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![Miklos Szeredi](/assets/img/avatar_default.png)
Virtio-fs does not accept any mount options, so it's confusing and wrong to show any in /proc/mounts. Reported-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
1522 lines
35 KiB
C
1522 lines
35 KiB
C
/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2008 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/moduleparam.h>
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#include <linux/fs_context.h>
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#include <linux/fs_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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#include <linux/exportfs.h>
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#include <linux/posix_acl.h>
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#include <linux/pid_namespace.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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static int set_global_limit(const char *val, const struct kernel_param *kp);
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unsigned max_user_bgreq;
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module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
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&max_user_bgreq, 0644);
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__MODULE_PARM_TYPE(max_user_bgreq, "uint");
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MODULE_PARM_DESC(max_user_bgreq,
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"Global limit for the maximum number of backgrounded requests an "
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"unprivileged user can set");
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unsigned max_user_congthresh;
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module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
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&max_user_congthresh, 0644);
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__MODULE_PARM_TYPE(max_user_congthresh, "uint");
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MODULE_PARM_DESC(max_user_congthresh,
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"Global limit for the maximum congestion threshold an "
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"unprivileged user can set");
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#define FUSE_SUPER_MAGIC 0x65735546
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#define FUSE_DEFAULT_BLKSIZE 512
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/** Maximum number of outstanding background requests */
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#define FUSE_DEFAULT_MAX_BACKGROUND 12
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/** Congestion starts at 75% of maximum */
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#define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
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#ifdef CONFIG_BLOCK
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static struct file_system_type fuseblk_fs_type;
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#endif
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struct fuse_forget_link *fuse_alloc_forget(void)
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{
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return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL_ACCOUNT);
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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 fuse_inode *fi;
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fi = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
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if (!fi)
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return NULL;
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fi->i_time = 0;
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fi->inval_mask = 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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fi->orig_ino = 0;
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fi->state = 0;
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mutex_init(&fi->mutex);
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spin_lock_init(&fi->lock);
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fi->forget = fuse_alloc_forget();
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if (!fi->forget) {
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kmem_cache_free(fuse_inode_cachep, fi);
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return NULL;
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}
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return &fi->inode;
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}
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static void fuse_free_inode(struct inode *inode)
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{
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struct fuse_inode *fi = get_fuse_inode(inode);
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mutex_destroy(&fi->mutex);
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kfree(fi->forget);
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kmem_cache_free(fuse_inode_cachep, fi);
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}
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static void fuse_evict_inode(struct inode *inode)
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{
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struct fuse_inode *fi = get_fuse_inode(inode);
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truncate_inode_pages_final(&inode->i_data);
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clear_inode(inode);
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if (inode->i_sb->s_flags & SB_ACTIVE) {
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struct fuse_conn *fc = get_fuse_conn(inode);
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fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup);
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fi->forget = NULL;
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}
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if (S_ISREG(inode->i_mode) && !is_bad_inode(inode)) {
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WARN_ON(!list_empty(&fi->write_files));
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WARN_ON(!list_empty(&fi->queued_writes));
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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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sync_filesystem(sb);
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if (*flags & SB_MANDLOCK)
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return -EINVAL;
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return 0;
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}
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/*
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* ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down
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* so that it will fit.
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*/
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static ino_t fuse_squash_ino(u64 ino64)
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{
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ino_t ino = (ino_t) ino64;
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if (sizeof(ino_t) < sizeof(u64))
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ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8;
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return ino;
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}
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void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
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u64 attr_valid)
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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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lockdep_assert_held(&fi->lock);
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fi->attr_version = atomic64_inc_return(&fc->attr_version);
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fi->i_time = attr_valid;
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WRITE_ONCE(fi->inval_mask, 0);
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inode->i_ino = fuse_squash_ino(attr->ino);
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inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
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set_nlink(inode, attr->nlink);
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inode->i_uid = make_kuid(fc->user_ns, attr->uid);
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inode->i_gid = make_kgid(fc->user_ns, 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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/* mtime from server may be stale due to local buffered write */
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if (!fc->writeback_cache || !S_ISREG(inode->i_mode)) {
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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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}
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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->default_permissions)
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inode->i_mode &= ~S_ISVTX;
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fi->orig_ino = attr->ino;
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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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bool is_wb = fc->writeback_cache;
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loff_t oldsize;
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struct timespec64 old_mtime;
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spin_lock(&fi->lock);
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if ((attr_version != 0 && fi->attr_version > attr_version) ||
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test_bit(FUSE_I_SIZE_UNSTABLE, &fi->state)) {
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spin_unlock(&fi->lock);
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return;
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}
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old_mtime = inode->i_mtime;
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fuse_change_attributes_common(inode, attr, attr_valid);
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oldsize = inode->i_size;
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/*
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* In case of writeback_cache enabled, the cached writes beyond EOF
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* extend local i_size without keeping userspace server in sync. So,
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* attr->size coming from server can be stale. We cannot trust it.
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*/
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if (!is_wb || !S_ISREG(inode->i_mode))
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i_size_write(inode, attr->size);
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spin_unlock(&fi->lock);
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if (!is_wb && S_ISREG(inode->i_mode)) {
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bool inval = false;
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if (oldsize != attr->size) {
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truncate_pagecache(inode, attr->size);
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if (!fc->explicit_inval_data)
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inval = true;
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} else if (fc->auto_inval_data) {
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struct timespec64 new_mtime = {
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.tv_sec = attr->mtime,
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.tv_nsec = attr->mtimensec,
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};
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/*
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* Auto inval mode also checks and invalidates if mtime
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* has changed.
