d12def1bcb
Libfuse basically creates a new thread for each new request. This is fine for synchronous requests, which are naturally limited. However background requests (especially writepage) can cause a thread creation storm. To avoid this, limit the number of background requests available to userspace. This is done by introducing another queue for background requests, and a counter for the number of "active" requests, which are currently available for userspace. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
872 lines
19 KiB
C
872 lines
19 KiB
C
/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
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This program can be distributed under the terms of the GNU GPL.
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See the file COPYING.
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*/
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#include "fuse_i.h"
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#include <linux/pagemap.h>
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#include <linux/slab.h>
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#include <linux/file.h>
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#include <linux/seq_file.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/parser.h>
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#include <linux/statfs.h>
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#include <linux/random.h>
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#include <linux/sched.h>
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MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
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MODULE_DESCRIPTION("Filesystem in Userspace");
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MODULE_LICENSE("GPL");
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static struct kmem_cache *fuse_inode_cachep;
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struct list_head fuse_conn_list;
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DEFINE_MUTEX(fuse_mutex);
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#define FUSE_SUPER_MAGIC 0x65735546
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struct fuse_mount_data {
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int fd;
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unsigned rootmode;
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unsigned user_id;
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unsigned group_id;
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unsigned fd_present : 1;
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unsigned rootmode_present : 1;
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unsigned user_id_present : 1;
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unsigned group_id_present : 1;
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unsigned flags;
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unsigned max_read;
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unsigned blksize;
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};
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static struct inode *fuse_alloc_inode(struct super_block *sb)
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{
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struct inode *inode;
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struct fuse_inode *fi;
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inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
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if (!inode)
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return NULL;
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fi = get_fuse_inode(inode);
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fi->i_time = 0;
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fi->nodeid = 0;
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fi->nlookup = 0;
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fi->attr_version = 0;
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INIT_LIST_HEAD(&fi->write_files);
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fi->forget_req = fuse_request_alloc();
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if (!fi->forget_req) {
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kmem_cache_free(fuse_inode_cachep, inode);
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return NULL;
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}
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return inode;
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}
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static void fuse_destroy_inode(struct inode *inode)
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{
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struct fuse_inode *fi = get_fuse_inode(inode);
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BUG_ON(!list_empty(&fi->write_files));
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if (fi->forget_req)
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fuse_request_free(fi->forget_req);
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kmem_cache_free(fuse_inode_cachep, inode);
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}
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static void fuse_read_inode(struct inode *inode)
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{
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/* No op */
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}
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void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
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unsigned long nodeid, u64 nlookup)
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{
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struct fuse_forget_in *inarg = &req->misc.forget_in;
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inarg->nlookup = nlookup;
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req->in.h.opcode = FUSE_FORGET;
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req->in.h.nodeid = nodeid;
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req->in.numargs = 1;
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req->in.args[0].size = sizeof(struct fuse_forget_in);
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req->in.args[0].value = inarg;
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request_send_noreply(fc, req);
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}
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static void fuse_clear_inode(struct inode *inode)
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{
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if (inode->i_sb->s_flags & MS_ACTIVE) {
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_inode *fi = get_fuse_inode(inode);
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fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
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fi->forget_req = NULL;
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}
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}
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static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
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{
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if (*flags & MS_MANDLOCK)
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return -EINVAL;
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return 0;
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}
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static void fuse_truncate(struct address_space *mapping, loff_t offset)
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{
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/* See vmtruncate() */
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unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
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truncate_inode_pages(mapping, offset);
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unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
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}
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void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
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u64 attr_valid, u64 attr_version)
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{
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struct fuse_conn *fc = get_fuse_conn(inode);
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struct fuse_inode *fi = get_fuse_inode(inode);
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loff_t oldsize;
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spin_lock(&fc->lock);
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if (attr_version != 0 && fi->attr_version > attr_version) {
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spin_unlock(&fc->lock);
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return;
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}
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fi->attr_version = ++fc->attr_version;
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fi->i_time = attr_valid;
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inode->i_ino = attr->ino;
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inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
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inode->i_nlink = attr->nlink;
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inode->i_uid = attr->uid;
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inode->i_gid = attr->gid;
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inode->i_blocks = attr->blocks;
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inode->i_atime.tv_sec = attr->atime;
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inode->i_atime.tv_nsec = attr->atimensec;
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inode->i_mtime.tv_sec = attr->mtime;
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inode->i_mtime.tv_nsec = attr->mtimensec;
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inode->i_ctime.tv_sec = attr->ctime;
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inode->i_ctime.tv_nsec = attr->ctimensec;
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if (attr->blksize != 0)
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inode->i_blkbits = ilog2(attr->blksize);
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else
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inode->i_blkbits = inode->i_sb->s_blocksize_bits;
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/*
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* Don't set the sticky bit in i_mode, unless we want the VFS
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* to check permissions. This prevents failures due to the
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* check in may_delete().
