unsigned int count;
struct device dev;
struct ccw_device *cdev[0];
+ struct work_struct ungroup_work;
};
/**
}
static DEVICE_ATTR(pfgid, S_IRUGO, show_pfgid, NULL);
-static void recover_callback(struct device *dev)
+static ssize_t store_recover(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct zpci_dev *zdev = get_zdev(pdev);
int ret;
+ if (!device_remove_file_self(dev, attr))
+ return count;
+
pci_stop_and_remove_bus_device(pdev);
ret = zpci_disable_device(zdev);
if (ret)
- return;
+ return ret;
ret = zpci_enable_device(zdev);
if (ret)
- return;
+ return ret;
pci_rescan_bus(zdev->bus);
-}
-
-static ssize_t store_recover(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t count)
-{
- int rc = device_schedule_callback(dev, recover_callback);
- return rc ? rc : count;
+ return count;
}
static DEVICE_ATTR(recover, S_IWUSR, NULL, store_recover);
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
select HAVE_CC_STACKPROTECTOR
+ select GENERIC_CPU_AUTOPROBE
config INSTRUCTION_DECODER
def_bool y
config ARCH_HAS_CACHE_LINE_SIZE
def_bool y
-config ARCH_HAS_CPU_AUTOPROBE
- def_bool y
-
config HAVE_SETUP_PER_CPU_AREA
def_bool y
#define static_cpu_has_bug(bit) static_cpu_has((bit))
#define boot_cpu_has_bug(bit) cpu_has_bug(&boot_cpu_data, (bit))
+#define MAX_CPU_FEATURES (NCAPINTS * 32)
+#define cpu_have_feature boot_cpu_has
+
+#define CPU_FEATURE_TYPEFMT "x86,ven%04Xfam%04Xmod%04X"
+#define CPU_FEATURE_TYPEVAL boot_cpu_data.x86_vendor, boot_cpu_data.x86, \
+ boot_cpu_data.x86_model
+
#endif /* defined(__KERNEL__) && !defined(__ASSEMBLY__) */
#endif /* _ASM_X86_CPUFEATURE_H */
return NULL;
}
EXPORT_SYMBOL(x86_match_cpu);
-
-ssize_t arch_print_cpu_modalias(struct device *dev,
- struct device_attribute *attr,
- char *bufptr)
-{
- int size = PAGE_SIZE;
- int i, n;
- char *buf = bufptr;
-
- n = snprintf(buf, size, "x86cpu:vendor:%04X:family:%04X:"
- "model:%04X:feature:",
- boot_cpu_data.x86_vendor,
- boot_cpu_data.x86,
- boot_cpu_data.x86_model);
- size -= n;
- buf += n;
- size -= 1;
- for (i = 0; i < NCAPINTS*32; i++) {
- if (boot_cpu_has(i)) {
- n = snprintf(buf, size, ",%04X", i);
- if (n >= size) {
- WARN(1, "x86 features overflow page\n");
- break;
- }
- size -= n;
- buf += n;
- }
- }
- *buf++ = '\n';
- return buf - bufptr;
-}
-
-int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
-{
- char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
- if (buf) {
- arch_print_cpu_modalias(NULL, NULL, buf);
- add_uevent_var(env, "MODALIAS=%s", buf);
- kfree(buf);
- }
- return 0;
-}
bool
default n
+config GENERIC_CPU_AUTOPROBE
+ bool
+
config SOC_BUS
bool
*/
#include <linux/attribute_container.h>
-#include <linux/init.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/genhd.h>
#include <linux/kallsyms.h>
#include <linux/mutex.h>
-#include <linux/async.h>
#include <linux/pm_runtime.h>
#include <linux/netdevice.h>
#include <linux/sysfs.h>
}
EXPORT_SYMBOL_GPL(device_remove_file);
+/**
+ * device_remove_file_self - remove sysfs attribute file from its own method.
+ * @dev: device.
+ * @attr: device attribute descriptor.
+ *
+ * See kernfs_remove_self() for details.
+ */
+bool device_remove_file_self(struct device *dev,
+ const struct device_attribute *attr)
+{
+ if (dev)
+ return sysfs_remove_file_self(&dev->kobj, &attr->attr);
+ else
+ return false;
+}
+EXPORT_SYMBOL_GPL(device_remove_file_self);
+
/**
* device_create_bin_file - create sysfs binary attribute file for device.
* @dev: device.
spin_lock(&devices_kset->list_lock);
}
spin_unlock(&devices_kset->list_lock);
- async_synchronize_full();
}
/*
return pos;
}
-EXPORT_SYMBOL(create_syslog_header);
int dev_vprintk_emit(int level, const struct device *dev,
const char *fmt, va_list args)
#include <linux/percpu.h>
#include <linux/acpi.h>
#include <linux/of.h>
+#include <linux/cpufeature.h>
#include "base.h"
*/
}
+#ifdef CONFIG_GENERIC_CPU_AUTOPROBE
+static ssize_t print_cpu_modalias(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ ssize_t n;
+ u32 i;
+
+ n = sprintf(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
+ CPU_FEATURE_TYPEVAL);
+
+ for (i = 0; i < MAX_CPU_FEATURES; i++)
+ if (cpu_have_feature(i)) {
+ if (PAGE_SIZE < n + sizeof(",XXXX\n")) {
+ WARN(1, "CPU features overflow page\n");
+ break;
+ }
+ n += sprintf(&buf[n], ",%04X", i);
+ }
+ buf[n++] = '\n';
+ return n;
+}
+
+static int cpu_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+ if (buf) {
+ print_cpu_modalias(NULL, NULL, buf);
+ add_uevent_var(env, "MODALIAS=%s", buf);
+ kfree(buf);
+ }
+ return 0;
+}
+#endif
+
/*
* register_cpu - Setup a sysfs device for a CPU.
* @cpu - cpu->hotpluggable field set to 1 will generate a control file in
cpu->dev.offline_disabled = !cpu->hotpluggable;
cpu->dev.offline = !cpu_online(num);
cpu->dev.of_node = of_get_cpu_node(num, NULL);
-#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
- cpu->dev.bus->uevent = arch_cpu_uevent;
+#ifdef CONFIG_GENERIC_CPU_AUTOPROBE
+ cpu->dev.bus->uevent = cpu_uevent;
#endif
cpu->dev.groups = common_cpu_attr_groups;
if (cpu->hotpluggable)
}
EXPORT_SYMBOL_GPL(get_cpu_device);
-#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
-static DEVICE_ATTR(modalias, 0444, arch_print_cpu_modalias, NULL);
+#ifdef CONFIG_GENERIC_CPU_AUTOPROBE
+static DEVICE_ATTR(modalias, 0444, print_cpu_modalias, NULL);
#endif
static struct attribute *cpu_root_attrs[] = {
&cpu_attrs[2].attr.attr,
&dev_attr_kernel_max.attr,
&dev_attr_offline.attr,
-#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
+#ifdef CONFIG_GENERIC_CPU_AUTOPROBE
&dev_attr_modalias.attr,
#endif
NULL
* @dmabuf: [in] buffer to attach device to.
* @dev: [in] device to be attached.
*
- * Returns struct dma_buf_attachment * for this attachment; may return negative
- * error codes.
- *
+ * Returns struct dma_buf_attachment * for this attachment; returns ERR_PTR on
+ * error.
*/
struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
struct device *dev)
* @attach: [in] attachment whose scatterlist is to be returned
* @direction: [in] direction of DMA transfer
*
- * Returns sg_table containing the scatterlist to be returned; may return NULL
- * or ERR_PTR.
- *
+ * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
+ * on error.
*/
struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *attach,
enum dma_data_direction direction)
return ERR_PTR(-EINVAL);
sg_table = attach->dmabuf->ops->map_dma_buf(attach, direction);
+ if (!sg_table)
+ sg_table = ERR_PTR(-ENOMEM);
return sg_table;
}
* These calls are optional in drivers. The intended use for them
* is for mapping objects linear in kernel space for high use objects.
* Please attempt to use kmap/kunmap before thinking about these interfaces.
+ *
+ * Returns NULL on error.
*/
void *dma_buf_vmap(struct dma_buf *dmabuf)
{
BUG_ON(dmabuf->vmap_ptr);
ptr = dmabuf->ops->vmap(dmabuf);
- if (IS_ERR_OR_NULL(ptr))
+ if (WARN_ON_ONCE(IS_ERR(ptr)))
+ ptr = NULL;
+ if (!ptr)
goto out_unlock;
dmabuf->vmap_ptr = ptr;
* see the mapped 'buf->data' once the loading
* is completed.
* */
- fw_map_pages_buf(fw_buf);
+ if (fw_map_pages_buf(fw_buf))
+ dev_err(dev, "%s: map pages failed\n",
+ __func__);
list_del_init(&fw_buf->pending_list);
complete_all(&fw_buf->completion);
break;
dev_set_uevent_suppress(f_dev, false);
dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
if (timeout != MAX_SCHEDULE_TIMEOUT)
- schedule_delayed_work(&fw_priv->timeout_work, timeout);
+ queue_delayed_work(system_power_efficient_wq,
+ &fw_priv->timeout_work, timeout);
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
wait_for_completion(&buf->completion);
cancel_delayed_work_sync(&fw_priv->timeout_work);
+ if (!buf->data)
+ retval = -ENOMEM;
device_remove_file(f_dev, &dev_attr_loading);
err_del_bin_attr:
*/
static void device_uncache_fw_images_delay(unsigned long delay)
{
- schedule_delayed_work(&fw_cache.work,
- msecs_to_jiffies(delay));
+ queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
+ msecs_to_jiffies(delay));
}
static int fw_pm_notify(struct notifier_block *notify_block,
void unregister_one_node(int nid)
{
+ if (!node_devices[nid])
+ return;
+
unregister_node(node_devices[nid]);
+ kfree(node_devices[nid]);
node_devices[nid] = NULL;
}
struct platform_device *dev = to_platform_device(_dev);
int ret;
- if (ACPI_HANDLE(_dev))
- acpi_dev_pm_attach(_dev, true);
+ acpi_dev_pm_attach(_dev, true);
ret = drv->probe(dev);
- if (ret && ACPI_HANDLE(_dev))
+ if (ret)
acpi_dev_pm_detach(_dev, true);
if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) {
int ret;
ret = drv->remove(dev);
- if (ACPI_HANDLE(_dev))
- acpi_dev_pm_detach(_dev, true);
+ acpi_dev_pm_detach(_dev, true);
return ret;
}
struct platform_device *dev = to_platform_device(_dev);
drv->shutdown(dev);
- if (ACPI_HANDLE(_dev))
- acpi_dev_pm_detach(_dev, true);
+ acpi_dev_pm_detach(_dev, true);
}
/**
* This file is released under the GPLv2.