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*/
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if (!timespec64_equal(&old_mtime, &new_mtime))
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inval = true;
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}
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if (inval)
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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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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 (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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int fuse_inode_eq(struct inode *inode, void *_nodeidp)
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{
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u64 nodeid = *(u64 *) _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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u64 nodeid = *(u64 *) _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, u64 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;
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if (!fc->writeback_cache || !S_ISREG(attr->mode))
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inode->i_flags |= S_NOCMTIME;
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inode->i_generation = generation;
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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(&fi->lock);
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fi->nlookup++;
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spin_unlock(&fi->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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int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
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loff_t offset, loff_t len)
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{
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struct inode *inode;
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pgoff_t pg_start;
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pgoff_t pg_end;
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inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
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if (!inode)
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return -ENOENT;
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fuse_invalidate_attr(inode);
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forget_all_cached_acls(inode);
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if (offset >= 0) {
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pg_start = offset >> PAGE_SHIFT;
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if (len <= 0)
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pg_end = -1;
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else
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pg_end = (offset + len - 1) >> PAGE_SHIFT;
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invalidate_inode_pages2_range(inode->i_mapping,
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pg_start, pg_end);
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}
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iput(inode);
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return 0;
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}
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bool fuse_lock_inode(struct inode *inode)
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{
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bool locked = false;
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if (!get_fuse_conn(inode)->parallel_dirops) {
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mutex_lock(&get_fuse_inode(inode)->mutex);
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locked = true;
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}
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return locked;
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}
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void fuse_unlock_inode(struct inode *inode, bool locked)
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{
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if (locked)
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mutex_unlock(&get_fuse_inode(inode)->mutex);
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}
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static void fuse_umount_begin(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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if (!fc->no_force_umount)
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fuse_abort_conn(fc);
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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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if (fc->conn_init) {
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FUSE_ARGS(args);
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args.opcode = FUSE_DESTROY;
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args.force = true;
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args.nocreds = true;
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fuse_simple_request(fc, &args);
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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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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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FUSE_ARGS(args);
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struct fuse_statfs_out outarg;
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int err;
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if (!fuse_allow_current_process(fc)) {
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buf->f_type = FUSE_SUPER_MAGIC;
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return 0;
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}
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memset(&outarg, 0, sizeof(outarg));
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args.in_numargs = 0;
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args.opcode = FUSE_STATFS;
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args.nodeid = get_node_id(d_inode(dentry));
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args.out_numargs = 1;
