Merge branch 'for-4.9/dax' into libnvdimm-for-next

This commit is contained in:
Dan Williams 2016-10-07 16:46:30 -07:00
Родитель 178d6f4be8 4e65e9381c
Коммит e476f94482
7 изменённых файлов: 365 добавлений и 233 удалений

Просмотреть файл

@ -23,4 +23,9 @@ config DEV_DAX_PMEM
Say Y if unsure
config NR_DEV_DAX
int "Maximum number of Device-DAX instances"
default 32768
range 256 2147483647
endif

Просмотреть файл

@ -13,15 +13,25 @@
#include <linux/pagemap.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/mount.h>
#include <linux/pfn_t.h>
#include <linux/hash.h>
#include <linux/cdev.h>
#include <linux/slab.h>
#include <linux/dax.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include "dax.h"
static int dax_major;
static dev_t dax_devt;
static struct class *dax_class;
static DEFINE_IDA(dax_minor_ida);
static int nr_dax = CONFIG_NR_DEV_DAX;
module_param(nr_dax, int, S_IRUGO);
static struct vfsmount *dax_mnt;
static struct kmem_cache *dax_cache __read_mostly;
static struct super_block *dax_superblock __read_mostly;
MODULE_PARM_DESC(nr_dax, "max number of device-dax instances");
/**
* struct dax_region - mapping infrastructure for dax devices
@ -48,7 +58,7 @@ struct dax_region {
* struct dax_dev - subdivision of a dax region
* @region - parent region
* @dev - device backing the character device
* @kref - enable this data to be tracked in filp->private_data
* @cdev - core chardev data
* @alive - !alive + rcu grace period == no new mappings can be established
* @id - child id in the region
* @num_resources - number of physical address extents in this device
@ -56,14 +66,126 @@ struct dax_region {
*/
struct dax_dev {
struct dax_region *region;
struct device *dev;
struct kref kref;
struct inode *inode;
struct device dev;
struct cdev cdev;
bool alive;
int id;
int num_resources;
struct resource res[0];
};
static struct inode *dax_alloc_inode(struct super_block *sb)
{
return kmem_cache_alloc(dax_cache, GFP_KERNEL);
}
static void dax_i_callback(struct rcu_head *head)
{
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(dax_cache, inode);
}
static void dax_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, dax_i_callback);
}
static const struct super_operations dax_sops = {
.statfs = simple_statfs,
.alloc_inode = dax_alloc_inode,
.destroy_inode = dax_destroy_inode,
.drop_inode = generic_delete_inode,
};
static struct dentry *dax_mount(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
return mount_pseudo(fs_type, "dax:", &dax_sops, NULL, DAXFS_MAGIC);
}
static struct file_system_type dax_type = {
.name = "dax",
.mount = dax_mount,
.kill_sb = kill_anon_super,
};
static int dax_test(struct inode *inode, void *data)
{
return inode->i_cdev == data;
}
static int dax_set(struct inode *inode, void *data)
{
inode->i_cdev = data;
return 0;
}
static struct inode *dax_inode_get(struct cdev *cdev, dev_t devt)
{
struct inode *inode;
inode = iget5_locked(dax_superblock, hash_32(devt + DAXFS_MAGIC, 31),
dax_test, dax_set, cdev);
if (!inode)
return NULL;
if (inode->i_state & I_NEW) {
inode->i_mode = S_IFCHR;
inode->i_flags = S_DAX;
inode->i_rdev = devt;
mapping_set_gfp_mask(&inode->i_data, GFP_USER);
unlock_new_inode(inode);
}
return inode;
}
static void init_once(void *inode)
{
inode_init_once(inode);
}
static int dax_inode_init(void)
{
int rc;
dax_cache = kmem_cache_create("dax_cache", sizeof(struct inode), 0,
(SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
SLAB_MEM_SPREAD|SLAB_ACCOUNT),
init_once);
if (!dax_cache)
return -ENOMEM;