*/
-#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/io.h>
* This file is released under the GPLv2.
*/
-#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/export.h>
* This file is released under the GPLv2.
*/
-#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
* This file is released under the GPLv2.
*/
-#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/pm_domain.h>
#include <linux/pm_qos.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/err.h>
-#include <linux/init.h>
#include <linux/slab.h>
#include <linux/cpufreq.h>
#include <linux/device.h>
#include <linux/regmap.h>
#include <linux/i2c.h>
#include <linux/module.h>
-#include <linux/init.h>
static int regmap_i2c_write(void *context, const void *data, size_t count)
{
#include <linux/clk.h>
#include <linux/err.h>
-#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>
-#include <linux/init.h>
#include <linux/module.h>
#include "internal.h"
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
-#include <linux/init.h>
#include <linux/mm.h>
#include <linux/cpu.h>
#include <linux/module.h>
goto out_remove_sysfs_files;
}
- ret = efivars_sysfs_init();
- if (ret) {
- printk(KERN_INFO "gsmi: Failed to create efivars files\n");
- efivars_unregister(&efivars);
- goto out_remove_sysfs_files;
- }
-
register_reboot_notifier(&gsmi_reboot_notifier);
register_die_notifier(&gsmi_die_notifier);
atomic_notifier_chain_register(&panic_notifier_list,
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/dmi.h>
+#include <linux/io.h>
#include <asm/bios_ebda.h>
#define BIOS_MEMCONSOLE_V1_MAGIC 0xDEADBABE
};
} __packed;
-static char *memconsole_baseaddr;
+static u32 memconsole_baseaddr;
static size_t memconsole_length;
static ssize_t memconsole_read(struct file *filp, struct kobject *kobp,
struct bin_attribute *bin_attr, char *buf,
loff_t pos, size_t count)
{
- return memory_read_from_buffer(buf, count, &pos, memconsole_baseaddr,
- memconsole_length);
+ char *memconsole;
+ ssize_t ret;
+
+ memconsole = ioremap_cache(memconsole_baseaddr, memconsole_length);
+ if (!memconsole) {
+ pr_err("memconsole: ioremap_cache failed\n");
+ return -ENOMEM;
+ }
+ ret = memory_read_from_buffer(buf, count, &pos, memconsole,
+ memconsole_length);
+ iounmap(memconsole);
+ return ret;
}
static struct bin_attribute memconsole_bin_attr = {
};
-static void found_v1_header(struct biosmemcon_ebda *hdr)
+static void __init found_v1_header(struct biosmemcon_ebda *hdr)
{
- printk(KERN_INFO "BIOS console v1 EBDA structure found at %p\n", hdr);
- printk(KERN_INFO "BIOS console buffer at 0x%.8x, "
+ pr_info("BIOS console v1 EBDA structure found at %p\n", hdr);
+ pr_info("BIOS console buffer at 0x%.8x, "
"start = %d, end = %d, num = %d\n",
hdr->v1.buffer_addr, hdr->v1.start,
hdr->v1.end, hdr->v1.num_chars);
memconsole_length = hdr->v1.num_chars;
- memconsole_baseaddr = phys_to_virt(hdr->v1.buffer_addr);
+ memconsole_baseaddr = hdr->v1.buffer_addr;
}
-static void found_v2_header(struct biosmemcon_ebda *hdr)
+static void __init found_v2_header(struct biosmemcon_ebda *hdr)
{
- printk(KERN_INFO "BIOS console v2 EBDA structure found at %p\n", hdr);
- printk(KERN_INFO "BIOS console buffer at 0x%.8x, "
+ pr_info("BIOS console v2 EBDA structure found at %p\n", hdr);
+ pr_info("BIOS console buffer at 0x%.8x, "
"start = %d, end = %d, num_bytes = %d\n",
hdr->v2.buffer_addr, hdr->v2.start,
hdr->v2.end, hdr->v2.num_bytes);
memconsole_length = hdr->v2.end - hdr->v2.start;
- memconsole_baseaddr = phys_to_virt(hdr->v2.buffer_addr
- + hdr->v2.start);
+ memconsole_baseaddr = hdr->v2.buffer_addr + hdr->v2.start;
}
/*
* Search through the EBDA for the BIOS Memory Console, and
* set the global variables to point to it. Return true if found.
*/
-static bool found_memconsole(void)
+static bool __init found_memconsole(void)
{
unsigned int address;
size_t length, cur;
address = get_bios_ebda();
if (!address) {
- printk(KERN_INFO "BIOS EBDA non-existent.\n");
+ pr_info("BIOS EBDA non-existent.\n");
return false;
}
}
}
- printk(KERN_INFO "BIOS console EBDA structure not found!\n");
+ pr_info("BIOS console EBDA structure not found!\n");
return false;
}
static int __init memconsole_init(void)
{
- int ret;
-
if (!dmi_check_system(memconsole_dmi_table))
return -ENODEV;
return -ENODEV;
memconsole_bin_attr.size = memconsole_length;
-
- ret = sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
-
- return ret;
+ return sysfs_create_bin_file(firmware_kobj, &memconsole_bin_attr);
}
static void __exit memconsole_exit(void)
get_dma_buf(dma_buf);
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
- if (IS_ERR_OR_NULL(sgt)) {
+ if (IS_ERR(sgt)) {
ret = PTR_ERR(sgt);
goto fail_detach;
}
get_dma_buf(dma_buf);
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
- if (IS_ERR_OR_NULL(sgt)) {
+ if (IS_ERR(sgt)) {
ret = PTR_ERR(sgt);
goto err_buf_detach;
}
/* get the associated scatterlist for this buffer */
sgt = dma_buf_map_attachment(buf->db_attach, buf->dma_dir);
- if (IS_ERR_OR_NULL(sgt)) {
+ if (IS_ERR(sgt)) {
pr_err("Error getting dmabuf scatterlist\n");
return -EINVAL;
}
(S_IWUSR|S_IWGRP),
NULL, dev_rescan_store);
-static void remove_callback(struct device *dev)
-{
- pci_stop_and_remove_bus_device_locked(to_pci_dev(dev));
-}
-
static ssize_t
-remove_store(struct device *dev, struct device_attribute *dummy,
+remove_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
- int ret = 0;
unsigned long val;
if (kstrtoul(buf, 0, &val) < 0)
return -EINVAL;
- /* An attribute cannot be unregistered by one of its own methods,
- * so we have to use this roundabout approach.
- */
- if (val)
- ret = device_schedule_callback(dev, remove_callback);
- if (ret)
- count = ret;
+ if (val && device_remove_file_self(dev, attr))
+ pci_stop_and_remove_bus_device_locked(to_pci_dev(dev));
return count;
}
static struct device_attribute dev_remove_attr = __ATTR(remove,
return rc;
}
-static void dcssblk_unregister_callback(struct device *dev)
-{
- device_unregister(dev);
- put_device(dev);
-}
-
/*
* device attribute for switching shared/nonshared (exclusive)
* operation (show + store)
blk_cleanup_queue(dev_info->dcssblk_queue);
dev_info->gd->queue = NULL;
put_disk(dev_info->gd);
- rc = device_schedule_callback(dev, dcssblk_unregister_callback);
+ up_write(&dcssblk_devices_sem);
+
+ if (device_remove_file_self(dev, attr)) {
+ device_unregister(dev);
+ put_device(dev);
+ }
+ return rc;
out:
up_write(&dcssblk_devices_sem);
return rc;
* 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)
+static void ccwgroup_ungroup(struct ccwgroup_device *gdev)
{
- struct ccwgroup_device *gdev = to_ccwgroupdev(dev);
-
mutex_lock(&gdev->reg_mutex);
if (device_is_registered(&gdev->dev)) {
__ccwgroup_remove_symlinks(gdev);
- device_unregister(dev);
+ device_unregister(&gdev->dev);
__ccwgroup_remove_cdev_refs(gdev);
}
mutex_unlock(&gdev->reg_mutex);
rc = -EINVAL;
goto out;
}
- /* 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 (device_remove_file_self(dev, attr))
+ ccwgroup_ungroup(gdev);
out:
if (rc) {
if (rc != -EAGAIN)
NULL,
};
+static void ccwgroup_ungroup_workfn(struct work_struct *work)
+{
+ struct ccwgroup_device *gdev =
+ container_of(work, struct ccwgroup_device, ungroup_work);
+
+ ccwgroup_ungroup(gdev);
+}
+
static void ccwgroup_release(struct device *dev)
{
kfree(to_ccwgroupdev(dev));
atomic_set(&gdev->onoff, 0);
mutex_init(&gdev->reg_mutex);
mutex_lock(&gdev->reg_mutex);
+ INIT_WORK(&gdev->ungroup_work, ccwgroup_ungroup_workfn);
gdev->count = num_devices;
gdev->dev.bus = &ccwgroup_bus_type;
gdev->dev.parent = parent;
static int ccwgroup_notifier(struct notifier_block *nb, unsigned long action,
void *data)
{
- struct device *dev = data;
+ struct ccwgroup_device *gdev = to_ccwgroupdev(data);
if (action == BUS_NOTIFY_UNBIND_DRIVER)
- device_schedule_callback(dev, ccwgroup_ungroup_callback);
+ schedule_work(&gdev->ungroup_work);
return NOTIFY_OK;
}
}
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)
{
- 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;
+ if (device_remove_file_self(dev, attr))
+ scsi_remove_device(to_scsi_device(dev));
return count;
};
static DEVICE_ATTR(delete, S_IWUSR, NULL, sdev_store_delete);
menu "Pseudo filesystems"
source "fs/proc/Kconfig"
+source "fs/kernfs/Kconfig"
source "fs/sysfs/Kconfig"
config TMPFS
obj-y += quota/
obj-$(CONFIG_PROC_FS) += proc/
-obj-$(CONFIG_SYSFS) += sysfs/ kernfs/
+obj-$(CONFIG_KERNFS) += kernfs/
+obj-$(CONFIG_SYSFS) += sysfs/
obj-$(CONFIG_CONFIGFS_FS) += configfs/
obj-y += devpts/
--- /dev/null
+#
+# KERNFS should be selected by its users
+#
+
+config KERNFS
+ bool
+ default n
* This file is released under the GPLv2.