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args.out_args[0].size = sizeof(outarg);
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args.out_args[0].value = &outarg;
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err = fuse_simple_request(fc, &args);
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if (!err)
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convert_fuse_statfs(buf, &outarg.st);
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return err;
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}
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enum {
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OPT_SOURCE,
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OPT_SUBTYPE,
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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 const struct fs_parameter_spec fuse_param_specs[] = {
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fsparam_string ("source", OPT_SOURCE),
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fsparam_u32 ("fd", OPT_FD),
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fsparam_u32oct ("rootmode", OPT_ROOTMODE),
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fsparam_u32 ("user_id", OPT_USER_ID),
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fsparam_u32 ("group_id", OPT_GROUP_ID),
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fsparam_flag ("default_permissions", OPT_DEFAULT_PERMISSIONS),
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fsparam_flag ("allow_other", OPT_ALLOW_OTHER),
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fsparam_u32 ("max_read", OPT_MAX_READ),
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fsparam_u32 ("blksize", OPT_BLKSIZE),
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fsparam_string ("subtype", OPT_SUBTYPE),
|
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{}
|
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};
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|
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static const struct fs_parameter_description fuse_fs_parameters = {
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.name = "fuse",
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.specs = fuse_param_specs,
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};
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|
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static int fuse_parse_param(struct fs_context *fc, struct fs_parameter *param)
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{
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struct fs_parse_result result;
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struct fuse_fs_context *ctx = fc->fs_private;
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int opt;
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opt = fs_parse(fc, &fuse_fs_parameters, param, &result);
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if (opt < 0)
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return opt;
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|
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switch (opt) {
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case OPT_SOURCE:
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if (fc->source)
|
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return invalf(fc, "fuse: Multiple sources specified");
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fc->source = param->string;
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param->string = NULL;
|
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break;
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|
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case OPT_SUBTYPE:
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if (ctx->subtype)
|
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return invalf(fc, "fuse: Multiple subtypes specified");
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ctx->subtype = param->string;
|
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param->string = NULL;
|
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return 0;
|
|
|
|
case OPT_FD:
|
|
ctx->fd = result.uint_32;
|
|
ctx->fd_present = 1;
|
|
break;
|
|
|
|
case OPT_ROOTMODE:
|
|
if (!fuse_valid_type(result.uint_32))
|
|
return invalf(fc, "fuse: Invalid rootmode");
|
|
ctx->rootmode = result.uint_32;
|
|
ctx->rootmode_present = 1;
|
|
break;
|
|
|
|
case OPT_USER_ID:
|
|
ctx->user_id = make_kuid(fc->user_ns, result.uint_32);
|
|
if (!uid_valid(ctx->user_id))
|
|
return invalf(fc, "fuse: Invalid user_id");
|
|
ctx->user_id_present = 1;
|
|
break;
|
|
|
|
case OPT_GROUP_ID:
|
|
ctx->group_id = make_kgid(fc->user_ns, result.uint_32);
|
|
if (!gid_valid(ctx->group_id))
|
|
return invalf(fc, "fuse: Invalid group_id");
|
|
ctx->group_id_present = 1;
|
|
break;
|
|
|
|
case OPT_DEFAULT_PERMISSIONS:
|
|
ctx->default_permissions = 1;
|
|
break;
|
|
|
|
case OPT_ALLOW_OTHER:
|
|
ctx->allow_other = 1;
|
|
break;
|
|
|
|
case OPT_MAX_READ:
|
|
ctx->max_read = result.uint_32;
|
|
break;
|
|
|
|
case OPT_BLKSIZE:
|
|
if (!ctx->is_bdev)
|
|
return invalf(fc, "fuse: blksize only supported for fuseblk");
|
|
ctx->blksize = result.uint_32;
|
|
break;
|
|
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_free_fc(struct fs_context *fc)
|
|
{
|
|
struct fuse_fs_context *ctx = fc->fs_private;
|
|
|
|
if (ctx) {
|
|
kfree(ctx->subtype);
|
|
kfree(ctx);
|
|
}
|
|
}
|
|
|
|
static int fuse_show_options(struct seq_file *m, struct dentry *root)
|
|
{
|
|
struct super_block *sb = root->d_sb;
|
|
struct fuse_conn *fc = get_fuse_conn_super(sb);
|
|
|
|
if (fc->no_mount_options)
|
|
return 0;
|
|
|
|
seq_printf(m, ",user_id=%u", from_kuid_munged(fc->user_ns, fc->user_id));
|
|
seq_printf(m, ",group_id=%u", from_kgid_munged(fc->user_ns, fc->group_id));
|
|
if (fc->default_permissions)
|
|
seq_puts(m, ",default_permissions");
|
|
if (fc->allow_other)
|
|
seq_puts(m, ",allow_other");
|
|
if (fc->max_read != ~0)
|
|
seq_printf(m, ",max_read=%u", fc->max_read);
|
|
if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
|
|
seq_printf(m, ",blksize=%lu", sb->s_blocksize);
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_iqueue_init(struct fuse_iqueue *fiq,
|
|
const struct fuse_iqueue_ops *ops,
|
|
void *priv)
|
|
{
|
|
memset(fiq, 0, sizeof(struct fuse_iqueue));
|
|