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*/
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fi->orig_i_mode = inode->i_mode;
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if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
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inode->i_mode &= ~S_ISVTX;
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oldsize = inode->i_size;
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i_size_write(inode, attr->size);
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spin_unlock(&fc->lock);
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if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
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if (attr->size < oldsize)
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fuse_truncate(inode->i_mapping, attr->size);
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invalidate_inode_pages2(inode->i_mapping);
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}
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}
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static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
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{
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inode->i_mode = attr->mode & S_IFMT;
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inode->i_size = attr->size;
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if (S_ISREG(inode->i_mode)) {
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fuse_init_common(inode);
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fuse_init_file_inode(inode);
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} else if (S_ISDIR(inode->i_mode))
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fuse_init_dir(inode);
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else if (S_ISLNK(inode->i_mode))
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fuse_init_symlink(inode);
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else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
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S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
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fuse_init_common(inode);
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init_special_inode(inode, inode->i_mode,
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new_decode_dev(attr->rdev));
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} else
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BUG();
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}
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static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
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{
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unsigned long nodeid = *(unsigned long *) _nodeidp;
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if (get_node_id(inode) == nodeid)
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return 1;
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else
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return 0;
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}
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static int fuse_inode_set(struct inode *inode, void *_nodeidp)
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{
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unsigned long nodeid = *(unsigned long *) _nodeidp;
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get_fuse_inode(inode)->nodeid = nodeid;
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return 0;
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}
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struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
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int generation, struct fuse_attr *attr,
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u64 attr_valid, u64 attr_version)
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{
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struct inode *inode;
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struct fuse_inode *fi;
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struct fuse_conn *fc = get_fuse_conn_super(sb);
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retry:
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inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
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if (!inode)
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return NULL;
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if ((inode->i_state & I_NEW)) {
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inode->i_flags |= S_NOATIME|S_NOCMTIME;
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inode->i_generation = generation;
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inode->i_data.backing_dev_info = &fc->bdi;
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fuse_init_inode(inode, attr);
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unlock_new_inode(inode);
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} else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
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/* Inode has changed type, any I/O on the old should fail */
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make_bad_inode(inode);
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iput(inode);
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goto retry;
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}
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fi = get_fuse_inode(inode);
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spin_lock(&fc->lock);
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fi->nlookup ++;
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spin_unlock(&fc->lock);
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fuse_change_attributes(inode, attr, attr_valid, attr_version);
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return inode;
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}
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static void fuse_umount_begin(struct vfsmount *vfsmnt, int flags)
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{
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if (flags & MNT_FORCE)