*/
+#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/idr.h>
#include "kernfs-internal.h"
DEFINE_MUTEX(kernfs_mutex);
+static DEFINE_SPINLOCK(kernfs_rename_lock); /* kn->parent and ->name */
+static char kernfs_pr_cont_buf[PATH_MAX]; /* protected by rename_lock */
#define rb_to_kn(X) rb_entry((X), struct kernfs_node, rb)
+static bool kernfs_active(struct kernfs_node *kn)
+{
+ lockdep_assert_held(&kernfs_mutex);
+ return atomic_read(&kn->active) >= 0;
+}
+
+static bool kernfs_lockdep(struct kernfs_node *kn)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ return kn->flags & KERNFS_LOCKDEP;
+#else
+ return false;
+#endif
+}
+
+static int kernfs_name_locked(struct kernfs_node *kn, char *buf, size_t buflen)
+{
+ return strlcpy(buf, kn->parent ? kn->name : "/", buflen);
+}
+
+static char * __must_check kernfs_path_locked(struct kernfs_node *kn, char *buf,
+ size_t buflen)
+{
+ char *p = buf + buflen;
+ int len;
+
+ *--p = '\0';
+
+ do {
+ len = strlen(kn->name);
+ if (p - buf < len + 1) {
+ buf[0] = '\0';
+ p = NULL;
+ break;
+ }
+ p -= len;
+ memcpy(p, kn->name, len);
+ *--p = '/';
+ kn = kn->parent;
+ } while (kn && kn->parent);
+
+ return p;
+}
+
+/**
+ * kernfs_name - obtain the name of a given node
+ * @kn: kernfs_node of interest
+ * @buf: buffer to copy @kn's name into
+ * @buflen: size of @buf
+ *
+ * Copies the name of @kn into @buf of @buflen bytes. The behavior is
+ * similar to strlcpy(). It returns the length of @kn's name and if @buf
+ * isn't long enough, it's filled upto @buflen-1 and nul terminated.
+ *
+ * This function can be called from any context.
+ */
+int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&kernfs_rename_lock, flags);
+ ret = kernfs_name_locked(kn, buf, buflen);
+ spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+ return ret;
+}
+
+/**
+ * kernfs_path - build full path of a given node
+ * @kn: kernfs_node of interest
+ * @buf: buffer to copy @kn's name into
+ * @buflen: size of @buf
+ *
+ * Builds and returns the full path of @kn in @buf of @buflen bytes. The
+ * path is built from the end of @buf so the returned pointer usually
+ * doesn't match @buf. If @buf isn't long enough, @buf is nul terminated
+ * and %NULL is returned.
+ */
+char *kernfs_path(struct kernfs_node *kn, char *buf, size_t buflen)
+{
+ unsigned long flags;
+ char *p;
+
+ spin_lock_irqsave(&kernfs_rename_lock, flags);
+ p = kernfs_path_locked(kn, buf, buflen);
+ spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+ return p;
+}
+
+/**
+ * pr_cont_kernfs_name - pr_cont name of a kernfs_node
+ * @kn: kernfs_node of interest
+ *
+ * This function can be called from any context.
+ */
+void pr_cont_kernfs_name(struct kernfs_node *kn)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&kernfs_rename_lock, flags);
+
+ kernfs_name_locked(kn, kernfs_pr_cont_buf, sizeof(kernfs_pr_cont_buf));
+ pr_cont("%s", kernfs_pr_cont_buf);
+
+ spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+}
+
+/**
+ * pr_cont_kernfs_path - pr_cont path of a kernfs_node
+ * @kn: kernfs_node of interest
+ *
+ * This function can be called from any context.
+ */
+void pr_cont_kernfs_path(struct kernfs_node *kn)
+{
+ unsigned long flags;
+ char *p;
+
+ spin_lock_irqsave(&kernfs_rename_lock, flags);
+
+ p = kernfs_path_locked(kn, kernfs_pr_cont_buf,
+ sizeof(kernfs_pr_cont_buf));
+ if (p)
+ pr_cont("%s", p);
+ else
+ pr_cont("<name too long>");
+
+ spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+}
+
+/**
+ * kernfs_get_parent - determine the parent node and pin it
+ * @kn: kernfs_node of interest
+ *
+ * Determines @kn's parent, pins and returns it. This function can be
+ * called from any context.
+ */
+struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn)
+{
+ struct kernfs_node *parent;
+ unsigned long flags;
+
+ spin_lock_irqsave(&kernfs_rename_lock, flags);
+ parent = kn->parent;
+ kernfs_get(parent);
+ spin_unlock_irqrestore(&kernfs_rename_lock, flags);
+
+ return parent;
+}
+
/**
* kernfs_name_hash
* @name: Null terminated string to hash
hash = (end_name_hash(hash) ^ hash_ptr((void *)ns, 31));
hash &= 0x7fffffffU;
/* Reserve hash numbers 0, 1 and INT_MAX for magic directory entries */
- if (hash < 1)
+ if (hash < 2)
hash += 2;
if (hash >= INT_MAX)
hash = INT_MAX - 1;
* kernfs_unlink_sibling - unlink kernfs_node from sibling rbtree
* @kn: kernfs_node of interest
*
- * Unlink @kn from its sibling rbtree which starts from
- * kn->parent->dir.children.
+ * Try to unlink @kn from its sibling rbtree which starts from
+ * kn->parent->dir.children. Returns %true if @kn was actually
+ * removed, %false if @kn wasn't on the rbtree.
*
* Locking:
* mutex_lock(kernfs_mutex)
*/
-static void kernfs_unlink_sibling(struct kernfs_node *kn)
+static bool kernfs_unlink_sibling(struct kernfs_node *kn)
{
+ if (RB_EMPTY_NODE(&kn->rb))
+ return false;
+
if (kernfs_type(kn) == KERNFS_DIR)
kn->parent->dir.subdirs--;
rb_erase(&kn->rb, &kn->parent->dir.children);
+ RB_CLEAR_NODE(&kn->rb);
+ return true;
}
/**
if (!atomic_inc_unless_negative(&kn->active))
return NULL;
- if (kn->flags & KERNFS_LOCKDEP)
+ if (kernfs_lockdep(kn))
rwsem_acquire_read(&kn->dep_map, 0, 1, _RET_IP_);
return kn;
}
*/
void kernfs_put_active(struct kernfs_node *kn)
{
+ struct kernfs_root *root = kernfs_root(kn);
int v;
if (unlikely(!kn))
return;
- if (kn->flags & KERNFS_LOCKDEP)
+ if (kernfs_lockdep(kn))
rwsem_release(&kn->dep_map, 1, _RET_IP_);
v = atomic_dec_return(&kn->active);
if (likely(v != KN_DEACTIVATED_BIAS))
return;
- /*
- * atomic_dec_return() is a mb(), we'll always see the updated
- * kn->u.completion.
- */
- complete(kn->u.completion);
+ wake_up_all(&root->deactivate_waitq);
}
/**
- * kernfs_deactivate - deactivate kernfs_node
- * @kn: kernfs_node to deactivate
+ * kernfs_drain - drain kernfs_node
+ * @kn: kernfs_node to drain
*
- * Deny new active references and drain existing ones.
+ * Drain existing usages and nuke all existing mmaps of @kn. Mutiple
+ * removers may invoke this function concurrently on @kn and all will
+ * return after draining is complete.
*/
-static void kernfs_deactivate(struct kernfs_node *kn)
+static void kernfs_drain(struct kernfs_node *kn)
+ __releases(&kernfs_mutex) __acquires(&kernfs_mutex)
{
- DECLARE_COMPLETION_ONSTACK(wait);
- int v;
+ struct kernfs_root *root = kernfs_root(kn);
- BUG_ON(!(kn->flags & KERNFS_REMOVED));
-
- if (!(kernfs_type(kn) & KERNFS_ACTIVE_REF))
- return;
+ lockdep_assert_held(&kernfs_mutex);
+ WARN_ON_ONCE(kernfs_active(kn));
- kn->u.completion = (void *)&wait;
+ mutex_unlock(&kernfs_mutex);
- if (kn->flags & KERNFS_LOCKDEP)
+ if (kernfs_lockdep(kn)) {
rwsem_acquire(&kn->dep_map, 0, 0, _RET_IP_);
- /* atomic_add_return() is a mb(), put_active() will always see
- * the updated kn->u.completion.
