KVM: Remove kvmfs in favor of the anonymous inodes source

kvm uses a pseudo filesystem, kvmfs, to generate inodes, a job that the
new anonymous inodes source does much better.

Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity 2007-06-28 08:38:16 -04:00
parent 6031a61c2e
commit d6d2816849
3 changed files with 12 additions and 133 deletions

View file

@ -43,6 +43,7 @@
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/smp.h>
#include <linux/anon_inodes.h>
#include "x86_emulate.h"
#include "segment_descriptor.h"
@ -81,8 +82,6 @@ static struct kvm_stats_debugfs_item {
static struct dentry *debugfs_dir;
struct vfsmount *kvmfs_mnt;
#define MAX_IO_MSRS 256
#define CR0_RESEVED_BITS 0xffffffff1ffaffc0ULL
@ -104,55 +103,6 @@ struct segment_descriptor_64 {
static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
unsigned long arg);
static struct inode *kvmfs_inode(struct file_operations *fops)
{
int error = -ENOMEM;
struct inode *inode = new_inode(kvmfs_mnt->mnt_sb);
if (!inode)
goto eexit_1;
inode->i_fop = fops;
/*
* Mark the inode dirty from the very beginning,
* that way it will never be moved to the dirty
* list because mark_inode_dirty() will think
* that it already _is_ on the dirty list.
*/
inode->i_state = I_DIRTY;
inode->i_mode = S_IRUSR | S_IWUSR;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
return inode;
eexit_1:
return ERR_PTR(error);
}
static struct file *kvmfs_file(struct inode *inode, void *private_data)
{
struct file *file = get_empty_filp();
if (!file)
return ERR_PTR(-ENFILE);
file->f_path.mnt = mntget(kvmfs_mnt);
file->f_path.dentry = d_alloc_anon(inode);
if (!file->f_path.dentry)
return ERR_PTR(-ENOMEM);
file->f_mapping = inode->i_mapping;
file->f_pos = 0;
file->f_flags = O_RDWR;
file->f_op = inode->i_fop;
file->f_mode = FMODE_READ | FMODE_WRITE;
file->f_version = 0;
file->private_data = private_data;
return file;
}
unsigned long segment_base(u16 selector)
{
struct descriptor_table gdt;
@ -2413,34 +2363,12 @@ static int create_vcpu_fd(struct kvm_vcpu *vcpu)
struct inode *inode;
struct file *file;
r = anon_inode_getfd(&fd, &inode, &file,
"kvm-vcpu", &kvm_vcpu_fops, vcpu);
if (r)
return r;
atomic_inc(&vcpu->kvm->filp->f_count);
inode = kvmfs_inode(&kvm_vcpu_fops);
if (IS_ERR(inode)) {
r = PTR_ERR(inode);
goto out1;
}
file = kvmfs_file(inode, vcpu);
if (IS_ERR(file)) {
r = PTR_ERR(file);
goto out2;
}
r = get_unused_fd();
if (r < 0)
goto out3;
fd = r;
fd_install(fd, file);
return fd;
out3:
fput(file);
out2:
iput(inode);
out1:
fput(vcpu->kvm->filp);
return r;
}
/*
@ -2905,41 +2833,18 @@ static int kvm_dev_ioctl_create_vm(void)
struct file *file;
struct kvm *kvm;
inode = kvmfs_inode(&kvm_vm_fops);
if (IS_ERR(inode)) {
r = PTR_ERR(inode);
goto out1;
}
kvm = kvm_create_vm();
if (IS_ERR(kvm)) {
r = PTR_ERR(kvm);
goto out2;
if (IS_ERR(kvm))
return PTR_ERR(kvm);
r = anon_inode_getfd(&fd, &inode, &file, "kvm-vm", &kvm_vm_fops, kvm);
if (r) {
kvm_destroy_vm(kvm);
return r;
}
file = kvmfs_file(inode, kvm);
if (IS_ERR(file)) {
r = PTR_ERR(file);
goto out3;
}
kvm->filp = file;
r = get_unused_fd();
if (r < 0)
goto out4;
fd = r;
fd_install(fd, file);
return fd;
out4:
fput(file);
out3:
kvm_destroy_vm(kvm);
out2:
iput(inode);
out1:
return r;
}
static long kvm_dev_ioctl(struct file *filp,
@ -3211,18 +3116,6 @@ static struct sys_device kvm_sysdev = {
hpa_t bad_page_address;
static int kvmfs_get_sb(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data, struct vfsmount *mnt)
{
return get_sb_pseudo(fs_type, "kvm:", NULL, KVMFS_SUPER_MAGIC, mnt);
}
static struct file_system_type kvm_fs_type = {
.name = "kvmfs",
.get_sb = kvmfs_get_sb,
.kill_sb = kill_anon_super,
};
int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module)
{
int r;
@ -3307,14 +3200,6 @@ static __init int kvm_init(void)
if (r)
goto out4;
r = register_filesystem(&kvm_fs_type);
if (r)
goto out3;
kvmfs_mnt = kern_mount(&kvm_fs_type);
r = PTR_ERR(kvmfs_mnt);
if (IS_ERR(kvmfs_mnt))
goto out2;
kvm_init_debug();
kvm_init_msr_list();
@ -3331,10 +3216,6 @@ static __init int kvm_init(void)
out:
kvm_exit_debug();
mntput(kvmfs_mnt);
out2:
unregister_filesystem(&kvm_fs_type);
out3:
kvm_mmu_module_exit();
out4:
return r;
@ -3344,8 +3225,6 @@ static __exit void kvm_exit(void)
{
kvm_exit_debug();
__free_page(pfn_to_page(bad_page_address >> PAGE_SHIFT));
mntput(kvmfs_mnt);
unregister_filesystem(&kvm_fs_type);
kvm_mmu_module_exit();
}

View file

@ -139,6 +139,7 @@ err_put_filp:
put_filp(file);
return error;
}
EXPORT_SYMBOL_GPL(anon_inode_getfd);
/*
* A single inode exist for all anon_inode files. Contrary to pipes,

View file

@ -13,7 +13,6 @@
#define HPFS_SUPER_MAGIC 0xf995e849
#define ISOFS_SUPER_MAGIC 0x9660
#define JFFS2_SUPER_MAGIC 0x72b6
#define KVMFS_SUPER_MAGIC 0x19700426
#define ANON_INODE_FS_MAGIC 0x09041934
#define MINIX_SUPER_MAGIC 0x137F /* original minix fs */