback);
+ if (rc)
+ count = rc;
return count;
}
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index c275dcac3f1..939de0de18b 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -452,10 +452,22 @@ store_rescan_field (struct device *dev, struct device_attribute *attr, const cha
}
static DEVICE_ATTR(rescan, S_IWUSR, NULL, store_rescan_field);
+static void sdev_store_delete_callback(struct device *dev)
+{
+ scsi_remove_device(to_scsi_device(dev));
+}
+
static ssize_t sdev_store_delete(struct device *dev, struct device_attribute *attr, const char *buf,
size_t count)
{
- scsi_remove_device(to_scsi_device(dev));
+ int rc;
+
+ /* An attribute cannot be unregistered by one of its own methods,
+ * so we have to use this roundabout approach.
+ */
+ rc = device_schedule_callback(dev, sdev_store_delete_callback);
+ if (rc)
+ count = rc;
return count;
};
static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 8d4d839a9d8..fc4633378dc 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -168,12 +168,12 @@ sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos)
ssize_t retval = 0;
down(&buffer->sem);
- if (buffer->orphaned) {
- retval = -ENODEV;
- goto out;
- }
if (buffer->needs_read_fill) {
- if ((retval = fill_read_buffer(file->f_path.dentry,buffer)))
+ if (buffer->orphaned)
+ retval = -ENODEV;
+ else
+ retval = fill_read_buffer(file->f_path.dentry,buffer);
+ if (retval)
goto out;
}
pr_debug("%s: count = %zd, ppos = %lld, buf = %s\n",
@@ -629,6 +629,60 @@ void sysfs_remove_file_from_group(struct kobject *kobj,
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_from_group);
+struct sysfs_schedule_callback_struct {
+ struct kobject *kobj;
+ void (*func)(void *);
+ void *data;
+ struct work_struct work;
+};
+
+static void sysfs_schedule_callback_work(struct work_struct *work)
+{
+ struct sysfs_schedule_callback_struct *ss = container_of(work,
+ struct sysfs_schedule_callback_struct, work);
+
+ (ss->func)(ss->data);
+ kobject_put(ss->kobj);
+ kfree(ss);
+}
+
+/**
+ * sysfs_schedule_callback - helper to schedule a callback for a kobject
+ * @kobj: object we're acting for.
+ * @func: callback function to invoke later.
+ * @data: argument to pass to @func.
+ *
+ * sysfs attribute methods must not unregister themselves or their parent
+ * kobject (which would amount to the same thing). Attempts to do so will
+ * deadlock, since unregistration is mutually exclusive with driver
+ * callbacks.
+ *
+ * Instead methods can call this routine, which will attempt to allocate
+ * and schedule a workqueue request to call back @func with @data as its
+ * argument in the workqueue's process context. @kobj will be pinned
+ * until @func returns.
+ *
+ * Returns 0 if the request was submitted, -ENOMEM if storage could not
+ * be allocated.
+ */
+int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
+ void *data)
+{
+ struct sysfs_schedule_callback_struct *ss;
+
+ ss = kmalloc(sizeof(*ss), GFP_KERNEL);
+ if (!ss)
+ return -ENOMEM;
+ kobject_get(kobj);
+ ss->kobj = kobj;
+ ss->func = func;
+ ss->data = data;
+ INIT_WORK(&ss->work, sysfs_schedule_callback_work);
+ schedule_work(&ss->work);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(sysfs_schedule_callback);
+
EXPORT_SYMBOL_GPL(sysfs_create_file);
EXPORT_SYMBOL_GPL(sysfs_remove_file);
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index ccb7d722c55..4de5c6b8991 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -222,13 +222,17 @@ const unsigned char * sysfs_get_name(struct sysfs_dirent *sd)
static inline void orphan_all_buffers(struct inode *node)
{
- struct sysfs_buffer_collection *set = node->i_private;
+ struct sysfs_buffer_collection *set;
struct sysfs_buffer *buf;
mutex_lock_nested(&node->i_mutex, I_MUTEX_CHILD);
- if (node->i_private) {
- list_for_each_entry(buf, &set->associates, associates)
+ set = node->i_private;
+ if (set) {
+ list_for_each_entry(buf, &set->associates, associates) {
+ down(&buf->sem);
buf->orphaned = 1;
+ up(&buf->sem);
+ }
}
mutex_unlock(&node->i_mutex);
}
diff --git a/include/linux/device.h b/include/linux/device.h
index 39a3199a826..caad9bba965 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -353,6 +353,8 @@ extern int __must_check device_create_bin_file(struct device *dev,
struct bin_attribute *attr);
extern void device_remove_bin_file(struct device *dev,
struct bin_attribute *attr);
+extern int device_schedule_callback(struct device *dev,
+ void (*func)(struct device *));
/* device resource management */
typedef void (*dr_release_t)(struct device *dev, void *res);
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 523405e1e1f..0544edda716 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -78,6 +78,9 @@ struct sysfs_ops {
#ifdef CONFIG_SYSFS
+extern int sysfs_schedule_callback(struct kobject *kobj,
+ void (*func)(void *), void *data);
+
extern int __must_check
sysfs_create_dir(struct kobject *, struct dentry *);
@@ -132,6 +135,12 @@ extern int __must_check sysfs_init(void);
#else /* CONFIG_SYSFS */
+static inline int sysfs_schedule_callback(struct kobject *kobj,
+ void (*func)(void *), void *data)
+{
+ return -ENOSYS;
+}
+
static inline int sysfs_create_dir(struct kobject * k, struct dentry *shadow)
{
return 0;
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-24 06:50:59 +0000