diff options
Diffstat (limited to 'kernel/dir.c')
| -rw-r--r-- | kernel/dir.c | 384 |
1 files changed, 384 insertions, 0 deletions
diff --git a/kernel/dir.c b/kernel/dir.c new file mode 100644 index 0000000..92ddc55 --- /dev/null +++ b/kernel/dir.c @@ -0,0 +1,384 @@ +/* + 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/file.h> +#include <linux/slab.h> + +static void change_attributes(struct inode *inode, struct fuse_attr *attr) +{ + inode->i_mode = attr->mode; + inode->i_nlink = attr->nlink; + inode->i_uid = attr->uid; + inode->i_gid = attr->gid; + inode->i_size = attr->size; + inode->i_blksize = attr->blksize; + inode->i_blocks = attr->blocks; + inode->i_atime = attr->atime; + inode->i_mtime = attr->mtime; + inode->i_ctime = attr->ctime; +} + +static void init_inode(struct inode *inode, struct fuse_attr *attr) +{ + change_attributes(inode, attr); + + if(S_ISREG(inode->i_mode)) + fuse_file_init(inode); + else if(S_ISDIR(inode->i_mode)) + fuse_dir_init(inode); + else if(S_ISLNK(inode->i_mode)) + fuse_symlink_init(inode); + else { + fuse_special_init(inode); + init_special_inode(inode, inode->i_mode, attr->rdev); + } +} + + +static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry) +{ + struct fuse_conn *fc = dir->i_sb->u.generic_sbp; + struct fuse_in in = FUSE_IN_INIT; + struct fuse_out out = FUSE_OUT_INIT; + struct fuse_lookup_out arg; + struct inode *inode; + + in.h.opcode = FUSE_LOOKUP; + in.h.ino = dir->i_ino; + in.argsize = entry->d_name.len + 1; + in.arg = entry->d_name.name; + out.argsize = sizeof(arg); + out.arg = &arg; + request_send(fc, &in, &out); + + if(out.h.result) { + /* Negative dentries are not hashed */ + if(out.h.result == -ENOENT) + return NULL; + else + return ERR_PTR(out.h.result); + } + + inode = iget(dir->i_sb, arg.ino); + if(!inode) + return ERR_PTR(-ENOMEM); + + init_inode(inode, &arg.attr); + d_add(entry, inode); + return NULL; +} + +static int fuse_mknod(struct inode *dir, struct dentry *entry, int mode, + int rdev) +{ + struct fuse_conn *fc = dir->i_sb->u.generic_sbp; + struct fuse_in in = FUSE_IN_INIT; + struct fuse_out out = FUSE_OUT_INIT; + struct fuse_mknod_in *inarg; + unsigned int insize; + struct fuse_mknod_out outarg; + struct inode *inode; + + insize = offsetof(struct fuse_mknod_in, name) + entry->d_name.len + 1; + inarg = kmalloc(insize, GFP_KERNEL); + if(!inarg) + return -ENOMEM; + + inarg->mode = mode; + inarg->rdev = rdev; + strcpy(inarg->name, entry->d_name.name); + + in.h.opcode = FUSE_MKNOD; + in.h.ino = dir->i_ino; + in.argsize = insize; + in.arg = inarg; + out.argsize = sizeof(outarg); + out.arg = &outarg; + request_send(fc, &in, &out); + kfree(inarg); + if(out.h.result) + return out.h.result; + + inode = iget(dir->i_sb, outarg.ino); + if(!inode) + return -ENOMEM; + + init_inode(inode, &outarg.attr); + d_add(entry, inode); + return 0; +} + +static int fuse_create(struct inode *dir, struct dentry *entry, int mode) +{ + return fuse_mknod(dir, entry, mode, 0); +} + +static int fuse_permission(struct inode *inode, int mask) +{ + + return 0; +} + +static int fuse_revalidate(struct dentry *dentry) +{ + struct inode *inode = dentry->d_inode; + struct fuse_conn *fc = inode->i_sb->u.generic_sbp; + struct fuse_in in = FUSE_IN_INIT; + struct fuse_out out = FUSE_OUT_INIT; + struct fuse_getattr_out arg; + + in.h.opcode = FUSE_GETATTR; + in.h.ino = inode->i_ino; + out.argsize = sizeof(arg); + out.arg = &arg; + request_send(fc, &in, &out); + + if(out.h.result == 0) + change_attributes(inode, &arg.attr); + + return out.h.result; +} + + +#define DIR_BUFSIZE 2048 + +static int fuse_readdir(struct file *file, void *dstbuf, filldir_t filldir) +{ + struct file *cfile = file->private_data; + char *buf; + char *p; + int ret; + size_t nbytes; + + buf = kmalloc(DIR_BUFSIZE, GFP_KERNEL); + if(!buf) + return -ENOMEM; + + ret = kernel_read(cfile, file->f_pos, buf, DIR_BUFSIZE); + if(ret < 0) { + printk("fuse_readdir: failed to read container file\n"); + goto out; + } + nbytes = ret; + p = buf; + ret = 0; + while(nbytes >= FUSE_NAME_OFFSET) { + struct fuse_dirent *dirent = (struct fuse_dirent *) p; + size_t reclen = FUSE_DIRENT_SIZE(dirent); + int