From d6d281684913dabb878e2f53219eed5df2cd867b Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 28 Jun 2007 08:38:16 -0400 Subject: [PATCH] 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 Signed-off-by: Avi Kivity --- drivers/kvm/kvm_main.c | 143 ++++------------------------------------- fs/anon_inodes.c | 1 + include/linux/magic.h | 1 - 3 files changed, 12 insertions(+), 133 deletions(-) diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index 5603000573e..26ca90f74fc 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -43,6 +43,7 @@ #include #include #include +#include #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(); } diff --git a/fs/anon_inodes.c b/fs/anon_inodes.c index 40fe3a3222e..edc67486238 100644 --- a/fs/anon_inodes.c +++ b/fs/anon_inodes.c @@ -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, diff --git a/include/linux/magic.h b/include/linux/magic.h index 9d713c03e3d..36cc20dfd14 100644 --- a/include/linux/magic.h +++ b/include/linux/magic.h @@ -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 */