- */
- v = atomic_add_return(KN_DEACTIVATED_BIAS, &kn->active);
-
- if (v != KN_DEACTIVATED_BIAS) {
- if (kn->flags & KERNFS_LOCKDEP)
+ if (atomic_read(&kn->active) != KN_DEACTIVATED_BIAS)
lock_contended(&kn->dep_map, _RET_IP_);
- wait_for_completion(&wait);
}
- if (kn->flags & KERNFS_LOCKDEP) {
+ /* but everyone should wait for draining */
+ wait_event(root->deactivate_waitq,
+ atomic_read(&kn->active) == KN_DEACTIVATED_BIAS);
+
+ if (kernfs_lockdep(kn)) {
lock_acquired(&kn->dep_map, _RET_IP_);
rwsem_release(&kn->dep_map, 1, _RET_IP_);
}
+
+ kernfs_unmap_bin_file(kn);
+
+ mutex_lock(&kernfs_mutex);
}
/**
return;
root = kernfs_root(kn);
repeat:
- /* Moving/renaming is always done while holding reference.
+ /*
+ * Moving/renaming is always done while holding reference.
* kn->parent won't change beneath us.
*/
parent = kn->parent;
- WARN(!(kn->flags & KERNFS_REMOVED), "kernfs: free using entry: %s/%s\n",
- parent ? parent->name : "", kn->name);
+ WARN_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS,
+ "kernfs_put: %s/%s: released with incorrect active_ref %d\n",
+ parent ? parent->name : "", kn->name, atomic_read(&kn->active));
if (kernfs_type(kn) == KERNFS_LINK)
kernfs_put(kn->symlink.target_kn);
kn = dentry->d_fsdata;
mutex_lock(&kernfs_mutex);
- /* The kernfs node has been deleted */
- if (kn->flags & KERNFS_REMOVED)
+ /* The kernfs node has been deactivated */
+ if (!kernfs_active(kn))
goto out_bad;
/* The kernfs node has been moved? */
.d_release = kernfs_dop_release,
};
+/**
+ * kernfs_node_from_dentry - determine kernfs_node associated with a dentry
+ * @dentry: the dentry in question
+ *
+ * Return the kernfs_node associated with @dentry. If @dentry is not a
+ * kernfs one, %NULL is returned.
+ *
+ * While the returned kernfs_node will stay accessible as long as @dentry
+ * is accessible, the returned node can be in any state and the caller is
+ * fully responsible for determining what's accessible.
+ */
+struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry)
+{
+ if (dentry->d_sb->s_op == &kernfs_sops)
+ return dentry->d_fsdata;
+ return NULL;
+}
+
static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
const char *name, umode_t mode,
unsigned flags)
kn->ino = ret;
atomic_set(&kn->count, 1);
- atomic_set(&kn->active, 0);
+ atomic_set(&kn->active, KN_DEACTIVATED_BIAS);
+ RB_CLEAR_NODE(&kn->rb);
kn->name = name;
kn->mode = mode;
- kn->flags = flags | KERNFS_REMOVED;
+ kn->flags = flags;
return kn;
return kn;
}
-/**
- * kernfs_addrm_start - prepare for kernfs_node add/remove
- * @acxt: pointer to kernfs_addrm_cxt to be used
- *
- * This function is called when the caller is about to add or remove
- * kernfs_node. This function acquires kernfs_mutex. @acxt is used
- * to keep and pass context to other addrm functions.
- *
- * LOCKING:
- * Kernel thread context (may sleep). kernfs_mutex is locked on
- * return.
- */
-void kernfs_addrm_start(struct kernfs_addrm_cxt *acxt)
- __acquires(kernfs_mutex)
-{
- memset(acxt, 0, sizeof(*acxt));
-
- mutex_lock(&kernfs_mutex);
-}
-
/**
* kernfs_add_one - add kernfs_node to parent without warning
- * @acxt: addrm context to use
* @kn: kernfs_node to be added
*
* The caller must already have initialized @kn->parent. This
* function increments nlink of the parent's inode if @kn is a
* directory and link into the children list of the parent.
*
- * This function should be called between calls to
- * kernfs_addrm_start() and kernfs_addrm_finish() and should be passed
- * the same @acxt as passed to kernfs_addrm_start().
- *
- * LOCKING:
- * Determined by kernfs_addrm_start().
- *
* RETURNS:
* 0 on success, -EEXIST if entry with the given name already
* exists.
*/
-int kernfs_add_one(struct kernfs_addrm_cxt *acxt, struct kernfs_node *kn)
+int kernfs_add_one(struct kernfs_node *kn)
{
struct kernfs_node *parent = kn->parent;
- bool has_ns = kernfs_ns_enabled(parent);
struct kernfs_iattrs *ps_iattr;
+ bool has_ns;
int ret;
- if (has_ns != (bool)kn->ns) {
- WARN(1, KERN_WARNING "kernfs: ns %s in '%s' for '%s'\n",
- has_ns ? "required" : "invalid", parent->name, kn->name);
- return -EINVAL;
- }
+ mutex_lock(&kernfs_mutex);
+
+ ret = -EINVAL;
+ has_ns = kernfs_ns_enabled(parent);
+ if (WARN(has_ns != (bool)kn->ns, KERN_WARNING "kernfs: ns %s in '%s' for '%s'\n",
+ has_ns ? "required" : "invalid", parent->name, kn->name))
+ goto out_unlock;
if (kernfs_type(parent) != KERNFS_DIR)
- return -EINVAL;
+ goto out_unlock;
- if (parent->flags & KERNFS_REMOVED)
- return -ENOENT;
+ ret = -ENOENT;
+ if ((parent->flags & KERNFS_ACTIVATED) && !kernfs_active(parent))
+ goto out_unlock;
kn->hash = kernfs_name_hash(kn->name, kn->ns);
ret = kernfs_link_sibling(kn);
if (ret)
- return ret;
+ goto out_unlock;
/* Update timestamps on the parent */
ps_iattr = parent->iattr;
ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME;
}
- /* Mark the entry added into directory tree */
- kn->flags &= ~KERNFS_REMOVED;
-
- return 0;
-}
-
-/**
- * kernfs_remove_one - remove kernfs_node from parent
- * @acxt: addrm context to use
- * @kn: kernfs_node to be removed
- *
- * Mark @kn removed and drop nlink of parent inode if @kn is a
- * directory. @kn is unlinked from the children list.
- *
- * This function should be called between calls to
- * kernfs_addrm_start() and kernfs_addrm_finish() and should be
- * passed the same @acxt as passed to kernfs_addrm_start().
- *
- * LOCKING:
- * Determined by kernfs_addrm_start().
- */
-static void kernfs_remove_one(struct kernfs_addrm_cxt *acxt,
- struct kernfs_node *kn)
-{
- struct kernfs_iattrs *ps_iattr;
+ mutex_unlock(&kernfs_mutex);
/*
- * Removal can be called multiple times on the same node. Only the
- * first invocation is effective and puts the base ref.
+ * Activate the new node unless CREATE_DEACTIVATED is requested.
+ * If not activated here, the kernfs user is responsible for
+ * activating the node with kernfs_activate(). A node which hasn't
+ * been activated is not visible to userland and its removal won't
+ * trigger deactivation.
*/
- if (kn->flags & KERNFS_REMOVED)
- return;
-
- if (kn->parent) {
- kernfs_unlink_sibling(kn);
-
- /* Update timestamps on the parent */
- ps_iattr = kn->parent->iattr;
- if (ps_iattr) {
- ps_iattr->ia_iattr.ia_ctime = CURRENT_TIME;
- ps_iattr->ia_iattr.ia_mtime = CURRENT_TIME;
- }
- }
-
- kn->flags |= KERNFS_REMOVED;
- kn->u.removed_list = acxt->removed;
- acxt->removed = kn;
-}
+ if (!(kernfs_root(kn)->flags & KERNFS_ROOT_CREATE_DEACTIVATED))
+ kernfs_activate(kn);
+ return 0;
-/**
- * kernfs_addrm_finish - finish up kernfs_node add/remove
- * @acxt: addrm context to finish up
- *
- * Finish up kernfs_node add/remove. Resources acquired by
- * kernfs_addrm_start() are released and removed kernfs_nodes are
- * cleaned up.
- *
- * LOCKING:
- * kernfs_mutex is released.
- */
-void kernfs_addrm_finish(struct kernfs_addrm_cxt *acxt)
- __releases(kernfs_mutex)
-{
- /* release resources acquired by kernfs_addrm_start() */
+out_unlock:
mutex_unlock(&kernfs_mutex);
-
- /* kill removed kernfs_nodes */
- while (acxt->removed) {
- struct kernfs_node *kn = acxt->removed;
-
- acxt->removed = kn->u.removed_list;
-
- kernfs_deactivate(kn);
- kernfs_unmap_bin_file(kn);
- kernfs_put(kn);
- }
+ return ret;
}
/**
/**
* kernfs_create_root - create a new kernfs hierarchy
- * @kdops: optional directory syscall operations for the hierarchy
+ * @scops: optional syscall operations for the hierarchy
+ * @flags: KERNFS_ROOT_* flags
* @priv: opaque data associated with the new directory
*
* Returns the root of the new hierarchy on success, ERR_PTR() value on
* failure.