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fuse_abort_conn(get_fuse_conn_super(vfsmnt->mnt_sb));
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}
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static void fuse_send_destroy(struct fuse_conn *fc)
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{
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struct fuse_req *req = fc->destroy_req;
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if (req && fc->conn_init) {
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fc->destroy_req = NULL;
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req->in.h.opcode = FUSE_DESTROY;
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req->force = 1;
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request_send(fc, req);
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fuse_put_request(fc, req);
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}
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}
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static void fuse_put_super(struct super_block *sb)
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{
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struct fuse_conn *fc = get_fuse_conn_super(sb);
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fuse_send_destroy(fc);
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spin_lock(&fc->lock);
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fc->connected = 0;
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fc->blocked = 0;
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spin_unlock(&fc->lock);
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/* Flush all readers on this fs */
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kill_fasync(&fc->fasync, SIGIO, POLL_IN);
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wake_up_all(&fc->waitq);
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wake_up_all(&fc->blocked_waitq);
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wake_up_all(&fc->reserved_req_waitq);
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mutex_lock(&fuse_mutex);
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list_del(&fc->entry);
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fuse_ctl_remove_conn(fc);
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mutex_unlock(&fuse_mutex);
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fuse_conn_put(fc);
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}
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static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
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{
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stbuf->f_type = FUSE_SUPER_MAGIC;
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stbuf->f_bsize = attr->bsize;
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stbuf->f_frsize = attr->frsize;
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stbuf->f_blocks = attr->blocks;
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stbuf->f_bfree = attr->bfree;
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stbuf->f_bavail = attr->bavail;
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stbuf->f_files = attr->files;
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stbuf->f_ffree = attr->ffree;
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stbuf->f_namelen = attr->namelen;
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/* fsid is left zero */
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}
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static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
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{
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struct super_block *sb = dentry->d_sb;
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struct fuse_conn *fc = get_fuse_conn_super(sb);
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struct fuse_req *req;
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struct fuse_statfs_out outarg;
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int err;
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if (!fuse_allow_task(fc, current)) {
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buf->f_type = FUSE_SUPER_MAGIC;
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return 0;
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}
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req = fuse_get_req(fc);
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if (IS_ERR(req))
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return PTR_ERR(req);
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memset(&outarg, 0, sizeof(outarg));
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req->in.numargs = 0;
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req->in.h.opcode = FUSE_STATFS;
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req->in.h.nodeid = get_node_id(dentry->d_inode);
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req->out.numargs = 1;
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req->out.args[0].size =
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fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
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req->out.args[0].value = &outarg;
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request_send(fc, req);
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err = req->out.h.error;
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if (!err)
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convert_fuse_statfs(buf, &outarg.st);
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fuse_put_request(fc, req);
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return err;
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}
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enum {
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OPT_FD,
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OPT_ROOTMODE,
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OPT_USER_ID,
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OPT_GROUP_ID,
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OPT_DEFAULT_PERMISSIONS,
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OPT_ALLOW_OTHER,
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OPT_MAX_READ,