spin_lock_init(&fiq->lock);
|
|
init_waitqueue_head(&fiq->waitq);
|
|
INIT_LIST_HEAD(&fiq->pending);
|
|
INIT_LIST_HEAD(&fiq->interrupts);
|
|
fiq->forget_list_tail = &fiq->forget_list_head;
|
|
fiq->connected = 1;
|
|
fiq->ops = ops;
|
|
fiq->priv = priv;
|
|
}
|
|
|
|
static void fuse_pqueue_init(struct fuse_pqueue *fpq)
|
|
{
|
|
unsigned int i;
|
|
|
|
spin_lock_init(&fpq->lock);
|
|
for (i = 0; i < FUSE_PQ_HASH_SIZE; i++)
|
|
INIT_LIST_HEAD(&fpq->processing[i]);
|
|
INIT_LIST_HEAD(&fpq->io);
|
|
fpq->connected = 1;
|
|
}
|
|
|
|
void fuse_conn_init(struct fuse_conn *fc, struct user_namespace *user_ns,
|
|
const struct fuse_iqueue_ops *fiq_ops, void *fiq_priv)
|
|
{
|
|
memset(fc, 0, sizeof(*fc));
|
|
spin_lock_init(&fc->lock);
|
|
spin_lock_init(&fc->bg_lock);
|
|
init_rwsem(&fc->killsb);
|
|
refcount_set(&fc->count, 1);
|
|
atomic_set(&fc->dev_count, 1);
|
|
init_waitqueue_head(&fc->blocked_waitq);
|
|
fuse_iqueue_init(&fc->iq, fiq_ops, fiq_priv);
|
|
INIT_LIST_HEAD(&fc->bg_queue);
|
|
INIT_LIST_HEAD(&fc->entry);
|
|
INIT_LIST_HEAD(&fc->devices);
|
|
atomic_set(&fc->num_waiting, 0);
|
|
fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
|
|
fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
|
|
atomic64_set(&fc->khctr, 0);
|
|
fc->polled_files = RB_ROOT;
|
|
fc->blocked = 0;
|
|
fc->initialized = 0;
|
|
fc->connected = 1;
|
|
atomic64_set(&fc->attr_version, 1);
|
|
get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
|
|
fc->pid_ns = get_pid_ns(task_active_pid_ns(current));
|
|
fc->user_ns = get_user_ns(user_ns);
|
|
fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_conn_init);
|
|
|
|
void fuse_conn_put(struct fuse_conn *fc)
|
|
{
|
|
if (refcount_dec_and_test(&fc->count)) {
|
|
struct fuse_iqueue *fiq = &fc->iq;
|
|
|
|
if (fiq->ops->release)
|
|
fiq->ops->release(fiq);
|
|
put_pid_ns(fc->pid_ns);
|
|
put_user_ns(fc->user_ns);
|
|
fc->release(fc);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_conn_put);
|
|
|
|
struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
|
|
{
|
|
refcount_inc(&fc->count);
|
|
return fc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_conn_get);
|
|
|
|
static struct inode *fuse_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);
|
|
}
|
|
|
|
struct fuse_inode_handle {
|
|
u64 nodeid;
|
|
u32 generation;
|
|
};
|
|
|
|
static struct dentry *fuse_get_dentry(struct super_block *sb,
|
|
struct fuse_inode_handle *handle)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn_super(sb);
|
|
struct inode *inode;
|
|
struct dentry *entry;
|
|
int err = -ESTALE;
|
|
|
|
if (handle->nodeid == 0)
|
|
goto out_err;
|
|
|
|
inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
|
|
if (!inode) {
|
|
struct fuse_entry_out outarg;
|
|
const struct qstr name = QSTR_INIT(".", 1);
|
|
|
|
if (!fc->export_support)
|
|
goto out_err;
|
|
|
|
err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
|
|
&inode);
|
|
if (err && err != -ENOENT)
|
|
goto out_err;
|
|
if (err || !inode) {
|
|
err = -ESTALE;
|
|
goto out_err;
|
|
}
|
|
err = -EIO;
|
|
if (get_node_id(inode) != handle->nodeid)
|
|
goto out_iput;
|
|
}
|
|
err = -ESTALE;
|
|
if (inode->i_generation != handle->generation)
|
|
goto out_iput;
|
|
|
|
entry = d_obtain_alias(inode);
|
|
if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
|
|
fuse_invalidate_entry_cache(entry);
|
|
|
|
return entry;
|
|
|
|
out_iput:
|
|
iput(inode);
|
|
out_err:
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
static int fuse_encode_fh(struct inode *inode, u32 *fh, int *max_len,
|
|
struct inode *parent)
|
|
{
|
|
int len = parent ? 6 : 3;
|
|
u64 nodeid;
|
|
u32 generation;
|
|
|
|
if (*max_len < len) {
|
|
*max_len = len;
|
|
return FILEID_INVALID;
|
|
}
|
|
|
|
nodeid = get_fuse_inode(inode)->nodeid;
|
|
generation = inode->i_generation;
|
|
|
|
fh[0] = (u32)(nodeid >> 32);
|
|
fh[1] = (u32)(nodeid & 0xffffffff);
|
|
fh[2] = generation;
|
|
|
|
if (parent) {
|
|
nodeid = get_fuse_inode(parent)->nodeid;
|
|
generation = parent->i_generation;
|
|
|
|
fh[3] = (u32)(nodeid >> 32);
|
|
fh[4] = (u32)(nodeid & 0xffffffff);
|
|
fh[5] = generation;
|
|
}
|
|
|
|
*max_len = len;
|
|
return parent ? 0x82 : 0x81;
|
|
}
|
|
|
|
static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
|
|
struct fid *fid, int fh_len, int fh_type)
|
|
{
|
|
struct fuse_inode_handle handle;
|
|
|
|
if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
|
|
return NULL;
|
|
|
|
handle.nodeid = (u64) fid->raw[0] << 32;
|
|
handle.nodeid |= (u64) fid->raw[1];
|
|
handle.generation = fid->raw[2];
|
|
return fuse_get_dentry(sb, &handle);
|
|
}
|
|
|
|
static struct dentry *fuse_fh_to_parent(struct super_block *sb,
|
|
struct fid *fid, int fh_len, int fh_type)
|
|
{
|
|
struct fuse_inode_handle parent;
|
|
|
|
if (fh_type != 0x82 || fh_len < 6)
|
|
return NULL;
|
|
|
|
parent.nodeid = (u64) fid->raw[3] << 32;
|
|
parent.nodeid |= (u64) fid->raw[4];
|
|
parent.generation = fid->raw[5];
|
|
return fuse_get_dentry(sb, &parent);
|
|
}
|
|
|
|
static struct dentry *fuse_get_parent(struct dentry *child)
|
|
{
|
|
struct inode *child_inode = d_inode(child);
|
|
struct fuse_conn *fc = get_fuse_conn(child_inode);
|
|
struct inode *inode;
|
|
struct dentry *parent;
|
|
struct fuse_entry_out outarg;
|
|
const struct qstr name = QSTR_INIT("..", 2);
|
|
int err;
|
|
|
|
if (!fc->export_support)
|
|
return ERR_PTR(-ESTALE);
|
|
|
|
err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
|
|
&name, &outarg, &inode);
|
|
if (err) {
|
|
if (err == -ENOENT)
|
|
return ERR_PTR(-ESTALE);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
parent = d_obtain_alias(inode);
|
|
if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
|
|
fuse_invalidate_entry_cache(parent);
|
|
|
|
return parent;
|
|
}
|
|
|
|
static const struct export_operations fuse_export_operations = {
|
|
.fh_to_dentry = fuse_fh_to_dentry,
|
|
.fh_to_parent = fuse_fh_to_parent,
|
|
.encode_fh = fuse_encode_fh,
|
|
.get_parent = fuse_get_parent,
|
|
};
|
|
|
|
static const struct super_operations fuse_super_operations = {
|
|
.alloc_inode = fuse_alloc_inode,
|
|
.free_inode = fuse_free_inode,
|
|
.evict_inode = fuse_evict_inode,
|
|
.write_inode = fuse_write_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 sanitize_global_limit(unsigned *limit)
|
|
{
|
|
/*
|
|
* The default maximum number of async requests is calculated to consume
|
|
* 1/2^13 of the total memory, assuming 392 bytes per request.