rc = register_filesystem(&dax_type);
if (rc)
goto err_register_fs;
dax_mnt = kern_mount(&dax_type);
if (IS_ERR(dax_mnt)) {
rc = PTR_ERR(dax_mnt);
goto err_mount;
}
dax_superblock = dax_mnt->mnt_sb;
return 0;
err_mount:
unregister_filesystem(&dax_type);
err_register_fs:
kmem_cache_destroy(dax_cache);
return rc;
}
static void dax_inode_exit(void)
{
kern_unmount(dax_mnt);
unregister_filesystem(&dax_type);
kmem_cache_destroy(dax_cache);
}
static void dax_region_free(struct kref *kref)
{
struct dax_region *dax_region;
@ -78,28 +200,17 @@ void dax_region_put(struct dax_region *dax_region)
}
EXPORT_SYMBOL_GPL(dax_region_put);
static void dax_dev_free(struct kref *kref)
{
struct dax_dev *dax_dev;
dax_dev = container_of(kref, struct dax_dev, kref);
dax_region_put(dax_dev->region);
kfree(dax_dev);
}
static void dax_dev_put(struct dax_dev *dax_dev)
{
kref_put(&dax_dev->kref, dax_dev_free);
}
struct dax_region *alloc_dax_region(struct device *parent, int region_id,
struct resource *res, unsigned int align, void *addr,
unsigned long pfn_flags)
{
struct dax_region *dax_region;
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
if (!IS_ALIGNED(res->start, align)
|| !IS_ALIGNED(resource_size(res), align))
return NULL;
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL);
if (!dax_region)
return NULL;
@ -116,10 +227,15 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
}
EXPORT_SYMBOL_GPL(alloc_dax_region);
static struct dax_dev *to_dax_dev(struct device *dev)
{
return container_of(dev, struct dax_dev, dev);
}
static ssize_t size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct dax_dev *dax_dev = dev_get_drvdata(dev);
struct dax_dev *dax_dev = to_dax_dev(dev);
unsigned long long size = 0;
int i;
@ -144,180 +260,11 @@ static const struct attribute_group *dax_attribute_groups[] = {
NULL,
};
static void unregister_dax_dev(void *_dev)
{
struct device *dev = _dev;
struct dax_dev *dax_dev = dev_get_drvdata(dev);
struct dax_region *dax_region = dax_dev->region;
dev_dbg(dev, "%s\n", __func__);
/*
* Note, rcu is not protecting the liveness of dax_dev, rcu is
* ensuring that any fault handlers that might have seen
* dax_dev->alive == true, have completed. Any fault handlers
* that start after synchronize_rcu() has started will abort
* upon seeing dax_dev->alive == false.
*/
dax_dev->alive = false;
synchronize_rcu();
get_device(dev);
device_unregister(dev);
ida_simple_remove(&dax_region->ida, dax_dev->id);
ida_simple_remove(&dax_minor_ida, MINOR(dev->devt));
put_device(dev);
dax_dev_put(dax_dev);
}
int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
int count)
{
struct device *parent = dax_region->dev;
struct dax_dev *dax_dev;
struct device *dev;
int rc, minor;
dev_t dev_t;
dax_dev = kzalloc(sizeof(*dax_dev) + sizeof(*res) * count, GFP_KERNEL);
if (!dax_dev)
return -ENOMEM;
memcpy(dax_dev->res, res, sizeof(*res) * count);
dax_dev->num_resources = count;
kref_init(&dax_dev->kref);
dax_dev->alive = true;
dax_dev->region = dax_region;
kref_get(&dax_region->kref);
dax_dev->id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
if (dax_dev->id < 0) {
rc = dax_dev->id;
goto err_id;
}
minor = ida_simple_get(&dax_minor_ida, 0, 0, GFP_KERNEL);
if (minor < 0) {
rc = minor;
goto err_minor;
}
dev_t = MKDEV(dax_major, minor);
dev = device_create_with_groups(dax_class, parent, dev_t, dax_dev,
dax_attribute_groups, "dax%d.%d", dax_region->id,
dax_dev->id);
if (IS_ERR(dev)) {
rc = PTR_ERR(dev);
goto err_create;
}
dax_dev->dev = dev;