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OPT_BLKSIZE,
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OPT_ERR
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};
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static match_table_t tokens = {
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{OPT_FD, "fd=%u"},
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{OPT_ROOTMODE, "rootmode=%o"},
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{OPT_USER_ID, "user_id=%u"},
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{OPT_GROUP_ID, "group_id=%u"},
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{OPT_DEFAULT_PERMISSIONS, "default_permissions"},
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{OPT_ALLOW_OTHER, "allow_other"},
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{OPT_MAX_READ, "max_read=%u"},
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{OPT_BLKSIZE, "blksize=%u"},
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{OPT_ERR, NULL}
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};
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static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
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{
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char *p;
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memset(d, 0, sizeof(struct fuse_mount_data));
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d->max_read = ~0;
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d->blksize = 512;
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while ((p = strsep(&opt, ",")) != NULL) {
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int token;
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int value;
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substring_t args[MAX_OPT_ARGS];
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if (!*p)
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continue;
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token = match_token(p, tokens, args);
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switch (token) {
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case OPT_FD:
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if (match_int(&args[0], &value))
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return 0;
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d->fd = value;
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d->fd_present = 1;
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break;
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case OPT_ROOTMODE:
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if (match_octal(&args[0], &value))
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return 0;
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if (!fuse_valid_type(value))
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return 0;
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d->rootmode = value;
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d->rootmode_present = 1;
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break;
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case OPT_USER_ID:
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if (match_int(&args[0], &value))
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return 0;
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d->user_id = value;
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d->user_id_present = 1;
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break;
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case OPT_GROUP_ID:
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if (match_int(&args[0], &value))
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return 0;
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d->group_id = value;
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d->group_id_present = 1;
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break;
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case OPT_DEFAULT_PERMISSIONS:
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d->flags |= FUSE_DEFAULT_PERMISSIONS;
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break;
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case OPT_ALLOW_OTHER:
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d->flags |= FUSE_ALLOW_OTHER;
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break;
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case OPT_MAX_READ:
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if (match_int(&args[0], &value))
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return 0;
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d->max_read = value;
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break;
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case OPT_BLKSIZE:
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if (!is_bdev || match_int(&args[0], &value))
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return 0;
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d->blksize = value;
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break;
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default:
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return 0;
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}
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}
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if (!d->fd_present || !d->rootmode_present ||
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!d->user_id_present || !d->group_id_present)
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return 0;
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return 1;
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}
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static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
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{
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struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
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seq_printf(m, ",user_id=%u", fc->user_id);
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seq_printf(m, ",group_id=%u", fc->group_id);
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if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
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seq_puts(m, ",default_permissions");