|
|
*/
|
|
if (*limit == 0)
|
|
*limit = ((totalram_pages() << PAGE_SHIFT) >> 13) / 392;
|
|
|
|
if (*limit >= 1 << 16)
|
|
*limit = (1 << 16) - 1;
|
|
}
|
|
|
|
static int set_global_limit(const char *val, const struct kernel_param *kp)
|
|
{
|
|
int rv;
|
|
|
|
rv = param_set_uint(val, kp);
|
|
if (rv)
|
|
return rv;
|
|
|
|
sanitize_global_limit((unsigned *)kp->arg);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
|
|
{
|
|
int cap_sys_admin = capable(CAP_SYS_ADMIN);
|
|
|
|
if (arg->minor < 13)
|
|
return;
|
|
|
|
sanitize_global_limit(&max_user_bgreq);
|
|
sanitize_global_limit(&max_user_congthresh);
|
|
|
|
spin_lock(&fc->bg_lock);
|
|
if (arg->max_background) {
|
|
fc->max_background = arg->max_background;
|
|
|
|
if (!cap_sys_admin && fc->max_background > max_user_bgreq)
|
|
fc->max_background = max_user_bgreq;
|
|
}
|
|
if (arg->congestion_threshold) {
|
|
fc->congestion_threshold = arg->congestion_threshold;
|
|
|
|
if (!cap_sys_admin &&
|
|
fc->congestion_threshold > max_user_congthresh)
|
|
fc->congestion_threshold = max_user_congthresh;
|
|
}
|
|
spin_unlock(&fc->bg_lock);
|
|
}
|
|
|
|
struct fuse_init_args {
|
|
struct fuse_args args;
|
|
struct fuse_init_in in;
|
|
struct fuse_init_out out;
|
|
};
|
|
|
|
static void process_init_reply(struct fuse_conn *fc, struct fuse_args *args,
|
|
int error)
|
|
{
|
|
struct fuse_init_args *ia = container_of(args, typeof(*ia), args);
|
|
struct fuse_init_out *arg = &ia->out;
|
|
|
|
if (error || arg->major != FUSE_KERNEL_VERSION)
|
|
fc->conn_error = 1;
|
|
else {
|
|
unsigned long ra_pages;
|
|
|
|
process_init_limits(fc, arg);
|
|
|
|
if (arg->minor >= 6) {
|
|
ra_pages = arg->max_readahead / PAGE_SIZE;
|
|
if (arg->flags & FUSE_ASYNC_READ)
|
|
fc->async_read = 1;
|
|
if (!(arg->flags & FUSE_POSIX_LOCKS))
|
|
fc->no_lock = 1;
|
|
if (arg->minor >= 17) {
|
|
if (!(arg->flags & FUSE_FLOCK_LOCKS))
|
|
fc->no_flock = 1;
|
|
} else {
|
|
if (!(arg->flags & FUSE_POSIX_LOCKS))
|
|
fc->no_flock = 1;
|
|
}
|
|
if (arg->flags & FUSE_ATOMIC_O_TRUNC)
|
|
fc->atomic_o_trunc = 1;
|
|
if (arg->minor >= 9) {
|
|
/* LOOKUP has dependency on proto version */
|
|
if (arg->flags & FUSE_EXPORT_SUPPORT)
|
|
fc->export_support = 1;
|
|
}
|
|
if (arg->flags & FUSE_BIG_WRITES)
|
|
fc->big_writes = 1;
|
|
if (arg->flags & FUSE_DONT_MASK)
|
|
fc->dont_mask = 1;
|
|
if (arg->flags & FUSE_AUTO_INVAL_DATA)
|
|
fc->auto_inval_data = 1;
|
|
else if (arg->flags & FUSE_EXPLICIT_INVAL_DATA)
|
|
fc->explicit_inval_data = 1;
|
|
if (arg->flags & FUSE_DO_READDIRPLUS) {
|
|
fc->do_readdirplus = 1;
|
|
if (arg->flags & FUSE_READDIRPLUS_AUTO)
|
|
fc->readdirplus_auto = 1;
|
|
}
|
|
if (arg->flags & FUSE_ASYNC_DIO)
|
|
fc->async_dio = 1;
|
|
if (arg->flags & FUSE_WRITEBACK_CACHE)
|
|
fc->writeback_cache = 1;
|
|
if (arg->flags & FUSE_PARALLEL_DIROPS)
|
|
fc->parallel_dirops = 1;
|
|
if (arg->flags & FUSE_HANDLE_KILLPRIV)
|
|
fc->handle_killpriv = 1;
|
|
if (arg->time_gran && arg->time_gran <= 1000000000)
|
|
fc->sb->s_time_gran = arg->time_gran;
|
|
if ((arg->flags & FUSE_POSIX_ACL)) {
|
|
fc->default_permissions = 1;
|
|
fc->posix_acl = 1;
|
|
fc->sb->s_xattr = fuse_acl_xattr_handlers;
|
|
}
|
|
if (arg->flags & FUSE_CACHE_SYMLINKS)
|
|
fc->cache_symlinks = 1;
|
|
if (arg->flags & FUSE_ABORT_ERROR)
|
|
fc->abort_err = 1;
|
|
if (arg->flags & FUSE_MAX_PAGES) {
|
|
fc->max_pages =
|
|
min_t(unsigned int, FUSE_MAX_MAX_PAGES,
|
|
max_t(unsigned int, arg->max_pages, 1));
|
|
}
|
|
} else {
|
|
ra_pages = fc->max_read / PAGE_SIZE;
|
|
fc->no_lock = 1;
|
|
fc->no_flock = 1;
|
|
}
|
|
|
|
fc->sb->s_bdi->ra_pages =
|
|
min(fc->sb->s_bdi->ra_pages, ra_pages);
|
|
fc->minor = arg->minor;
|
|
fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
|
|
fc->max_write = max_t(unsigned, 4096, fc->max_write);
|
|
fc->conn_init = 1;
|
|
}
|
|
kfree(ia);
|
|
|
|
fuse_set_initialized(fc);
|
|
wake_up_all(&fc->blocked_waitq);
|
|
}
|
|
|
|
void fuse_send_init(struct fuse_conn *fc)
|
|
{
|
|
struct fuse_init_args *ia;
|
|
|
|
ia = kzalloc(sizeof(*ia), GFP_KERNEL | __GFP_NOFAIL);
|
|
|
|
ia->in.major = FUSE_KERNEL_VERSION;
|
|
ia->in.minor = FUSE_KERNEL_MINOR_VERSION;
|
|
ia->in.max_readahead = fc->sb->s_bdi->ra_pages * PAGE_SIZE;
|
|
ia->in.flags |=
|
|
FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
|
|
FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
|
|
FUSE_SPLICE_WRITE | FUSE_SPLICE_MOVE | FUSE_SPLICE_READ |
|
|
FUSE_FLOCK_LOCKS | FUSE_HAS_IOCTL_DIR | FUSE_AUTO_INVAL_DATA |
|
|
FUSE_DO_READDIRPLUS | FUSE_READDIRPLUS_AUTO | FUSE_ASYNC_DIO |
|
|
FUSE_WRITEBACK_CACHE | FUSE_NO_OPEN_SUPPORT |
|
|