rc = devm_add_action_or_reset(dax_region->dev, unregister_dax_dev, dev);
if (rc)
return rc;
return 0;
err_create:
ida_simple_remove(&dax_minor_ida, minor);
err_minor:
ida_simple_remove(&dax_region->ida, dax_dev->id);
err_id:
dax_dev_put(dax_dev);
return rc;
}
EXPORT_SYMBOL_GPL(devm_create_dax_dev);
/* return an unmapped area aligned to the dax region specified alignment */
static unsigned long dax_dev_get_unmapped_area(struct file *filp,
unsigned long addr, unsigned long len, unsigned long pgoff,
unsigned long flags)
{
unsigned long off, off_end, off_align, len_align, addr_align, align;
struct dax_dev *dax_dev = filp ? filp->private_data : NULL;
struct dax_region *dax_region;
if (!dax_dev || addr)
goto out;
dax_region = dax_dev->region;
align = dax_region->align;
off = pgoff << PAGE_SHIFT;
off_end = off + len;
off_align = round_up(off, align);
if ((off_end <= off_align) || ((off_end - off_align) < align))
goto out;
len_align = len + align;
if ((off + len_align) < off)
goto out;
addr_align = current->mm->get_unmapped_area(filp, addr, len_align,
pgoff, flags);
if (!IS_ERR_VALUE(addr_align)) {
addr_align += (off - addr_align) & (align - 1);
return addr_align;
}
out:
return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
}
static int __match_devt(struct device *dev, const void *data)
{
const dev_t *devt = data;
return dev->devt == *devt;
}
static struct device *dax_dev_find(dev_t dev_t)
{
return class_find_device(dax_class, NULL, &dev_t, __match_devt);
}
static int dax_dev_open(struct inode *inode, struct file *filp)
{
struct dax_dev *dax_dev = NULL;
struct device *dev;
dev = dax_dev_find(inode->i_rdev);
if (!dev)
return -ENXIO;
device_lock(dev);
dax_dev = dev_get_drvdata(dev);
if (dax_dev) {
dev_dbg(dev, "%s\n", __func__);
filp->private_data = dax_dev;
kref_get(&dax_dev->kref);
inode->i_flags = S_DAX;
}
device_unlock(dev);
if (!dax_dev) {
put_device(dev);
return -ENXIO;
}
return 0;
}
static int dax_dev_release(struct inode *inode, struct file *filp)
{
struct dax_dev *dax_dev = filp->private_data;
struct device *dev = dax_dev->dev;
dev_dbg(dax_dev->dev, "%s\n", __func__);
dax_dev_put(dax_dev);
put_device(dev);
return 0;
}
static int check_vma(struct dax_dev *dax_dev, struct vm_area_struct *vma,
const char *func)
{
struct dax_region *dax_region = dax_dev->region;
struct device *dev = dax_dev->dev;
struct device *dev = &dax_dev->dev;
unsigned long mask;
if (!dax_dev->alive)
@ -382,7 +329,7 @@ static int __dax_dev_fault(struct dax_dev *dax_dev, struct vm_area_struct *vma,
struct vm_fault *vmf)
{
unsigned long vaddr = (unsigned long) vmf->virtual_address;
struct device *dev = dax_dev->dev;
struct device *dev = &dax_dev->dev;
struct dax_region *dax_region;
int rc = VM_FAULT_SIGBUS;
phys_addr_t phys;
@ -422,7 +369,7 @@ static int dax_dev_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
struct file *filp = vma->vm_file;
struct dax_dev *dax_dev = filp->private_data;
dev_dbg(dax_dev->dev, "%s: %s: %s (%#lx - %#lx)\n", __func__,
dev_dbg(&dax_dev->dev, "%s: %s: %s (%#lx - %#lx)\n", __func__,
current->comm, (vmf->flags & FAULT_FLAG_WRITE)
? "write" : "read", vma->vm_start, vma->vm_end);
rcu_read_lock();
@ -437,7 +384,7 @@ static int __dax_dev_pmd_fault(struct dax_dev *dax_dev,
unsigned int flags)
{
unsigned long pmd_addr = addr & PMD_MASK;
struct device *dev = dax_dev->dev;
struct device *dev = &dax_dev->dev;
struct dax_region *dax_region;
phys_addr_t phys;
pgoff_t pgoff;
@ -479,7 +426,7 @@ static int dax_dev_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