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if (fc->flags & FUSE_ALLOW_OTHER)
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seq_puts(m, ",allow_other");
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if (fc->max_read != ~0)
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seq_printf(m, ",max_read=%u", fc->max_read);
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return 0;
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}
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static struct fuse_conn *new_conn(void)
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{
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struct fuse_conn *fc;
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int err;
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fc = kzalloc(sizeof(*fc), GFP_KERNEL);
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if (fc) {
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spin_lock_init(&fc->lock);
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mutex_init(&fc->inst_mutex);
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atomic_set(&fc->count, 1);
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init_waitqueue_head(&fc->waitq);
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init_waitqueue_head(&fc->blocked_waitq);
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init_waitqueue_head(&fc->reserved_req_waitq);
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INIT_LIST_HEAD(&fc->pending);
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INIT_LIST_HEAD(&fc->processing);
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INIT_LIST_HEAD(&fc->io);
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INIT_LIST_HEAD(&fc->interrupts);
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INIT_LIST_HEAD(&fc->bg_queue);
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atomic_set(&fc->num_waiting, 0);
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fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
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fc->bdi.unplug_io_fn = default_unplug_io_fn;
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err = bdi_init(&fc->bdi);
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if (err) {
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kfree(fc);
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fc = NULL;
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goto out;
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}
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fc->reqctr = 0;
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fc->blocked = 1;
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fc->attr_version = 1;
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get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
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}
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out:
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return fc;
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}
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void fuse_conn_put(struct fuse_conn *fc)
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{
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if (atomic_dec_and_test(&fc->count)) {
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if (fc->destroy_req)
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fuse_request_free(fc->destroy_req);
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mutex_destroy(&fc->inst_mutex);
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bdi_destroy(&fc->bdi);
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kfree(fc);
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}
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}
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struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
|
|
{
|
|
atomic_inc(&fc->count);
|
|
return fc;
|
|
}
|
|
|
|
static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
|
|
{
|
|
struct fuse_attr attr;
|
|
memset(&attr, 0, sizeof(attr));
|
|
|
|
attr.mode = mode;
|
|
attr.ino = FUSE_ROOT_ID;
|
|
attr.nlink = 1;
|
|
return fuse_iget(sb, 1, 0, &attr, 0, 0);
|
|
}
|
|
|
|
static const struct super_operations fuse_super_operations = {
|
|
.alloc_inode = fuse_alloc_inode,
|
|
.destroy_inode = fuse_destroy_inode,
|
|
.read_inode = fuse_read_inode,
|
|
.clear_inode = fuse_clear_inode,
|
|
.drop_inode = generic_delete_inode,
|
|
.remount_fs = fuse_remount_fs,
|
|
.put_super = fuse_put_super,
|
|
.umount_begin = fuse_umount_begin,
|
|
.statfs = fuse_statfs,
|
|
.show_options = fuse_show_options,
|
|
};
|
|
|
|
static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
struct fuse_init_out *arg = &req->misc.init_out;
|
|
|
|
if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
|
|
fc->conn_error = 1;
|
|
else {
|
|
unsigned long ra_pages;
|
|
|
|
if (arg->minor >= 6) {
|
|
ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
|
|
if (arg->flags & FUSE_ASYNC_READ)
|
|
fc->async_read = 1;
|
|
if (!(arg->flags & FUSE_POSIX_LOCKS))
|
|
fc->no_lock = 1;
|
|
if (arg->flags & FUSE_ATOMIC_O_TRUNC)
|
|
fc->atomic_o_trunc = 1;
|
|
} else {
|
|
ra_pages = fc->max_read / PAGE_CACHE_SIZE;
|
|
fc->no_lock = 1;
|
|
}
|
|
|
|
fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
|
|
fc->minor = arg->minor;
|
|
fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
|
|
fc->conn_init = 1;
|
|
}
|
|
fuse_put_request(fc, req);
|
|
fc->blocked = 0;
|
|
wake_up_all(&fc->blocked_waitq);
|
|
}
|
|
|
|
static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
|
|
{
|
|
struct fuse_init_in *arg = &req->misc.init_in;
|
|
|
|
arg->major = FUSE_KERNEL_VERSION;
|
|
arg->minor = FUSE_KERNEL_MINOR_VERSION;
|
|
arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
|
|
arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC;
|
|
req->in.h.opcode = FUSE_INIT;
|
|
req->in.numargs = 1;
|
|
req->in.args[0].size = sizeof(*arg);
|
|
req->in.args[0].value = arg;
|
|
req->out.numargs = 1;
|
|
/* Variable length arguement used for backward compatibility
|
|
with interface version < 7.5. Rest of init_out is zeroed
|
|
by do_get_request(), so a short reply is not a problem */
|
|
req->out.argvar = 1;
|
|
req->out.args[0].size = sizeof(struct fuse_init_out);
|
|
req->out.args[0].value = &req->misc.init_out;