FUSE_PARALLEL_DIROPS | FUSE_HANDLE_KILLPRIV | FUSE_POSIX_ACL |
|
|
FUSE_ABORT_ERROR | FUSE_MAX_PAGES | FUSE_CACHE_SYMLINKS |
|
|
FUSE_NO_OPENDIR_SUPPORT | FUSE_EXPLICIT_INVAL_DATA;
|
|
ia->args.opcode = FUSE_INIT;
|
|
ia->args.in_numargs = 1;
|
|
ia->args.in_args[0].size = sizeof(ia->in);
|
|
ia->args.in_args[0].value = &ia->in;
|
|
ia->args.out_numargs = 1;
|
|
/* Variable length argument 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 */
|
|
ia->args.out_argvar = 1;
|
|
ia->args.out_args[0].size = sizeof(ia->out);
|
|
ia->args.out_args[0].value = &ia->out;
|
|
ia->args.force = true;
|
|
ia->args.nocreds = true;
|
|
ia->args.end = process_init_reply;
|
|
|
|
if (fuse_simple_background(fc, &ia->args, GFP_KERNEL) != 0)
|
|
process_init_reply(fc, &ia->args, -ENOTCONN);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_send_init);
|
|
|
|
void fuse_free_conn(struct fuse_conn *fc)
|
|
{
|
|
WARN_ON(!list_empty(&fc->devices));
|
|
kfree_rcu(fc, rcu);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_free_conn);
|
|
|
|
static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
|
|
{
|
|
int err;
|
|
char *suffix = "";
|
|
|
|
if (sb->s_bdev) {
|
|
suffix = "-fuseblk";
|
|
/*
|
|
* sb->s_bdi points to blkdev's bdi however we want to redirect
|
|
* it to our private bdi...
|
|
*/
|
|
bdi_put(sb->s_bdi);
|
|
sb->s_bdi = &noop_backing_dev_info;
|
|
}
|
|
err = super_setup_bdi_name(sb, "%u:%u%s", MAJOR(fc->dev),
|
|
MINOR(fc->dev), suffix);
|
|
if (err)
|
|
return err;
|
|
|
|
sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
|
|
/* fuse does it's own writeback accounting */
|
|
sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
|
|
|
|
/*
|
|
* For a single fuse filesystem use max 1% of dirty +
|
|
* writeback threshold.
|
|
*
|
|
* This gives about 1M of write buffer for memory maps on a
|
|
* machine with 1G and 10% dirty_ratio, which should be more
|
|
* than enough.
|
|
*
|
|
* Privileged users can raise it by writing to
|
|
*
|
|
* /sys/class/bdi/<bdi>/max_ratio
|
|
*/
|
|
bdi_set_max_ratio(sb->s_bdi, 1);
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct fuse_dev *fuse_dev_alloc(void)
|
|
{
|
|
struct fuse_dev *fud;
|
|
struct list_head *pq;
|
|
|
|
fud = kzalloc(sizeof(struct fuse_dev), GFP_KERNEL);
|
|
if (!fud)
|
|
return NULL;
|
|
|
|
pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL);
|
|
if (!pq) {
|
|
kfree(fud);
|
|
return NULL;
|
|
}
|
|
|
|
fud->pq.processing = pq;
|
|
fuse_pqueue_init(&fud->pq);
|
|
|
|
return fud;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_dev_alloc);
|
|
|
|
void fuse_dev_install(struct fuse_dev *fud, struct fuse_conn *fc)
|
|
{
|
|
fud->fc = fuse_conn_get(fc);
|
|
spin_lock(&fc->lock);
|
|
list_add_tail(&fud->entry, &fc->devices);
|
|
spin_unlock(&fc->lock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_dev_install);
|
|
|
|
struct fuse_dev *fuse_dev_alloc_install(struct fuse_conn *fc)
|
|
{
|
|
struct fuse_dev *fud;
|
|
|
|
fud = fuse_dev_alloc();
|
|
if (!fud)
|
|
return NULL;
|
|
|
|
fuse_dev_install(fud, fc);
|
|
return fud;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_dev_alloc_install);
|
|
|
|
void fuse_dev_free(struct fuse_dev *fud)
|
|
{
|
|
struct fuse_conn *fc = fud->fc;
|
|
|
|
if (fc) {
|
|
spin_lock(&fc->lock);
|
|
list_del(&fud->entry);
|
|
spin_unlock(&fc->lock);
|
|
|
|
fuse_conn_put(fc);
|
|
}
|
|
kfree(fud->pq.processing);
|
|
kfree(fud);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_dev_free);
|
|
|
|
int fuse_fill_super_common(struct super_block *sb, struct fuse_fs_context *ctx)
|
|
{
|
|
struct fuse_dev *fud;
|
|
struct fuse_conn *fc = get_fuse_conn_super(sb);
|
|
struct inode *root;
|
|
struct dentry *root_dentry;
|
|
int err;
|
|
|
|
err = -EINVAL;
|
|
if (sb->s_flags & SB_MANDLOCK)
|
|
goto err;
|
|
|
|
sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
|
|
|
|
if (ctx->is_bdev) {
|
|
#ifdef CONFIG_BLOCK
|
|
err = -EINVAL;
|
|
if (!sb_set_blocksize(sb, ctx->blksize))
|
|
goto err;
|
|
#endif
|
|
} else {
|
|
sb->s_blocksize = PAGE_SIZE;
|
|
sb->s_blocksize_bits = PAGE_SHIFT;
|
|
}
|
|
|
|
sb->s_subtype = ctx->subtype;
|
|
ctx->subtype = NULL;
|
|
sb->s_magic = FUSE_SUPER_MAGIC;
|
|
sb->s_op = &fuse_super_operations;
|
|
sb->s_xattr = fuse_xattr_handlers;
|
|
sb->s_maxbytes = MAX_LFS_FILESIZE;
|
|
sb->s_time_gran = 1;
|
|
sb->s_export_op = &fuse_export_operations;
|
|
sb->s_iflags |= SB_I_IMA_UNVERIFIABLE_SIGNATURE;
|
|
if (sb->s_user_ns != &init_user_ns)
|
|
sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER;
|
|
|
|
/*
|
|
* If we are not in the initial user namespace posix
|
|
* acls must be translated.