*/
-struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv)
+struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
+ unsigned int flags, void *priv)
{
struct kernfs_root *root;
struct kernfs_node *kn;
return ERR_PTR(-ENOMEM);
}
- kn->flags &= ~KERNFS_REMOVED;
kn->priv = priv;
kn->dir.root = root;
- root->dir_ops = kdops;
+ root->syscall_ops = scops;
+ root->flags = flags;
root->kn = kn;
+ init_waitqueue_head(&root->deactivate_waitq);
+
+ if (!(root->flags & KERNFS_ROOT_CREATE_DEACTIVATED))
+ kernfs_activate(kn);
return root;
}
const char *name, umode_t mode,
void *priv, const void *ns)
{
- struct kernfs_addrm_cxt acxt;
struct kernfs_node *kn;
int rc;
kn->priv = priv;
/* link in */
- kernfs_addrm_start(&acxt);
- rc = kernfs_add_one(&acxt, kn);
- kernfs_addrm_finish(&acxt);
-
+ rc = kernfs_add_one(kn);
if (!rc)
return kn;
kn = kernfs_find_ns(parent, dentry->d_name.name, ns);
/* no such entry */
- if (!kn) {
+ if (!kn || !kernfs_active(kn)) {
ret = NULL;
goto out_unlock;
}
umode_t mode)
{
struct kernfs_node *parent = dir->i_private;
- struct kernfs_dir_ops *kdops = kernfs_root(parent)->dir_ops;
+ struct kernfs_syscall_ops *scops = kernfs_root(parent)->syscall_ops;
+ int ret;
- if (!kdops || !kdops->mkdir)
+ if (!scops || !scops->mkdir)
return -EPERM;
- return kdops->mkdir(parent, dentry->d_name.name, mode);
+ if (!kernfs_get_active(parent))
+ return -ENODEV;
+
+ ret = scops->mkdir(parent, dentry->d_name.name, mode);
+
+ kernfs_put_active(parent);
+ return ret;
}
static int kernfs_iop_rmdir(struct inode *dir, struct dentry *dentry)
{
struct kernfs_node *kn = dentry->d_fsdata;
- struct kernfs_dir_ops *kdops = kernfs_root(kn)->dir_ops;
+ struct kernfs_syscall_ops *scops = kernfs_root(kn)->syscall_ops;
+ int ret;
- if (!kdops || !kdops->rmdir)
+ if (!scops || !scops->rmdir)
return -EPERM;
- return kdops->rmdir(kn);
+ if (!kernfs_get_active(kn))
+ return -ENODEV;
+
+ ret = scops->rmdir(kn);
+
+ kernfs_put_active(kn);
+ return ret;
}
static int kernfs_iop_rename(struct inode *old_dir, struct dentry *old_dentry,
{
struct kernfs_node *kn = old_dentry->d_fsdata;
struct kernfs_node *new_parent = new_dir->i_private;
- struct kernfs_dir_ops *kdops = kernfs_root(kn)->dir_ops;
+ struct kernfs_syscall_ops *scops = kernfs_root(kn)->syscall_ops;
+ int ret;
- if (!kdops || !kdops->rename)
+ if (!scops || !scops->rename)
return -EPERM;
- return kdops->rename(kn, new_parent, new_dentry->d_name.name);
+ if (!kernfs_get_active(kn))
+ return -ENODEV;
+
+ if (!kernfs_get_active(new_parent)) {
+ kernfs_put_active(kn);
+ return -ENODEV;
+ }
+
+ ret = scops->rename(kn, new_parent, new_dentry->d_name.name);
+
+ kernfs_put_active(new_parent);
+ kernfs_put_active(kn);
+ return ret;
}
const struct inode_operations kernfs_dir_iops = {
return pos->parent;
}
-static void __kernfs_remove(struct kernfs_addrm_cxt *acxt,
- struct kernfs_node *kn)
+/**
+ * kernfs_activate - activate a node which started deactivated
+ * @kn: kernfs_node whose subtree is to be activated
+ *
+ * If the root has KERNFS_ROOT_CREATE_DEACTIVATED set, a newly created node
+ * needs to be explicitly activated. A node which hasn't been activated
+ * isn't visible to userland and deactivation is skipped during its
+ * removal. This is useful to construct atomic init sequences where
+ * creation of multiple nodes should either succeed or fail atomically.
+ *
+ * The caller is responsible for ensuring that this function is not called
+ * after kernfs_remove*() is invoked on @kn.
+ */
+void kernfs_activate(struct kernfs_node *kn)
{
- struct kernfs_node *pos, *next;
+ struct kernfs_node *pos;
- if (!kn)
+ mutex_lock(&kernfs_mutex);
+
+ pos = NULL;
+ while ((pos = kernfs_next_descendant_post(pos, kn))) {
+ if (!pos || (pos->flags & KERNFS_ACTIVATED))
+ continue;
+
+ WARN_ON_ONCE(pos->parent && RB_EMPTY_NODE(&pos->rb));
+ WARN_ON_ONCE(atomic_read(&pos->active) != KN_DEACTIVATED_BIAS);
+
+ atomic_sub(KN_DEACTIVATED_BIAS, &pos->active);
+ pos->flags |= KERNFS_ACTIVATED;
+ }
+
+ mutex_unlock(&kernfs_mutex);
+}
+
+static void __kernfs_remove(struct kernfs_node *kn)
+{
+ struct kernfs_node *pos;
+
+ lockdep_assert_held(&kernfs_mutex);
+
+ /*
+ * Short-circuit if non-root @kn has already finished removal.
+ * This is for kernfs_remove_self() which plays with active ref
+ * after removal.
+ */
+ if (!kn || (kn->parent && RB_EMPTY_NODE(&kn->rb)))
return;
pr_debug("kernfs %s: removing\n", kn->name);
- next = NULL;
+ /* prevent any new usage under @kn by deactivating all nodes */
+ pos = NULL;
+ while ((pos = kernfs_next_descendant_post(pos, kn)))
+ if (kernfs_active(pos))
+ atomic_add(KN_DEACTIVATED_BIAS, &pos->active);
+
+ /* deactivate and unlink the subtree node-by-node */
do {
- pos = next;
- next = kernfs_next_descendant_post(pos, kn);
- if (pos)
- kernfs_remove_one(acxt, pos);
- } while (next);
+ pos = kernfs_leftmost_descendant(kn);
+
+ /*
+ * kernfs_drain() drops kernfs_mutex temporarily and @pos's
+ * base ref could have been put by someone else by the time
+ * the function returns. Make sure it doesn't go away
+ * underneath us.
+ */
+ kernfs_get(pos);
+
+ /*
+ * Drain iff @kn was activated. This avoids draining and
+ * its lockdep annotations for nodes which have never been
+ * activated and allows embedding kernfs_remove() in create
+ * error paths without worrying about draining.
+ */
+ if (kn->flags & KERNFS_ACTIVATED)
+ kernfs_drain(pos);
+ else
+ WARN_ON_ONCE(atomic_read(&kn->active) != KN_DEACTIVATED_BIAS);
+
+ /*
+ * kernfs_unlink_sibling() succeeds once per node. Use it
+ * to decide who's responsible for cleanups.
+ */
+ if (!pos->parent || kernfs_unlink_sibling(pos)) {
+ struct kernfs_iattrs *ps_iattr =
+ pos->parent ? pos->parent->iattr : NULL;
+
+ /* update timestamps on the parent */
+ if (ps_iattr) {
+ ps_iattr->ia_iattr.ia_ctime = CURRENT_TIME;
+ ps_iattr->ia_iattr.ia_mtime = CURRENT_TIME;
+ }
+
+ kernfs_put(pos);
+ }
+
+ kernfs_put(pos);
+ } while (pos != kn);
}
/**
*/
void kernfs_remove(struct kernfs_node *kn)
{
- struct kernfs_addrm_cxt acxt;
+ mutex_lock(&kernfs_mutex);
+ __kernfs_remove(kn);
+ mutex_unlock(&kernfs_mutex);
+}
- kernfs_addrm_start(&acxt);
- __kernfs_remove(&acxt, kn);
- kernfs_addrm_finish(&acxt);
+/**
+ * kernfs_break_active_protection - break out of active protection
+ * @kn: the self kernfs_node
+ *
+ * The caller must be running off of a kernfs operation which is invoked
+ * with an active reference - e.g. one of kernfs_ops. Each invocation of
+ * this function must also be matched with an invocation of
+ * kernfs_unbreak_active_protection().
+ *
+ * This function releases the active reference of @kn the caller is
+ * holding. Once this function is called, @kn may be removed at any point
+ * and the caller is solely responsible for ensuring that the objects it
+ * dereferences are accessible.
+ */
+void kernfs_break_active_protection(struct kernfs_node *kn)
+{
+ /*
+ * Take out ourself out of the active ref dependency chain. If
+ * we're called without an active ref, lockdep will complain.
+ */
+ kernfs_put_active(kn);
+}
+
+/**
+ * kernfs_unbreak_active_protection - undo kernfs_break_active_protection()
+ * @kn: the self kernfs_node
+ *
+ * If kernfs_break_active_protection() was called, this function must be
+ * invoked before finishing the kernfs operation. Note that while this
+ * function restores the active reference, it doesn't and can't actually
+ * restore the active protection - @kn may already or be in the process of
+ * being removed. Once kernfs_break_active_protection() is invoked, that
+ * protection is irreversibly gone for the kernfs operation instance.
+ *
+ * While this function may be called at any point after
+ * kernfs_break_active_protection() is invoked, its most useful location
+ * would be right before the enclosing kernfs operation returns.
+ */
+void kernfs_unbreak_active_protection(struct kernfs_node *kn)
+{
+ /*
+ * @kn->active could be in any state; however, the increment we do
+ * here will be undone as soon as the enclosing kernfs operation
+ * finishes and this temporary bump can't break anything. If @kn
+ * is alive, nothing changes. If @kn is being deactivated, the
+ * soon-to-follow put will either finish deactivation or restore
+ * deactivated state. If @kn is already removed, the temporary
+ * bump is guaranteed to be gone before @kn is released.
+ */
+ atomic_inc(&kn->active);
+ if (kernfs_lockdep(kn))
+ rwsem_acquire(&kn->dep_map, 0, 1, _RET_IP_);
+}
+
+/**
+ * kernfs_remove_self - remove a kernfs_node from its own method
+ * @kn: the self kernfs_node to remove
+ *
+ * The caller must be running off of a kernfs operation which is invoked
+ * with an active reference - e.g. one of kernfs_ops. This can be used to
+ * implement a file operation which deletes itself.
+ *
+ * For example, the "delete" file for a sysfs device directory can be
+ * implemented by invoking kernfs_remove_self() on the "delete" file
+ * itself. This function breaks the circular dependency of trying to
+ * deactivate self while holding an active ref itself. It isn't necessary
+ * to modify the usual removal path to use kernfs_remove_self(). The
+ * "delete" implementation can simply invoke kernfs_remove_self() on self
+ * before proceeding with the usual removal path. kernfs will ignore later
+ * kernfs_remove() on self.