struct file *filp = vma->vm_file;
struct dax_dev *dax_dev = filp->private_data;
dev_dbg(dax_dev->dev, "%s: %s: %s (%#lx - %#lx)\n", __func__,
dev_dbg(&dax_dev->dev, "%s: %s: %s (%#lx - %#lx)\n", __func__,
current->comm, (flags & FAULT_FLAG_WRITE)
? "write" : "read", vma->vm_start, vma->vm_end);
@ -490,81 +437,257 @@ static int dax_dev_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
return rc;
}
static void dax_dev_vm_open(struct vm_area_struct *vma)
{
struct file *filp = vma->vm_file;
struct dax_dev *dax_dev = filp->private_data;
dev_dbg(dax_dev->dev, "%s\n", __func__);
kref_get(&dax_dev->kref);
}
static void dax_dev_vm_close(struct vm_area_struct *vma)
{
struct file *filp = vma->vm_file;
struct dax_dev *dax_dev = filp->private_data;
dev_dbg(dax_dev->dev, "%s\n", __func__);
dax_dev_put(dax_dev);
}
static const struct vm_operations_struct dax_dev_vm_ops = {
.fault = dax_dev_fault,
.pmd_fault = dax_dev_pmd_fault,
.open = dax_dev_vm_open,
.close = dax_dev_vm_close,
};
static int dax_dev_mmap(struct file *filp, struct vm_area_struct *vma)
static int dax_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct dax_dev *dax_dev = filp->private_data;
int rc;
dev_dbg(dax_dev->dev, "%s\n", __func__);
dev_dbg(&dax_dev->dev, "%s\n", __func__);
rc = check_vma(dax_dev, vma, __func__);
if (rc)
return rc;
kref_get(&dax_dev->kref);
vma->vm_ops = &dax_dev_vm_ops;
vma->vm_flags |= VM_MIXEDMAP | VM_HUGEPAGE;
return 0;
}
/* return an unmapped area aligned to the dax region specified alignment */
static unsigned long dax_get_unmapped_area(struct file *filp,
unsigned long addr, unsigned long len, unsigned long pgoff,
unsigned long flags)
{
unsigned long off, off_end, off_align, len_align, addr_align, align;
struct dax_dev *dax_dev = filp ? filp->private_data : NULL;
struct dax_region *dax_region;
if (!dax_dev || addr)
goto out;
dax_region = dax_dev->region;
align = dax_region->align;
off = pgoff << PAGE_SHIFT;
off_end = off + len;
off_align = round_up(off, align);
if ((off_end <= off_align) || ((off_end - off_align) < align))
goto out;
len_align = len + align;
if ((off + len_align) < off)
goto out;
addr_align = current->mm->get_unmapped_area(filp, addr, len_align,
pgoff, flags);
if (!IS_ERR_VALUE(addr_align)) {
addr_align += (off - addr_align) & (align - 1);
return addr_align;
}
out:
return current->mm->get_unmapped_area(filp, addr, len, pgoff, flags);
}
static int dax_open(struct inode *inode, struct file *filp)
{
struct dax_dev *dax_dev;
dax_dev = container_of(inode->i_cdev, struct dax_dev, cdev);
dev_dbg(&dax_dev->dev, "%s\n", __func__);
inode->i_mapping = dax_dev->inode->i_mapping;
inode->i_mapping->host = dax_dev->inode;
filp->f_mapping = inode->i_mapping;
filp->private_data = dax_dev;
inode->i_flags = S_DAX;
return 0;
}
static int dax_release(struct inode *inode, struct file *filp)
{
struct dax_dev *dax_dev = filp->private_data;
dev_dbg(&dax_dev->dev, "%s\n", __func__);
return 0;
}
static const struct file_operations dax_fops = {
.llseek = noop_llseek,
.owner = THIS_MODULE,
.open = dax_dev_open,
.release = dax_dev_release,
.get_unmapped_area = dax_dev_get_unmapped_area,
.mmap = dax_dev_mmap,
.open = dax_open,
.release = dax_release,
.get_unmapped_area = dax_get_unmapped_area,
.mmap = dax_mmap,
};
static void dax_dev_release(struct device *dev)
{
struct dax_dev *dax_dev = to_dax_dev(dev);
struct dax_region *dax_region = dax_dev->region;
ida_simple_remove(&dax_region->ida, dax_dev->id);
ida_simple_remove(&dax_minor_ida, MINOR(dev->devt));