|
|
*/
|
|
if (sb->s_user_ns != &init_user_ns)
|
|
sb->s_xattr = fuse_no_acl_xattr_handlers;
|
|
|
|
fud = fuse_dev_alloc_install(fc);
|
|
if (!fud)
|
|
goto err;
|
|
|
|
fc->dev = sb->s_dev;
|
|
fc->sb = sb;
|
|
err = fuse_bdi_init(fc, sb);
|
|
if (err)
|
|
goto err_dev_free;
|
|
|
|
/* Handle umasking inside the fuse code */
|
|
if (sb->s_flags & SB_POSIXACL)
|
|
fc->dont_mask = 1;
|
|
sb->s_flags |= SB_POSIXACL;
|
|
|
|
fc->default_permissions = ctx->default_permissions;
|
|
fc->allow_other = ctx->allow_other;
|
|
fc->user_id = ctx->user_id;
|
|
fc->group_id = ctx->group_id;
|
|
fc->max_read = max_t(unsigned, 4096, ctx->max_read);
|
|
fc->destroy = ctx->destroy;
|
|
fc->no_control = ctx->no_control;
|
|
fc->no_force_umount = ctx->no_force_umount;
|
|
fc->no_mount_options = ctx->no_mount_options;
|
|
|
|
err = -ENOMEM;
|
|
root = fuse_get_root_inode(sb, ctx->rootmode);
|
|
sb->s_d_op = &fuse_root_dentry_operations;
|
|
root_dentry = d_make_root(root);
|
|
if (!root_dentry)
|
|
goto err_dev_free;
|
|
/* Root dentry doesn't have .d_revalidate */
|
|
sb->s_d_op = &fuse_dentry_operations;
|
|
|
|
mutex_lock(&fuse_mutex);
|
|
err = -EINVAL;
|
|
if (*ctx->fudptr)
|
|
goto err_unlock;
|
|
|
|
err = fuse_ctl_add_conn(fc);
|
|
if (err)
|
|
goto err_unlock;
|
|
|
|
list_add_tail(&fc->entry, &fuse_conn_list);
|
|
sb->s_root = root_dentry;
|
|
*ctx->fudptr = fud;
|
|
mutex_unlock(&fuse_mutex);
|
|
return 0;
|
|
|
|
err_unlock:
|
|
mutex_unlock(&fuse_mutex);
|
|
dput(root_dentry);
|
|
err_dev_free:
|
|
fuse_dev_free(fud);
|
|
err:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_fill_super_common);
|
|
|
|
static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc)
|
|
{
|
|
struct fuse_fs_context *ctx = fsc->fs_private;
|
|
struct file *file;
|
|
int err;
|
|
struct fuse_conn *fc;
|
|
|
|
err = -EINVAL;
|
|
file = fget(ctx->fd);
|
|
if (!file)
|
|
goto err;
|
|
|
|
/*
|
|
* Require mount to happen from the same user namespace which
|
|
* opened /dev/fuse to prevent potential attacks.
|
|
*/
|
|
if ((file->f_op != &fuse_dev_operations) ||
|
|
(file->f_cred->user_ns != sb->s_user_ns))
|
|
goto err_fput;
|
|
ctx->fudptr = &file->private_data;
|
|
|
|
fc = kmalloc(sizeof(*fc), GFP_KERNEL);
|
|
err = -ENOMEM;
|
|
if (!fc)
|
|
goto err_fput;
|
|
|
|
fuse_conn_init(fc, sb->s_user_ns, &fuse_dev_fiq_ops, NULL);
|
|
fc->release = fuse_free_conn;
|
|
sb->s_fs_info = fc;
|
|
|
|
err = fuse_fill_super_common(sb, ctx);
|
|
if (err)
|
|
goto err_put_conn;
|
|
/*
|
|
* 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(get_fuse_conn_super(sb));
|
|
return 0;
|
|
|
|
err_put_conn:
|
|
fuse_conn_put(fc);
|
|
sb->s_fs_info = NULL;
|
|
err_fput:
|
|
fput(file);
|
|
err:
|
|
return err;
|
|
}
|
|
|
|
static int fuse_get_tree(struct fs_context *fc)
|
|
{
|
|
struct fuse_fs_context *ctx = fc->fs_private;
|
|
|
|
if (!ctx->fd_present || !ctx->rootmode_present ||
|
|
!ctx->user_id_present || !ctx->group_id_present)
|
|
return -EINVAL;
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
if (ctx->is_bdev)
|
|
return get_tree_bdev(fc, fuse_fill_super);
|
|
#endif
|
|
|
|
return get_tree_nodev(fc, fuse_fill_super);
|
|
}
|
|
|
|
static const struct fs_context_operations fuse_context_ops = {
|
|
.free = fuse_free_fc,
|
|
.parse_param = fuse_parse_param,
|
|
.get_tree = fuse_get_tree,
|
|
};
|
|
|
|
/*
|
|
* Set up the filesystem mount context.