+ *
+ * kernfs_remove_self() can be called multiple times concurrently on the
+ * same kernfs_node. Only the first one actually performs removal and
+ * returns %true. All others will wait until the kernfs operation which
+ * won self-removal finishes and return %false. Note that the losers wait
+ * for the completion of not only the winning kernfs_remove_self() but also
+ * the whole kernfs_ops which won the arbitration. This can be used to
+ * guarantee, for example, all concurrent writes to a "delete" file to
+ * finish only after the whole operation is complete.
+ */
+bool kernfs_remove_self(struct kernfs_node *kn)
+{
+ bool ret;
+
+ mutex_lock(&kernfs_mutex);
+ kernfs_break_active_protection(kn);
+
+ /*
+ * SUICIDAL is used to arbitrate among competing invocations. Only
+ * the first one will actually perform removal. When the removal
+ * is complete, SUICIDED is set and the active ref is restored
+ * while holding kernfs_mutex. The ones which lost arbitration
+ * waits for SUICDED && drained which can happen only after the
+ * enclosing kernfs operation which executed the winning instance
+ * of kernfs_remove_self() finished.
+ */
+ if (!(kn->flags & KERNFS_SUICIDAL)) {
+ kn->flags |= KERNFS_SUICIDAL;
+ __kernfs_remove(kn);
+ kn->flags |= KERNFS_SUICIDED;
+ ret = true;
+ } else {
+ wait_queue_head_t *waitq = &kernfs_root(kn)->deactivate_waitq;
+ DEFINE_WAIT(wait);
+
+ while (true) {
+ prepare_to_wait(waitq, &wait, TASK_UNINTERRUPTIBLE);
+
+ if ((kn->flags & KERNFS_SUICIDED) &&
+ atomic_read(&kn->active) == KN_DEACTIVATED_BIAS)
+ break;
+
+ mutex_unlock(&kernfs_mutex);
+ schedule();
+ mutex_lock(&kernfs_mutex);
+ }
+ finish_wait(waitq, &wait);
+ WARN_ON_ONCE(!RB_EMPTY_NODE(&kn->rb));
+ ret = false;
+ }
+
+ /*
+ * This must be done while holding kernfs_mutex; otherwise, waiting
+ * for SUICIDED && deactivated could finish prematurely.
+ */
+ kernfs_unbreak_active_protection(kn);
+
+ mutex_unlock(&kernfs_mutex);
+ return ret;
}
/**
int kernfs_remove_by_name_ns(struct kernfs_node *parent, const char *name,
const void *ns)
{
- struct kernfs_addrm_cxt acxt;
struct kernfs_node *kn;
if (!parent) {
return -ENOENT;
}
- kernfs_addrm_start(&acxt);
+ mutex_lock(&kernfs_mutex);
kn = kernfs_find_ns(parent, name, ns);
if (kn)
- __kernfs_remove(&acxt, kn);
+ __kernfs_remove(kn);
- kernfs_addrm_finish(&acxt);
+ mutex_unlock(&kernfs_mutex);
if (kn)
return 0;
int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
const char *new_name, const void *new_ns)
{
+ struct kernfs_node *old_parent;
+ const char *old_name = NULL;
int error;
+ /* can't move or rename root */
+ if (!kn->parent)
+ return -EINVAL;
+
mutex_lock(&kernfs_mutex);
error = -ENOENT;
- if ((kn->flags | new_parent->flags) & KERNFS_REMOVED)
+ if (!kernfs_active(kn) || !kernfs_active(new_parent))
goto out;
error = 0;
new_name = kstrdup(new_name, GFP_KERNEL);
if (!new_name)
goto out;
-
- if (kn->flags & KERNFS_STATIC_NAME)
- kn->flags &= ~KERNFS_STATIC_NAME;
- else
- kfree(kn->name);
-
- kn->name = new_name;
+ } else {
+ new_name = NULL;
}
/*
*/
kernfs_unlink_sibling(kn);
kernfs_get(new_parent);
- kernfs_put(kn->parent);
+
+ /* rename_lock protects ->parent and ->name accessors */
+ spin_lock_irq(&kernfs_rename_lock);
+
+ old_parent = kn->parent;
+ kn->parent = new_parent;
+
kn->ns = new_ns;
+ if (new_name) {
+ if (!(kn->flags & KERNFS_STATIC_NAME))
+ old_name = kn->name;
+ kn->flags &= ~KERNFS_STATIC_NAME;
+ kn->name = new_name;
+ }
+
+ spin_unlock_irq(&kernfs_rename_lock);
+
kn->hash = kernfs_name_hash(kn->name, kn->ns);
- kn->parent = new_parent;
kernfs_link_sibling(kn);
+ kernfs_put(old_parent);
+ kfree(old_name);
+
error = 0;
out:
mutex_unlock(&kernfs_mutex);
struct kernfs_node *parent, loff_t hash, struct kernfs_node *pos)
{
if (pos) {
- int valid = !(pos->flags & KERNFS_REMOVED) &&
+ int valid = kernfs_active(pos) &&
pos->parent == parent && hash == pos->hash;
kernfs_put(pos);
if (!valid)
break;
}
}
- /* Skip over entries in the wrong namespace */
- while (pos && pos->ns != ns) {
+ /* Skip over entries which are dying/dead or in the wrong namespace */
+ while (pos && (!kernfs_active(pos) || pos->ns != ns)) {
struct rb_node *node = rb_next(&pos->rb);
if (!node)
pos = NULL;
struct kernfs_node *parent, ino_t ino, struct kernfs_node *pos)
{
pos = kernfs_dir_pos(ns, parent, ino, pos);
- if (pos)
+ if (pos) {
do {
struct rb_node *node = rb_next(&pos->rb);
if (!node)
pos = NULL;
else
pos = rb_to_kn(node);
- } while (pos && pos->ns != ns);
+ } while (pos && (!kernfs_active(pos) || pos->ns != ns));
+ }
return pos;
}
size_t count, loff_t *ppos)
{
struct kernfs_open_file *of = kernfs_of(file);
- ssize_t len = min_t(size_t, count, PAGE_SIZE);
const struct kernfs_ops *ops;
+ size_t len;
char *buf;
+ if (of->atomic_write_len) {
+ len = count;
+ if (len > of->atomic_write_len)
+ return -E2BIG;
+ } else {
+ len = min_t(size_t, count, PAGE_SIZE);
+ }
+
buf = kmalloc(len + 1, GFP_KERNEL);
if (!buf)
return -ENOMEM;
of->kn = kn;
of->file = file;
+ /*
+ * Write path needs to atomic_write_len outside active reference.
+ * Cache it in open_file. See kernfs_fop_write() for details.
+ */
+ of->atomic_write_len = ops->atomic_write_len;
+
/*
* Always instantiate seq_file even if read access doesn't use
* seq_file or is not requested. This unifies private data access
bool name_is_static,
struct lock_class_key *key)
{
- struct kernfs_addrm_cxt acxt;
struct kernfs_node *kn;
unsigned flags;
int rc;
if (ops->mmap)
kn->flags |= KERNFS_HAS_MMAP;
- kernfs_addrm_start(&acxt);
- rc = kernfs_add_one(&acxt, kn);
- kernfs_addrm_finish(&acxt);
-
+ rc = kernfs_add_one(kn);
if (rc) {
kernfs_put(kn);
return ERR_PTR(rc);
struct simple_xattrs xattrs;
};
-#define KN_DEACTIVATED_BIAS INT_MIN
+/* +1 to avoid triggering overflow warning when negating it */
+#define KN_DEACTIVATED_BIAS (INT_MIN + 1)
/* KERNFS_TYPE_MASK and types are defined in include/linux/kernfs.h */
return kn->dir.root;
}
-/*
- * Context structure to be used while adding/removing nodes.
- */
-struct kernfs_addrm_cxt {
- struct kernfs_node *removed;
-};
-
/*
* mount.c
*/
};
#define kernfs_info(SB) ((struct kernfs_super_info *)(SB->s_fs_info))
+extern const struct super_operations kernfs_sops;
extern struct kmem_cache *kernfs_node_cache;
/*
struct kernfs_node *kernfs_get_active(struct kernfs_node *kn);
void kernfs_put_active(struct kernfs_node *kn);
-void kernfs_addrm_start(struct kernfs_addrm_cxt *acxt);
-int kernfs_add_one(struct kernfs_addrm_cxt *acxt, struct kernfs_node *kn);
-void kernfs_addrm_finish(struct kernfs_addrm_cxt *acxt);
+int kernfs_add_one(struct kernfs_node *kn);
struct kernfs_node *kernfs_new_node(struct kernfs_node *parent,
const char *name, umode_t mode,
unsigned flags);
struct kmem_cache *kernfs_node_cache;
-static const struct super_operations kernfs_sops = {
+static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data)
+{
+ struct kernfs_root *root = kernfs_info(sb)->root;
+ struct kernfs_syscall_ops *scops = root->syscall_ops;
+
+ if (scops && scops->remount_fs)
+ return scops->remount_fs(root, flags, data);
+ return 0;
+}
+
+static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry)
+{
+ struct kernfs_root *root = kernfs_root(dentry->d_fsdata);
+ struct kernfs_syscall_ops *scops = root->syscall_ops;
+
+ if (scops && scops->show_options)
+ return scops->show_options(sf, root);
+ return 0;
+}
+
+const struct super_operations kernfs_sops = {
.statfs = simple_statfs,
.drop_inode = generic_delete_inode,
.evict_inode = kernfs_evict_inode,
+
+ .remount_fs = kernfs_sop_remount_fs,
+ .show_options = kernfs_sop_show_options,
};
+/**
+ * kernfs_root_from_sb - determine kernfs_root associated with a super_block
+ * @sb: the super_block in question
+ *
+ * Return the kernfs_root associated with @sb. If @sb is not a kernfs one,
+ * %NULL is returned.