|
|
req->end = process_init_reply;
|
|
request_send_background(fc, req);
|
|
}
|
|
|
|
static u64 conn_id(void)
|
|
{
|
|
static u64 ctr = 1;
|
|
return ctr++;
|
|
}
|
|
|
|
static int fuse_fill_super(struct super_block *sb, void *data, int silent)
|
|
{
|
|
struct fuse_conn *fc;
|
|
struct inode *root;
|
|
struct fuse_mount_data d;
|
|
struct file *file;
|
|
struct dentry *root_dentry;
|
|
struct fuse_req *init_req;
|
|
int err;
|
|
int is_bdev = sb->s_bdev != NULL;
|
|
|
|
if (sb->s_flags & MS_MANDLOCK)
|
|
return -EINVAL;
|
|
|
|
if (!parse_fuse_opt((char *) data, &d, is_bdev))
|
|
return -EINVAL;
|
|
|
|
if (is_bdev) {
|
|
#ifdef CONFIG_BLOCK
|
|
if (!sb_set_blocksize(sb, d.blksize))
|
|
return -EINVAL;
|
|
#endif
|
|
} else {
|
|
sb->s_blocksize = PAGE_CACHE_SIZE;
|
|
sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
|
|
}
|
|
sb->s_magic = FUSE_SUPER_MAGIC;
|
|
sb->s_op = &fuse_super_operations;
|
|
sb->s_maxbytes = MAX_LFS_FILESIZE;
|
|
|
|
file = fget(d.fd);
|
|
if (!file)
|
|
return -EINVAL;
|
|
|
|
if (file->f_op != &fuse_dev_operations)
|
|
return -EINVAL;
|
|
|
|
fc = new_conn();
|
|
if (!fc)
|
|
return -ENOMEM;
|
|
|
|
fc->flags = d.flags;
|
|
fc->user_id = d.user_id;
|
|
fc->group_id = d.group_id;
|
|
fc->max_read = d.max_read;
|
|
|
|
/* Used by get_root_inode() */
|
|
sb->s_fs_info = fc;
|
|
|
|
err = -ENOMEM;
|
|
root = get_root_inode(sb, d.rootmode);
|
|
if (!root)
|
|
goto err;
|
|
|
|
root_dentry = d_alloc_root(root);
|
|
if (!root_dentry) {
|
|
iput(root);
|
|
goto err;
|
|
}
|
|
|
|
init_req = fuse_request_alloc();
|
|
if (!init_req)
|
|
goto err_put_root;
|
|
|
|
if (is_bdev) {
|
|
fc->destroy_req = fuse_request_alloc();
|
|
if (!fc->destroy_req)
|
|
goto err_put_root;
|
|
}
|
|
|
|
mutex_lock(&fuse_mutex);
|
|
err = -EINVAL;
|
|
if (file->private_data)
|
|
goto err_unlock;
|
|
|
|
fc->id = conn_id();
|
|
err = fuse_ctl_add_conn(fc);
|
|
if (err)
|
|
goto err_unlock;
|
|
|
|
list_add_tail(&fc->entry, &fuse_conn_list);
|
|
sb->s_root = root_dentry;
|
|
fc->connected = 1;
|
|
file->private_data = fuse_conn_get(fc);
|
|
mutex_unlock(&fuse_mutex);
|
|
/*
|
|
* atomic_dec_and_test() in fput() provides the necessary
|
|
* memory barrier for file->private_data to be visible on all
|
|
* CPUs after this
|
|
*/
|
|
fput(file);
|
|
|
|
fuse_send_init(fc, init_req);
|
|
|
|
return 0;
|
|
|
|
err_unlock:
|
|
mutex_unlock(&fuse_mutex);
|
|
fuse_request_free(init_req);
|
|
err_put_root:
|
|
dput(root_dentry);
|
|
err:
|
|
fput(file);
|
|
fuse_conn_put(fc);
|
|
return err;
|
|
}
|
|
|
|
static int fuse_get_sb(struct file_system_type *fs_type,
|
|
int flags, const char *dev_name,
|
|
void *raw_data, struct vfsmount *mnt)
|
|
{
|
|
return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
|
|
}
|
|
|
|
static struct file_system_type fuse_fs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = "fuse",
|
|
.fs_flags = FS_HAS_SUBTYPE,
|
|
.get_sb = fuse_get_sb,
|
|
.kill_sb = kill_anon_super,
|
|
};
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
static int fuse_get_sb_blk(struct file_system_type *fs_type,
|
|
int flags, const char *dev_name,
|
|
void *raw_data, struct vfsmount *mnt)
|
|
{
|
|
return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
|
|
mnt);
|
|
}
|
|
|
|
static struct file_system_type fuseblk_fs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = "fuseblk",
|
|
.get_sb = fuse_get_sb_blk,
|
|
.kill_sb = kill_block_super,
|
|
.fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
|
|
};
|
|
|
|
static inline int register_fuseblk(void)
|
|
{
|
|
return register_filesystem(&fuseblk_fs_type);
|
|
}
|
|
|
|
static inline void unregister_fuseblk(void)
|
|
{
|
|
unregister_filesystem(&fuseblk_fs_type);
|
|
}
|
|
#else
|
|
static inline int register_fuseblk(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void unregister_fuseblk(void)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
static void fuse_inode_init_once(struct kmem_cache *cachep, void *foo)
|
|
{
|
|
struct inode * inode = foo;
|
|
|
|
inode_init_once(inode);
|
|
}
|
|
|
|
static int __init fuse_fs_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = register_filesystem(&fuse_fs_type);
|
|
if (err)
|
|
goto out;
|
|
|
|
err = register_fuseblk();
|
|
if (err)
|
|
goto out_unreg;
|
|
|
|
fuse_inode_cachep = kmem_cache_create("fuse_inode",
|
|
sizeof(struct fuse_inode),
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
fuse_inode_init_once);
|
|
err = -ENOMEM;
|
|
if (!fuse_inode_cachep)
|
|
goto out_unreg2;
|
|
|
|
return 0;
|
|
|
|
out_unreg2:
|
|
unregister_fuseblk();
|
|
out_unreg:
|
|
unregister_filesystem(&fuse_fs_type);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void fuse_fs_cleanup(void)
|
|
{
|
|
unregister_filesystem(&fuse_fs_type);
|
|
unregister_fuseblk();
|
|
kmem_cache_destroy(fuse_inode_cachep);
|
|
}
|
|
|
|
static struct kobject *fuse_kobj;
|
|
static struct kobject *connections_kobj;
|
|
|
|
static int fuse_sysfs_init(void)
|
|
{
|
|
int err;
|
|
|
|
fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
|
|
if (!fuse_kobj) {
|
|
err = -ENOMEM;
|
|
goto out_err;
|
|
}
|
|
|
|
connections_kobj = kobject_create_and_add("connections", fuse_kobj);
|
|
if (!connections_kobj) {
|
|
err = -ENOMEM;
|
|
goto out_fuse_unregister;
|
|
}
|
|
|
|
return 0;
|
|
|
|
out_fuse_unregister:
|
|
kobject_put(fuse_kobj);
|
|
out_err:
|
|
return err;
|
|
}
|
|
|
|
static void fuse_sysfs_cleanup(void)
|
|
{
|
|
kobject_put(connections_kobj);
|
|
kobject_put(fuse_kobj);
|
|
}
|
|
|
|
static int __init fuse_init(void)
|
|
{
|
|
int res;
|
|
|
|
printk("fuse init (API version %i.%i)\n",
|
|
FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
|
|
|
|
INIT_LIST_HEAD(&fuse_conn_list);
|
|
res = fuse_fs_init();
|
|
if (res)
|
|
goto err;
|
|
|
|
res = fuse_dev_init();
|
|
if (res)
|
|
goto err_fs_cleanup;
|
|
|
|
res = fuse_sysfs_init();
|
|
if (res)
|
|
goto err_dev_cleanup;
|
|
|
|
res = fuse_ctl_init();
|
|
if (res)
|
|
goto err_sysfs_cleanup;
|
|
|
|
return 0;
|
|
|
|
err_sysfs_cleanup:
|
|
fuse_sysfs_cleanup();
|
|
err_dev_cleanup:
|
|
fuse_dev_cleanup();
|
|
err_fs_cleanup:
|
|
fuse_fs_cleanup();
|
|
err:
|
|
return res;
|
|
}
|
|
|
|
static void __exit fuse_exit(void)
|
|
{
|
|
printk(KERN_DEBUG "fuse exit\n");
|
|
|
|
fuse_ctl_cleanup();
|
|
fuse_sysfs_cleanup();
|
|
fuse_fs_cleanup();
|
|
fuse_dev_cleanup();
|
|
}
|
|
|
|
module_init(fuse_init);
|
|
module_exit(fuse_exit);
|