over; + if(dirent->namelen > NAME_MAX) { + printk("fuse_readdir: name too long\n"); + ret = -EPROTO; + goto out; + } + if(reclen > nbytes) + break; + + over = filldir(dstbuf, dirent->name, dirent->namelen, + file->f_pos, dirent->ino, dirent->type); + if(over) + break; + + p += reclen; + file->f_pos += reclen; + nbytes -= reclen; + } + + out: + kfree(buf); + return ret; +} + + + +static int read_link(struct dentry *dentry, char **bufp) +{ + struct inode *inode = dentry->d_inode; + struct fuse_conn *fc = inode->i_sb->u.generic_sbp; + struct fuse_in in = FUSE_IN_INIT; + struct fuse_out out = FUSE_OUT_INIT; + unsigned long page; + + page = __get_free_page(GFP_KERNEL); + if(!page) + return -ENOMEM; + + in.h.opcode = FUSE_READLINK; + in.h.ino = inode->i_ino; + out.arg = (void *) page; + out.argsize = PAGE_SIZE - 1; + out.argvar = 1; + request_send(fc, &in, &out); + if(out.h.result) { + free_page(page); + return out.h.result; + } + + *bufp = (char *) page; + (*bufp)[out.argsize] = '\0'; + return 0; +} + +static void free_link(char *link) +{ + free_page((unsigned long) link); +} + +static int fuse_readlink(struct dentry *dentry, char *buffer, int buflen) +{ + int ret; + char *link; + + ret = read_link(dentry, &link); + if(ret) + return ret; + + ret = vfs_readlink(dentry, buffer, buflen, link); + free_link(link); + return ret; +} + +static int fuse_follow_link(struct dentry *dentry, struct nameidata *nd) +{ + int ret; + char *link; + + ret = read_link(dentry, &link); + if(ret) + return ret; + + ret = vfs_follow_link(nd, link); + free_link(link); + return ret; +} + +static int fuse_dir_open(struct inode *inode, struct file *file) +{ + struct fuse_conn *fc = inode->i_sb->u.generic_sbp; + struct fuse_in in = FUSE_IN_INIT; + struct fuse_out out = FUSE_OUT_INIT; + struct fuse_getdir_out outarg; + + if(!(file->f_flags & O_DIRECTORY)) + return -EISDIR; + + in.h.opcode = FUSE_GETDIR; + in.h.ino = inode->i_ino; + out.argsize = sizeof(outarg); + out.arg = &outarg; + request_send(fc, &in, &out); + if(out.h.result == 0) { + struct file *cfile = outarg.file; + struct inode *inode; + if(!cfile) { + printk("fuse_getdir: invalid file\n"); + return -EPROTO; + } + inode = cfile->f_dentry->d_inode; + if(!S_ISREG(inode->i_mode)) { + printk("fuse_getdir: not a regular file\n"); + fput(cfile); + return -EPROTO; + } + + file->private_data = cfile; + } + + return out.h.result; +} + +static int fuse_dir_release(struct inode *inode, struct file *file) +{ + struct file *cfile = file->private_data; + + if(!cfile) + BUG(); + + fput(cfile); + + return 0; +} + +static struct inode_operations fuse_dir_inode_operations = +{ + lookup: fuse_lookup, + create: fuse_create, + mknod: fuse_mknod, +#if 0 + + link: fuse_link, + unlink: fuse_unlink, + symlink: fuse_symlink, + mkdir: fuse_mkdir, + rmdir: fuse_rmdir, + rename: fuse_rename, +#endif + permission: fuse_permission, + revalidate: fuse_revalidate, +}; + +static struct file_operations fuse_dir_operations = { + read: generic_read_dir, + readdir: fuse_readdir, + open: fuse_dir_open, + release: fuse_dir_release, +}; + +static struct inode_operations fuse_file_inode_operations = { + permission: fuse_permission, + revalidate: fuse_revalidate, +}; + +static struct inode_operations fuse_special_inode_operations = { + permission: fuse_permission, + revalidate: fuse_revalidate, +}; + +static struct file_operations fuse_file_operations = { +}; + +static struct inode_operations fuse_symlink_inode_operations = +{ + readlink: fuse_readlink, + follow_link: fuse_follow_link, + revalidate: fuse_revalidate, +}; + +void fuse_dir_init(struct inode *inode) +{ + inode->i_op = &fuse_dir_inode_operations; + inode->i_fop = &fuse_dir_operations; +} + +void fuse_file_init(struct inode *inode) +{ + inode->i_op = &fuse_file_inode_operations; + inode->i_fop = &fuse_file_operations; +} + +void fuse_symlink_init(struct inode *inode) +{ + inode->i_op = &fuse_symlink_inode_operations; +} + +void fuse_special_init(struct inode *inode) +{ + inode->i_op = &fuse_special_inode_operations; +} + +/* + * Local Variables: + * indent-tabs-mode: t + * c-basic-offset: 8 + * End: + */ |