dax_region_put(dax_region);
iput(dax_dev->inode);
kfree(dax_dev);
}
static void unregister_dax_dev(void *dev)
{
struct dax_dev *dax_dev = to_dax_dev(dev);
struct cdev *cdev = &dax_dev->cdev;
dev_dbg(dev, "%s\n", __func__);
/*
* Note, rcu is not protecting the liveness of dax_dev, rcu is
* ensuring that any fault handlers that might have seen
* dax_dev->alive == true, have completed. Any fault handlers
* that start after synchronize_rcu() has started will abort
* upon seeing dax_dev->alive == false.
*/
dax_dev->alive = false;
synchronize_rcu();
unmap_mapping_range(dax_dev->inode->i_mapping, 0, 0, 1);
cdev_del(cdev);
device_unregister(dev);
}
struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
struct resource *res, int count)
{
struct device *parent = dax_region->dev;
struct dax_dev *dax_dev;
int rc = 0, minor, i;
struct device *dev;
struct cdev *cdev;
dev_t dev_t;
dax_dev = kzalloc(sizeof(*dax_dev) + sizeof(*res) * count, GFP_KERNEL);
if (!dax_dev)
return ERR_PTR(-ENOMEM);
for (i = 0; i < count; i++) {
if (!IS_ALIGNED(res[i].start, dax_region->align)
|| !IS_ALIGNED(resource_size(&res[i]),
dax_region->align)) {
rc = -EINVAL;
break;
}
dax_dev->res[i].start = res[i].start;
dax_dev->res[i].end = res[i].end;
}
if (i < count)
goto err_id;
dax_dev->id = ida_simple_get(&dax_region->ida, 0, 0, GFP_KERNEL);
if (dax_dev->id < 0) {
rc = dax_dev->id;
goto err_id;
}
minor = ida_simple_get(&dax_minor_ida, 0, 0, GFP_KERNEL);
if (minor < 0) {
rc = minor;
goto err_minor;
}
dev_t = MKDEV(MAJOR(dax_devt), minor);
dev = &dax_dev->dev;
dax_dev->inode = dax_inode_get(&dax_dev->cdev, dev_t);
if (!dax_dev->inode) {
rc = -ENOMEM;
goto err_inode;
}
/* device_initialize() so cdev can reference kobj parent */
device_initialize(dev);
cdev = &dax_dev->cdev;
cdev_init(cdev, &dax_fops);
cdev->owner = parent->driver->owner;
cdev->kobj.parent = &dev->kobj;
rc = cdev_add(&dax_dev->cdev, dev_t, 1);
if (rc)
goto err_cdev;
/* from here on we're committed to teardown via dax_dev_release() */
dax_dev->num_resources = count;
dax_dev->alive = true;
dax_dev->region = dax_region;
kref_get(&dax_region->kref);
dev->devt = dev_t;
dev->class = dax_class;
dev->parent = parent;
dev->groups = dax_attribute_groups;
dev->release = dax_dev_release;
dev_set_name(dev, "dax%d.%d", dax_region->id, dax_dev->id);
rc = device_add(dev);
if (rc) {
put_device(dev);
return ERR_PTR(rc);
}
rc = devm_add_action_or_reset(dax_region->dev, unregister_dax_dev, dev);
if (rc)
return ERR_PTR(rc);
return dax_dev;
err_cdev:
iput(dax_dev->inode);
err_inode:
ida_simple_remove(&dax_minor_ida, minor);
err_minor:
ida_simple_remove(&dax_region->ida, dax_dev->id);
err_id:
kfree(dax_dev);
return ERR_PTR(rc);
}
EXPORT_SYMBOL_GPL(devm_create_dax_dev);
static int __init dax_init(void)
{
int rc;
rc = register_chrdev(0, "dax", &dax_fops);
if (rc < 0)
rc = dax_inode_init();
if (rc)
return rc;
dax_major = rc;
nr_dax = max(nr_dax, 256);
rc = alloc_chrdev_region(&dax_devt, 0, nr_dax, "dax");
if (rc)
goto err_chrdev;
dax_class = class_create(THIS_MODULE, "dax");
if (IS_ERR(dax_class)) {
unregister_chrdev(dax_major, "dax");
return PTR_ERR(dax_class);
rc = PTR_ERR(dax_class);
goto err_class;
}
return 0;
err_class:
unregister_chrdev_region(dax_devt, nr_dax);
err_chrdev:
dax_inode_exit();
return rc;
}
static void __exit dax_exit(void)
{
class_destroy(dax_class);
unregister_chrdev(dax_major, "dax");
unregister_chrdev_region(dax_devt, nr_dax);
ida_destroy(&dax_minor_ida);
dax_inode_exit();
}
MODULE_AUTHOR("Intel Corporation");

