| /* |
| FUSE: Filesystem in Userspace |
| Copyright (C) 2001 Miklos Szeredi (mszeredi@inf.bme.hu) |
| |
| This program can be distributed under the terms of the GNU GPL. |
| See the file COPYING. |
| */ |
| |
| #include "fuse_i.h" |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| #include <linux/file.h> |
| |
| #define FUSE_SUPER_MAGIC 0x65735546 |
| |
| static void fuse_read_inode(struct inode *inode) |
| { |
| /* No op */ |
| } |
| |
| static void send_forget(struct fuse_conn *fc, unsigned long *forget, |
| unsigned int numforget) |
| { |
| struct fuse_in in = FUSE_IN_INIT; |
| |
| in.h.opcode = FUSE_FORGET; |
| in.h.ino = 0; |
| in.argsize = numforget * sizeof(unsigned long); |
| in.arg = forget; |
| |
| request_send(fc, &in, NULL); |
| } |
| |
| static int alloc_cleared(struct fuse_conn *fc) |
| { |
| unsigned long *tmp; |
| |
| spin_unlock(&fuse_lock); |
| tmp = kmalloc(sizeof(unsigned long) * MAX_CLEARED, GFP_NOFS); |
| spin_lock(&fuse_lock); |
| |
| if(!fc->file || fc->cleared != NULL) |
| kfree(tmp); |
| else if(!tmp) |
| printk("fuse_clear_inode: Cannot allocate memory\n"); |
| else |
| fc->cleared = tmp; |
| |
| return fc->cleared != NULL; |
| } |
| |
| static unsigned long *add_cleared(struct fuse_conn *fc, unsigned long ino) |
| { |
| if(!fc->file || (!fc->cleared && !alloc_cleared(fc))) |
| return NULL; |
| |
| fc->cleared[fc->numcleared] = ino; |
| fc->numcleared ++; |
| |
| if(fc->numcleared == MAX_CLEARED) { |
| unsigned long *tmp = fc->cleared; |
| fc->cleared = NULL; |
| fc->numcleared = 0; |
| return tmp; |
| } |
| |
| return NULL; |
| } |
| |
| static void fuse_clear_inode(struct inode *inode) |
| { |
| struct fuse_conn *fc = INO_FC(inode); |
| unsigned long *forget; |
| |
| spin_lock(&fuse_lock); |
| forget = add_cleared(fc, inode->i_ino); |
| spin_unlock(&fuse_lock); |
| |
| if(forget) { |
| send_forget(fc, forget, MAX_CLEARED); |
| kfree(forget); |
| } |
| } |
| |
| static void fuse_put_super(struct super_block *sb) |
| { |
| struct fuse_conn *fc = sb->u.generic_sbp; |
| |
| spin_lock(&fuse_lock); |
| fc->sb = NULL; |
| fuse_release_conn(fc); |
| spin_unlock(&fuse_lock); |
| |
| } |
| |
| static struct super_operations fuse_super_operations = { |
| read_inode: fuse_read_inode, |
| clear_inode: fuse_clear_inode, |
| put_super: fuse_put_super, |
| }; |
| |
| |
| static struct fuse_conn *get_conn(struct fuse_mount_data *d) |
| { |
| struct fuse_conn *fc = NULL; |
| struct file *file; |
| struct inode *ino; |
| |
| if(d == NULL) { |
| printk("fuse_read_super: Bad mount data\n"); |
| return NULL; |
| } |
| |
| if(d->version != FUSE_MOUNT_VERSION) { |
| printk("fuse_read_super: Bad mount version: %i\n", d->version); |
| return NULL; |
| } |
| |
| file = fget(d->fd); |
| ino = NULL; |
| if(file) |
| ino = file->f_dentry->d_inode; |
| |
| if(!ino || ino->u.generic_ip != proc_fuse_dev) { |
| printk("fuse_read_super: Bad file: %i\n", d->fd); |
| goto out; |
| } |
| |
| fc = file->private_data; |
| |
| out: |
| fput(file); |
| return fc; |
| |
| } |
| |
| static struct inode *get_root_inode(struct super_block *sb) |
| { |
| struct fuse_attr attr; |
| memset(&attr, 0, sizeof(attr)); |
| |
| attr.mode = S_IFDIR; |
| return fuse_iget(sb, 1, &attr); |
| } |
| |
| static struct super_block *fuse_read_super(struct super_block *sb, |
| void *data, int silent) |
| { |
| struct fuse_conn *fc; |
| struct inode *root; |
| |
| sb->s_blocksize = 1024; |
| sb->s_blocksize_bits = 10; |
| sb->s_magic = FUSE_SUPER_MAGIC; |
| sb->s_op = &fuse_super_operations; |
| |
| root = get_root_inode(sb); |
| if(root == NULL) { |
| printk("fuse_read_super: failed to get root inode\n"); |
| return NULL; |
| } |
| |
| spin_lock(&fuse_lock); |
| fc = get_conn(data); |
| if(fc == NULL) |
| goto err; |
| |
| if(fc->sb != NULL) { |
| printk("fuse_read_super: connection %i already mounted\n", |
| fc->id); |
| goto err; |
| } |
| |
| sb->u.generic_sbp = fc; |
| sb->s_root = d_alloc_root(root); |
| if(!sb->s_root) |
| goto err; |
| |
| fc->sb = sb; |
| spin_unlock(&fuse_lock); |
| |
| return sb; |
| |
| err: |
| spin_unlock(&fuse_lock); |
| iput(root); |
| return NULL; |
| } |
| |
| |
| static DECLARE_FSTYPE(fuse_fs_type, "fuse", fuse_read_super, 0); |
| |
| int fuse_fs_init() |
| { |
| int res; |
| |
| res = register_filesystem(&fuse_fs_type); |
| if(res) |
| printk("fuse: failed to register filesystem\n"); |
| |
| return res; |
| } |
| |
| void fuse_fs_cleanup() |
| { |
| unregister_filesystem(&fuse_fs_type); |
| } |
| |
| /* |
| * Local Variables: |
| * indent-tabs-mode: t |
| * c-basic-offset: 8 |
| * End: |
| */ |
| |