|
|
*/
|
|
static int fuse_init_fs_context(struct fs_context *fc)
|
|
{
|
|
struct fuse_fs_context *ctx;
|
|
|
|
ctx = kzalloc(sizeof(struct fuse_fs_context), GFP_KERNEL);
|
|
if (!ctx)
|
|
return -ENOMEM;
|
|
|
|
ctx->max_read = ~0;
|
|
ctx->blksize = FUSE_DEFAULT_BLKSIZE;
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
if (fc->fs_type == &fuseblk_fs_type) {
|
|
ctx->is_bdev = true;
|
|
ctx->destroy = true;
|
|
}
|
|
#endif
|
|
|
|
fc->fs_private = ctx;
|
|
fc->ops = &fuse_context_ops;
|
|
return 0;
|
|
}
|
|
|
|
static void fuse_sb_destroy(struct super_block *sb)
|
|
{
|
|
struct fuse_conn *fc = get_fuse_conn_super(sb);
|
|
|
|
if (fc) {
|
|
if (fc->destroy)
|
|
fuse_send_destroy(fc);
|
|
|
|
fuse_abort_conn(fc);
|
|
fuse_wait_aborted(fc);
|
|
|
|
down_write(&fc->killsb);
|
|
fc->sb = NULL;
|
|
up_write(&fc->killsb);
|
|
}
|
|
}
|
|
|
|
void fuse_kill_sb_anon(struct super_block *sb)
|
|
{
|
|
fuse_sb_destroy(sb);
|
|
kill_anon_super(sb);
|
|
}
|
|
EXPORT_SYMBOL_GPL(fuse_kill_sb_anon);
|
|
|
|
static struct file_system_type fuse_fs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = "fuse",
|
|
.fs_flags = FS_HAS_SUBTYPE | FS_USERNS_MOUNT,
|
|
.init_fs_context = fuse_init_fs_context,
|
|
.parameters = &fuse_fs_parameters,
|
|
.kill_sb = fuse_kill_sb_anon,
|
|
};
|
|
MODULE_ALIAS_FS("fuse");
|
|
|
|
#ifdef CONFIG_BLOCK
|
|
static void fuse_kill_sb_blk(struct super_block *sb)
|
|
{
|
|
fuse_sb_destroy(sb);
|
|
kill_block_super(sb);
|
|
}
|
|
|
|
static struct file_system_type fuseblk_fs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = "fuseblk",
|
|
.init_fs_context = fuse_init_fs_context,
|
|
.parameters = &fuse_fs_parameters,
|
|
.kill_sb = fuse_kill_sb_blk,
|
|
.fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
|
|
};
|
|
MODULE_ALIAS_FS("fuseblk");
|
|
|
|
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(void *foo)
|
|
{
|
|
struct inode *inode = foo;
|
|
|
|
inode_init_once(inode);
|
|
}
|
|
|
|
static int __init fuse_fs_init(void)
|
|
{
|
|
int err;
|
|
|
|
fuse_inode_cachep = kmem_cache_create("fuse_inode",
|
|
sizeof(struct fuse_inode), 0,
|
|
SLAB_HWCACHE_ALIGN|SLAB_ACCOUNT|SLAB_RECLAIM_ACCOUNT,
|
|
fuse_inode_init_once);
|
|
err = -ENOMEM;
|
|
if (!fuse_inode_cachep)
|
|
goto out;
|
|
|
|
err = register_fuseblk();
|
|
if (err)
|
|
goto out2;
|
|
|
|
err = register_filesystem(&fuse_fs_type);
|
|
if (err)
|
|
goto out3;
|
|
|
|
return 0;
|
|
|
|
out3:
|
|
unregister_fuseblk();
|
|
out2:
|
|
kmem_cache_destroy(fuse_inode_cachep);
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void fuse_fs_cleanup(void)
|
|
{
|
|
unregister_filesystem(&fuse_fs_type);
|
|
unregister_fuseblk();
|
|
|
|
/*
|
|
* Make sure all delayed rcu free inodes are flushed before we
|
|
* destroy cache.
|
|
*/
|
|
rcu_barrier();
|
|
kmem_cache_destroy(fuse_inode_cachep);
|
|
}
|
|
|
|
static struct kobject *fuse_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;
|
|
}
|
|
|
|
err = sysfs_create_mount_point(fuse_kobj, "connections");
|
|
if (err)
|
|
goto out_fuse_unregister;
|
|
|
|
return 0;
|
|
|
|
out_fuse_unregister:
|
|
kobject_put(fuse_kobj);
|
|
out_err:
|
|
return err;
|
|
}
|
|
|
|
static void fuse_sysfs_cleanup(void)
|
|
{
|
|
sysfs_remove_mount_point(fuse_kobj, "connections");
|
|
kobject_put(fuse_kobj);
|
|
}
|
|
|
|
static int __init fuse_init(void)
|
|
{
|
|
int res;
|
|
|
|
pr_info("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;
|
|
|
|
sanitize_global_limit(&max_user_bgreq);
|
|
sanitize_global_limit(&max_user_congthresh);
|
|
|
|
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)
|
|
{
|
|
pr_debug("exit\n");
|
|
|
|
fuse_ctl_cleanup();
|
|
fuse_sysfs_cleanup();
|
|
fuse_fs_cleanup();
|
|
fuse_dev_cleanup();
|
|
}
|
|
|
|
module_init(fuse_init);
|
|
module_exit(fuse_exit);
|