Просмотреть файл

@ -13,12 +13,13 @@
#ifndef __DAX_H__
#define __DAX_H__
struct device;
struct dax_dev;
struct resource;
struct dax_region;
void dax_region_put(struct dax_region *dax_region);
struct dax_region *alloc_dax_region(struct device *parent,
int region_id, struct resource *res, unsigned int align,
void *addr, unsigned long flags);
int devm_create_dax_dev(struct dax_region *dax_region, struct resource *res,
int count);
struct dax_dev *devm_create_dax_dev(struct dax_region *dax_region,
struct resource *res, int count);
#endif /* __DAX_H__ */

Просмотреть файл

@ -24,7 +24,7 @@ struct dax_pmem {
struct completion cmp;
};
struct dax_pmem *to_dax_pmem(struct percpu_ref *ref)
static struct dax_pmem *to_dax_pmem(struct percpu_ref *ref)
{
return container_of(ref, struct dax_pmem, ref);
}
@ -61,6 +61,7 @@ static int dax_pmem_probe(struct device *dev)
int rc;
void *addr;
struct resource res;
struct dax_dev *dax_dev;
struct nd_pfn_sb *pfn_sb;
struct dax_pmem *dax_pmem;
struct nd_region *nd_region;
@ -126,12 +127,12 @@ static int dax_pmem_probe(struct device *dev)
return -ENOMEM;
/* TODO: support for subdividing a dax region... */
rc = devm_create_dax_dev(dax_region, &res, 1);
dax_dev = devm_create_dax_dev(dax_region, &res, 1);
/* child dax_dev instances now own the lifetime of the dax_region */
dax_region_put(dax_region);
return rc;
return PTR_ERR_OR_ZERO(dax_dev);
}
static struct nd_device_driver dax_pmem_driver = {

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@ -89,7 +89,7 @@ config NVDIMM_PFN
Select Y if unsure
config NVDIMM_DAX
bool "NVDIMM DAX: Raw access to persistent memory"
tristate "NVDIMM DAX: Raw access to persistent memory"
default LIBNVDIMM
depends on NVDIMM_PFN
help

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@ -406,6 +406,7 @@ void cd_forget(struct inode *inode)
spin_lock(&cdev_lock);
list_del_init(&inode->i_devices);
inode->i_cdev = NULL;
inode->i_mapping = &inode->i_data;
spin_unlock(&cdev_lock);
}

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@ -65,6 +65,7 @@
#define V9FS_MAGIC 0x01021997
#define BDEVFS_MAGIC 0x62646576
#define DAXFS_MAGIC 0x64646178
#define BINFMTFS_MAGIC 0x42494e4d
#define DEVPTS_SUPER_MAGIC 0x1cd1
#define FUTEXFS_SUPER_MAGIC 0xBAD1DEA