+ */
+struct kernfs_root *kernfs_root_from_sb(struct super_block *sb)
+{
+ if (sb->s_op == &kernfs_sops)
+ return kernfs_info(sb)->root;
+ return NULL;
+}
+
static int kernfs_fill_super(struct super_block *sb)
{
struct kernfs_super_info *info = kernfs_info(sb);
struct kernfs_node *target)
{
struct kernfs_node *kn;
- struct kernfs_addrm_cxt acxt;
int error;
kn = kernfs_new_node(parent, name, S_IFLNK|S_IRWXUGO, KERNFS_LINK);
kn->symlink.target_kn = target;
kernfs_get(target); /* ref owned by symlink */
- kernfs_addrm_start(&acxt);
- error = kernfs_add_one(&acxt, kn);
- kernfs_addrm_finish(&acxt);
-
+ error = kernfs_add_one(kn);
if (!error)
return kn;
config SYSFS
bool "sysfs file system support" if EXPERT
default y
+ select KERNFS
help
The sysfs filesystem is a virtual filesystem that the kernel uses to
export internal kernel objects, their attributes, and their
DEFINE_SPINLOCK(sysfs_symlink_target_lock);
-/**
- * sysfs_pathname - return full path to sysfs dirent
- * @kn: kernfs_node whose path we want
- * @path: caller allocated buffer of size PATH_MAX
- *
- * Gives the name "/" to the sysfs_root entry; any path returned
- * is relative to wherever sysfs is mounted.
- */
-static char *sysfs_pathname(struct kernfs_node *kn, char *path)
-{
- if (kn->parent) {
- sysfs_pathname(kn->parent, path);
- strlcat(path, "/", PATH_MAX);
- }
- strlcat(path, kn->name, PATH_MAX);
- return path;
-}
-
void sysfs_warn_dup(struct kernfs_node *parent, const char *name)
{
- char *path;
+ char *buf, *path = NULL;
- path = kzalloc(PATH_MAX, GFP_KERNEL);
- if (path) {
- sysfs_pathname(parent, path);
- strlcat(path, "/", PATH_MAX);
- strlcat(path, name, PATH_MAX);
- }
+ buf = kzalloc(PATH_MAX, GFP_KERNEL);
+ if (buf)
+ path = kernfs_path(parent, buf, PATH_MAX);
- WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s'\n",
- path ? path : name);
+ WARN(1, KERN_WARNING "sysfs: cannot create duplicate filename '%s/%s'\n",
+ path, name);
- kfree(path);
+ kfree(buf);
}
/**
int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
const void *new_ns)
{
- struct kernfs_node *parent = kobj->sd->parent;
+ struct kernfs_node *parent;
+ int ret;
- return kernfs_rename_ns(kobj->sd, parent, new_name, new_ns);
+ parent = kernfs_get_parent(kobj->sd);
+ ret = kernfs_rename_ns(kobj->sd, parent, new_name, new_ns);
+ kernfs_put(parent);
+ return ret;
}
int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj,
struct kernfs_node *kn = kobj->sd;
struct kernfs_node *new_parent;
- BUG_ON(!kn->parent);
new_parent = new_parent_kobj && new_parent_kobj->sd ?
new_parent_kobj->sd : sysfs_root_kn;
}
EXPORT_SYMBOL_GPL(sysfs_remove_file_ns);
+/**
+ * sysfs_remove_file_self - remove an object attribute from its own method
+ * @kobj: object we're acting for
+ * @attr: attribute descriptor
+ *
+ * See kernfs_remove_self() for details.
+ */
+bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr)
+{
+ struct kernfs_node *parent = kobj->sd;
+ struct kernfs_node *kn;
+ bool ret;
+
+ kn = kernfs_find_and_get(parent, attr->name);
+ if (WARN_ON_ONCE(!kn))
+ return false;
+
+ ret = kernfs_remove_self(kn);
+
+ kernfs_put(kn);
+ return ret;
+}
+
void sysfs_remove_files(struct kobject *kobj, const struct attribute **ptr)
{
int i;
if (grp->bin_attrs) {
for (bin_attr = grp->bin_attrs; *bin_attr; bin_attr++) {
if (update)
- sysfs_remove_bin_file(kobj, *bin_attr);
- error = sysfs_create_bin_file(kobj, *bin_attr);
+ kernfs_remove_by_name(parent,
+ (*bin_attr)->attr.name);
+ error = sysfs_add_file_mode_ns(parent,
+ &(*bin_attr)->attr, true,
+ (*bin_attr)->attr.mode, NULL);
if (error)
break;
}
{
int err;
- sysfs_root = kernfs_create_root(NULL, NULL);
+ sysfs_root = kernfs_create_root(NULL, 0, NULL);
if (IS_ERR(sysfs_root))
return PTR_ERR(sysfs_root);
#endif
struct notifier_block;
-#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
-extern int arch_cpu_uevent(struct device *dev, struct kobj_uevent_env *env);
-extern ssize_t arch_print_cpu_modalias(struct device *dev,
- struct device_attribute *attr,
- char *bufptr);
-#endif
-
/*
* CPU notifier priorities.
*/
--- /dev/null
+/*
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_CPUFEATURE_H
+#define __LINUX_CPUFEATURE_H
+
+#ifdef CONFIG_GENERIC_CPU_AUTOPROBE
+
+#include <linux/mod_devicetable.h>
+#include <asm/cpufeature.h>
+
+/*
+ * Macros imported from <asm/cpufeature.h>:
+ * - cpu_feature(x) ordinal value of feature called 'x'
+ * - cpu_have_feature(u32 n) whether feature #n is available
+ * - MAX_CPU_FEATURES upper bound for feature ordinal values
+ * Optional:
+ * - CPU_FEATURE_TYPEFMT format string fragment for printing the cpu type
+ * - CPU_FEATURE_TYPEVAL set of values matching the format string above
+ */
+
+#ifndef CPU_FEATURE_TYPEFMT
+#define CPU_FEATURE_TYPEFMT "%s"
+#endif
+
+#ifndef CPU_FEATURE_TYPEVAL
+#define CPU_FEATURE_TYPEVAL ELF_PLATFORM
+#endif
+
+/*
+ * Use module_cpu_feature_match(feature, module_init_function) to
+ * declare that
+ * a) the module shall be probed upon discovery of CPU feature 'feature'
+ * (typically at boot time using udev)
+ * b) the module must not be loaded if CPU feature 'feature' is not present
+ * (not even by manual insmod).
+ *
+ * For a list of legal values for 'feature', please consult the file
+ * 'asm/cpufeature.h' of your favorite architecture.
+ */
+#define module_cpu_feature_match(x, __init) \
+static struct cpu_feature const cpu_feature_match_ ## x[] = \
+ { { .feature = cpu_feature(x) }, { } }; \
+MODULE_DEVICE_TABLE(cpu, cpu_feature_match_ ## x); \
+ \
+static int cpu_feature_match_ ## x ## _init(void) \
+{ \
+ if (!cpu_have_feature(cpu_feature(x))) \
+ return -ENODEV; \
+ return __init(); \
+} \
+module_init(cpu_feature_match_ ## x ## _init)
+
+#endif
+#endif
const struct device_attribute *entry);
extern void device_remove_file(struct device *dev,
const struct device_attribute *attr);
+extern bool device_remove_file_self(struct device *dev,
+ const struct device_attribute *attr);
extern int __must_check device_create_bin_file(struct device *dev,
const struct bin_attribute *attr);
extern void device_remove_bin_file(struct device *dev,
#include <linux/lockdep.h>
#include <linux/rbtree.h>
#include <linux/atomic.h>
-#include <linux/completion.h>
+#include <linux/wait.h>
struct file;
struct dentry;
};
#define KERNFS_TYPE_MASK 0x000f
-#define KERNFS_ACTIVE_REF KERNFS_FILE
#define KERNFS_FLAG_MASK ~KERNFS_TYPE_MASK
enum kernfs_node_flag {
- KERNFS_REMOVED = 0x0010,
+ KERNFS_ACTIVATED = 0x0010,
KERNFS_NS = 0x0020,
KERNFS_HAS_SEQ_SHOW = 0x0040,
KERNFS_HAS_MMAP = 0x0080,
KERNFS_LOCKDEP = 0x0100,
KERNFS_STATIC_NAME = 0x0200,
+ KERNFS_SUICIDAL = 0x0400,
+ KERNFS_SUICIDED = 0x0800,
+};
+
+/* @flags for kernfs_create_root() */
+enum kernfs_root_flag {
+ KERNFS_ROOT_CREATE_DEACTIVATED = 0x0001,
};
/* type-specific structures for kernfs_node union members */
#ifdef CONFIG_DEBUG_LOCK_ALLOC
struct lockdep_map dep_map;
#endif
- /* the following two fields are published */
+ /*
+ * Use kernfs_get_parent() and kernfs_name/path() instead of
+ * accessing the following two fields directly. If the node is
+ * never moved to a different parent, it is safe to access the
+ * parent directly.
+ */
struct kernfs_node *parent;
const char *name;
struct rb_node rb;
- union {
- struct completion *completion;
- struct kernfs_node *removed_list;
- } u;
-
const void *ns; /* namespace tag */
unsigned int hash; /* ns + name hash */
union {
};
/*
- * kernfs_dir_ops may be specified on kernfs_create_root() to support
- * directory manipulation syscalls. These optional callbacks are invoked
- * on the matching syscalls and can perform any kernfs operations which
- * don't necessarily have to be the exact operation requested.
+ * kernfs_syscall_ops may be specified on kernfs_create_root() to support
+ * syscalls. These optional callbacks are invoked on the matching syscalls
+ * and can perform any kernfs operations which don't necessarily have to be
+ * the exact operation requested. An active reference is held for each
+ * kernfs_node parameter.
*/
-struct kernfs_dir_ops {
+struct kernfs_syscall_ops {
+ int (*remount_fs)(struct kernfs_root *root, int *flags, char *data);
+ int (*show_options)(struct seq_file *sf, struct kernfs_root *root);
+
int (*mkdir)(struct kernfs_node *parent, const char *name,
umode_t mode);
int (*rmdir)(struct kernfs_node *kn);
struct kernfs_root {
/* published fields */
struct kernfs_node *kn;
+ unsigned int flags; /* KERNFS_ROOT_* flags */
/* private fields, do not use outside kernfs proper */
struct ida ino_ida;
- struct kernfs_dir_ops *dir_ops;
+ struct kernfs_syscall_ops *syscall_ops;
+ wait_queue_head_t deactivate_waitq;
};
struct kernfs_open_file {
/* published fields */
struct kernfs_node *kn;
struct file *file;
+ void *priv;
/* private fields, do not use outside kernfs proper */
struct mutex mutex;
int event;
struct list_head list;
+ size_t atomic_write_len;
bool mmapped;
const struct vm_operations_struct *vm_ops;
};
loff_t off);
/*
- * write() is bounced through kernel buffer and a write larger than
- * PAGE_SIZE results in partial operation of PAGE_SIZE.
+ * write() is bounced through kernel buffer. If atomic_write_len
+ * is not set, a write larger than PAGE_SIZE results in partial
+ * operations of PAGE_SIZE chunks. If atomic_write_len is set,
+ * writes upto the specified size are executed atomically but
+ * larger ones are rejected with -E2BIG.
*/
+ size_t atomic_write_len;
ssize_t (*write)(struct kernfs_open_file *of, char *buf, size_t bytes,
loff_t off);
#endif
};
-#ifdef CONFIG_SYSFS
+#ifdef CONFIG_KERNFS
static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn)
{
return kn->flags & KERNFS_NS;
}
+int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen);
+char * __must_check kernfs_path(struct kernfs_node *kn, char *buf,
+ size_t buflen);
+void pr_cont_kernfs_name(struct kernfs_node *kn);
+void pr_cont_kernfs_path(struct kernfs_node *kn);
+struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn);
struct kernfs_node *kernfs_find_and_get_ns(struct kernfs_node *parent,
const char *name, const void *ns);
void kernfs_get(struct kernfs_node *kn);
void kernfs_put(struct kernfs_node *kn);
-struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops,
- void *priv);
+struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry);
+struct kernfs_root *kernfs_root_from_sb(struct super_block *sb);
+
+struct kernfs_root *kernfs_create_root(struct kernfs_syscall_ops *scops,
+ unsigned int flags, void *priv);
void kernfs_destroy_root(struct kernfs_root *root);
struct kernfs_node *kernfs_create_dir_ns(struct kernfs_node *parent,
struct kernfs_node *kernfs_create_link(struct kernfs_node *parent,
const char *name,
struct kernfs_node *target);
+void kernfs_activate(struct kernfs_node *kn);
void kernfs_remove(struct kernfs_node *kn);
+void kernfs_break_active_protection(struct kernfs_node *kn);
+void kernfs_unbreak_active_protection(struct kernfs_node *kn);
+bool kernfs_remove_self(struct kernfs_node *kn);
int kernfs_remove_by_name_ns(struct kernfs_node *parent, const char *name,
const void *ns);
int kernfs_rename_ns(struct kernfs_node *kn, struct kernfs_node *new_parent,
void kernfs_init(void);
-#else /* CONFIG_SYSFS */
+#else /* CONFIG_KERNFS */
static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn)
{ return 0; } /* whatever */
static inline bool kernfs_ns_enabled(struct kernfs_node *kn)
{ return false; }
+static inline int kernfs_name(struct kernfs_node *kn, char *buf, size_t buflen)
+{ return -ENOSYS; }
+
+static inline char * __must_check kernfs_path(struct kernfs_node *kn, char *buf,
+ size_t buflen)
+{ return NULL; }
+
+static inline void pr_cont_kernfs_name(struct kernfs_node *kn) { }
+static inline void pr_cont_kernfs_path(struct kernfs_node *kn) { }
+
+static inline struct kernfs_node *kernfs_get_parent(struct kernfs_node *kn)
+{ return NULL; }
+
static inline struct kernfs_node *
kernfs_find_and_get_ns(struct kernfs_node *parent, const char *name,
const void *ns)
static inline void kernfs_get(struct kernfs_node *kn) { }
static inline void kernfs_put(struct kernfs_node *kn) { }
+static inline struct kernfs_node *kernfs_node_from_dentry(struct dentry *dentry)
+{ return NULL; }
+
+static inline struct kernfs_root *kernfs_root_from_sb(struct super_block *sb)
+{ return NULL; }
+
static inline struct kernfs_root *
-kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv)
+kernfs_create_root(struct kernfs_syscall_ops *scops, unsigned int flags,
+ void *priv)
{ return ERR_PTR(-ENOSYS); }
static inline void kernfs_destroy_root(struct kernfs_root *root) { }
struct kernfs_node *target)
{ return ERR_PTR(-ENOSYS); }
+static inline void kernfs_activate(struct kernfs_node *kn) { }
+
static inline void kernfs_remove(struct kernfs_node *kn) { }
+static inline bool kernfs_remove_self(struct kernfs_node *kn)
+{ return false; }
+
static inline int kernfs_remove_by_name_ns(struct kernfs_node *kn,
const char *name, const void *ns)
{ return -ENOSYS; }
static inline void kernfs_init(void) { }
-#endif /* CONFIG_SYSFS */
+#endif /* CONFIG_KERNFS */
static inline struct kernfs_node *
kernfs_find_and_get(struct kernfs_node *kn, const char *name)
return kernfs_remove_by_name_ns(parent, name, NULL);
}
+static inline int kernfs_rename(struct kernfs_node *kn,
+ struct kernfs_node *new_parent,
+ const char *new_name)
+{
+ return kernfs_rename_ns(kn, new_parent, new_name, NULL);
+}
+
static inline struct dentry *
kernfs_mount(struct file_system_type *fs_type, int flags,
struct kernfs_root *root, bool *new_sb_created)
#define X86_MODEL_ANY 0
#define X86_FEATURE_ANY 0 /* Same as FPU, you can't test for that */
+/*
+ * Generic table type for matching CPU features.
+ * @feature: the bit number of the feature (0 - 65535)
+ */
+
+struct cpu_feature {
+ __u16 feature;
+};
+
#define IPACK_ANY_FORMAT 0xff
#define IPACK_ANY_ID (~0)
struct ipack_device_id {
const struct attribute *attr, umode_t mode);
void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
const void *ns);
+bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
int __must_check sysfs_create_bin_file(struct kobject *kobj,
int __must_check sysfs_init(void);
+static inline void sysfs_enable_ns(struct kernfs_node *kn)
+{
+ return kernfs_enable_ns(kn);
+}
+
#else /* CONFIG_SYSFS */
static inline int sysfs_schedule_callback(struct kobject *kobj,
{
}
+static inline bool sysfs_remove_file_self(struct kobject *kobj,
+ const struct attribute *attr)
+{
+ return false;
+}
+
static inline void sysfs_remove_files(struct kobject *kobj,
const struct attribute **attr)
{
return 0;
}
+static inline void sysfs_enable_ns(struct kernfs_node *kn)
+{
+}
+
#endif /* CONFIG_SYSFS */
static inline int __must_check sysfs_create_file(struct kobject *kobj,
BUG_ON(ops->type >= KOBJ_NS_TYPES);
BUG_ON(!kobj_ns_type_registered(ops->type));
- kernfs_enable_ns(kobj->sd);
+ sysfs_enable_ns(kobj->sd);
}
return 0;
DEVID_FIELD(x86_cpu_id, model);
DEVID_FIELD(x86_cpu_id, vendor);
+ DEVID(cpu_feature);
+ DEVID_FIELD(cpu_feature, feature);
+
DEVID(mei_cl_device_id);
DEVID_FIELD(mei_cl_device_id, name);
}
ADD_TO_DEVTABLE("amba", amba_id, do_amba_entry);
-/* LOOKS like x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:*,FEAT,*
+/* LOOKS like cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:*,FEAT,*
* All fields are numbers. It would be nicer to use strings for vendor
* and feature, but getting those out of the build system here is too
* complicated.
DEF_FIELD(symval, x86_cpu_id, model);
DEF_FIELD(symval, x86_cpu_id, vendor);
- strcpy(alias, "x86cpu:");
- ADD(alias, "vendor:", vendor != X86_VENDOR_ANY, vendor);
- ADD(alias, ":family:", family != X86_FAMILY_ANY, family);
- ADD(alias, ":model:", model != X86_MODEL_ANY, model);
+ strcpy(alias, "cpu:type:x86,");
+ ADD(alias, "ven", vendor != X86_VENDOR_ANY, vendor);
+ ADD(alias, "fam", family != X86_FAMILY_ANY, family);
+ ADD(alias, "mod", model != X86_MODEL_ANY, model);
strcat(alias, ":feature:*");
if (feature != X86_FEATURE_ANY)
sprintf(alias + strlen(alias), "%04X*", feature);
}
ADD_TO_DEVTABLE("x86cpu", x86_cpu_id, do_x86cpu_entry);
+/* LOOKS like cpu:type:*:feature:*FEAT* */
+static int do_cpu_entry(const char *filename, void *symval, char *alias)
+{
+ DEF_FIELD(symval, cpu_feature, feature);
+
+ sprintf(alias, "cpu:type:*:feature:*%04X*", feature);
+ return 1;
+}
+ADD_TO_DEVTABLE("cpu", cpu_feature, do_cpu_entry);
+
/* Looks like: mei:S */
static int do_mei_entry(const char *filename, void *symval,
char *alias)
projects / linux-2.6-block.git / commitdiff