diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/fuse/inode.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/fuse/inode.c | 1267 |
1 files changed, 0 insertions, 1267 deletions
diff --git a/ANDROID_3.4.5/fs/fuse/inode.c b/ANDROID_3.4.5/fs/fuse/inode.c deleted file mode 100644 index a59cf5e6..00000000 --- a/ANDROID_3.4.5/fs/fuse/inode.c +++ /dev/null @@ -1,1267 +0,0 @@ -/* - FUSE: Filesystem in Userspace - Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> - - This program can be distributed under the terms of the GNU GPL. - See the file COPYING. -*/ - -#include "fuse_i.h" - -#include <linux/pagemap.h> -#include <linux/slab.h> -#include <linux/file.h> -#include <linux/seq_file.h> -#include <linux/init.h> -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/parser.h> -#include <linux/statfs.h> -#include <linux/random.h> -#include <linux/sched.h> -#include <linux/exportfs.h> - -MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>"); -MODULE_DESCRIPTION("Filesystem in Userspace"); -MODULE_LICENSE("GPL"); - -static struct kmem_cache *fuse_inode_cachep; -struct list_head fuse_conn_list; -DEFINE_MUTEX(fuse_mutex); - -static int set_global_limit(const char *val, struct kernel_param *kp); - -unsigned max_user_bgreq; -module_param_call(max_user_bgreq, set_global_limit, param_get_uint, - &max_user_bgreq, 0644); -__MODULE_PARM_TYPE(max_user_bgreq, "uint"); -MODULE_PARM_DESC(max_user_bgreq, - "Global limit for the maximum number of backgrounded requests an " - "unprivileged user can set"); - -unsigned max_user_congthresh; -module_param_call(max_user_congthresh, set_global_limit, param_get_uint, - &max_user_congthresh, 0644); -__MODULE_PARM_TYPE(max_user_congthresh, "uint"); -MODULE_PARM_DESC(max_user_congthresh, - "Global limit for the maximum congestion threshold an " - "unprivileged user can set"); - -#define FUSE_SUPER_MAGIC 0x65735546 - -#define FUSE_DEFAULT_BLKSIZE 512 - -/** Maximum number of outstanding background requests */ -#define FUSE_DEFAULT_MAX_BACKGROUND 12 - -/** Congestion starts at 75% of maximum */ -#define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4) - -struct fuse_mount_data { - int fd; - unsigned rootmode; - unsigned user_id; - unsigned group_id; - unsigned fd_present:1; - unsigned rootmode_present:1; - unsigned user_id_present:1; - unsigned group_id_present:1; - unsigned flags; - unsigned max_read; - unsigned blksize; -}; - -struct fuse_forget_link *fuse_alloc_forget(void) -{ - return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL); -} - -static struct inode *fuse_alloc_inode(struct super_block *sb) -{ - struct inode *inode; - struct fuse_inode *fi; - - inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL); - if (!inode) - return NULL; - - fi = get_fuse_inode(inode); - fi->i_time = 0; - fi->nodeid = 0; - fi->nlookup = 0; - fi->attr_version = 0; - fi->writectr = 0; - fi->orig_ino = 0; - INIT_LIST_HEAD(&fi->write_files); - INIT_LIST_HEAD(&fi->queued_writes); - INIT_LIST_HEAD(&fi->writepages); - init_waitqueue_head(&fi->page_waitq); - fi->forget = fuse_alloc_forget(); - if (!fi->forget) { - kmem_cache_free(fuse_inode_cachep, inode); - return NULL; - } - - return inode; -} - -static void fuse_i_callback(struct rcu_head *head) -{ - struct inode *inode = container_of(head, struct inode, i_rcu); - kmem_cache_free(fuse_inode_cachep, inode); -} - -static void fuse_destroy_inode(struct inode *inode) -{ - struct fuse_inode *fi = get_fuse_inode(inode); - BUG_ON(!list_empty(&fi->write_files)); - BUG_ON(!list_empty(&fi->queued_writes)); - kfree(fi->forget); - call_rcu(&inode->i_rcu, fuse_i_callback); -} - -static void fuse_evict_inode(struct inode *inode) -{ - truncate_inode_pages(&inode->i_data, 0); - end_writeback(inode); - if (inode->i_sb->s_flags & MS_ACTIVE) { - struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_inode *fi = get_fuse_inode(inode); - fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup); - fi->forget = NULL; - } -} - -static int fuse_remount_fs(struct super_block *sb, int *flags, char *data) -{ - if (*flags & MS_MANDLOCK) - return -EINVAL; - - return 0; -} - -/* - * ino_t is 32-bits on 32-bit arch. We have to squash the 64-bit value down - * so that it will fit. - */ -static ino_t fuse_squash_ino(u64 ino64) -{ - ino_t ino = (ino_t) ino64; - if (sizeof(ino_t) < sizeof(u64)) - ino ^= ino64 >> (sizeof(u64) - sizeof(ino_t)) * 8; - return ino; -} - -void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr, - u64 attr_valid) -{ - struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_inode *fi = get_fuse_inode(inode); - - fi->attr_version = ++fc->attr_version; - fi->i_time = attr_valid; - - inode->i_ino = fuse_squash_ino(attr->ino); - inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777); - set_nlink(inode, attr->nlink); - inode->i_uid = attr->uid; - inode->i_gid = attr->gid; - inode->i_blocks = attr->blocks; - inode->i_atime.tv_sec = attr->atime; - inode->i_atime.tv_nsec = attr->atimensec; - inode->i_mtime.tv_sec = attr->mtime; - inode->i_mtime.tv_nsec = attr->mtimensec; - inode->i_ctime.tv_sec = attr->ctime; - inode->i_ctime.tv_nsec = attr->ctimensec; - - if (attr->blksize != 0) - inode->i_blkbits = ilog2(attr->blksize); - else - inode->i_blkbits = inode->i_sb->s_blocksize_bits; - - /* - * Don't set the sticky bit in i_mode, unless we want the VFS - * to check permissions. This prevents failures due to the - * check in may_delete(). - */ - fi->orig_i_mode = inode->i_mode; - if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS)) - inode->i_mode &= ~S_ISVTX; - - fi->orig_ino = attr->ino; -} - -void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr, - u64 attr_valid, u64 attr_version) -{ - struct fuse_conn *fc = get_fuse_conn(inode); - struct fuse_inode *fi = get_fuse_inode(inode); - loff_t oldsize; - - spin_lock(&fc->lock); - if (attr_version != 0 && fi->attr_version > attr_version) { - spin_unlock(&fc->lock); - return; - } - - fuse_change_attributes_common(inode, attr, attr_valid); - - oldsize = inode->i_size; - i_size_write(inode, attr->size); - spin_unlock(&fc->lock); - - if (S_ISREG(inode->i_mode) && oldsize != attr->size) { - truncate_pagecache(inode, oldsize, attr->size); - invalidate_inode_pages2(inode->i_mapping); - } -} - -static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr) -{ - inode->i_mode = attr->mode & S_IFMT; - inode->i_size = attr->size; - if (S_ISREG(inode->i_mode)) { - fuse_init_common(inode); - fuse_init_file_inode(inode); - } else if (S_ISDIR(inode->i_mode)) - fuse_init_dir(inode); - else if (S_ISLNK(inode->i_mode)) - fuse_init_symlink(inode); - else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || - S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { - fuse_init_common(inode); - init_special_inode(inode, inode->i_mode, - new_decode_dev(attr->rdev)); - } else - BUG(); -} - -int fuse_inode_eq(struct inode *inode, void *_nodeidp) -{ - u64 nodeid = *(u64 *) _nodeidp; - if (get_node_id(inode) == nodeid) - return 1; - else - return 0; -} - -static int fuse_inode_set(struct inode *inode, void *_nodeidp) -{ - u64 nodeid = *(u64 *) _nodeidp; - get_fuse_inode(inode)->nodeid = nodeid; - return 0; -} - -struct inode *fuse_iget(struct super_block *sb, u64 nodeid, - int generation, struct fuse_attr *attr, - u64 attr_valid, u64 attr_version) -{ - struct inode *inode; - struct fuse_inode *fi; - struct fuse_conn *fc = get_fuse_conn_super(sb); - - retry: - inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid); - if (!inode) - return NULL; - - if ((inode->i_state & I_NEW)) { - inode->i_flags |= S_NOATIME|S_NOCMTIME; - inode->i_generation = generation; - inode->i_data.backing_dev_info = &fc->bdi; - fuse_init_inode(inode, attr); - unlock_new_inode(inode); - } else if ((inode->i_mode ^ attr->mode) & S_IFMT) { - /* Inode has changed type, any I/O on the old should fail */ - make_bad_inode(inode); - iput(inode); - goto retry; - } - - fi = get_fuse_inode(inode); - spin_lock(&fc->lock); - fi->nlookup++; - spin_unlock(&fc->lock); - fuse_change_attributes(inode, attr, attr_valid, attr_version); - - return inode; -} - -int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid, - loff_t offset, loff_t len) -{ - struct inode *inode; - pgoff_t pg_start; - pgoff_t pg_end; - - inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid); - if (!inode) - return -ENOENT; - - fuse_invalidate_attr(inode); - if (offset >= 0) { - pg_start = offset >> PAGE_CACHE_SHIFT; - if (len <= 0) - pg_end = -1; - else - pg_end = (offset + len - 1) >> PAGE_CACHE_SHIFT; - invalidate_inode_pages2_range(inode->i_mapping, - pg_start, pg_end); - } - iput(inode); - return 0; -} - -static void fuse_umount_begin(struct super_block *sb) -{ - fuse_abort_conn(get_fuse_conn_super(sb)); -} - -static void fuse_send_destroy(struct fuse_conn *fc) -{ - struct fuse_req *req = fc->destroy_req; - if (req && fc->conn_init) { - fc->destroy_req = NULL; - req->in.h.opcode = FUSE_DESTROY; - req->force = 1; - fuse_request_send(fc, req); - fuse_put_request(fc, req); - } -} - -static void fuse_bdi_destroy(struct fuse_conn *fc) -{ - if (fc->bdi_initialized) - bdi_destroy(&fc->bdi); -} - -void fuse_conn_kill(struct fuse_conn *fc) -{ - spin_lock(&fc->lock); - fc->connected = 0; - fc->blocked = 0; - spin_unlock(&fc->lock); - /* Flush all readers on this fs */ - kill_fasync(&fc->fasync, SIGIO, POLL_IN); - wake_up_all(&fc->waitq); - wake_up_all(&fc->blocked_waitq); - wake_up_all(&fc->reserved_req_waitq); - mutex_lock(&fuse_mutex); - list_del(&fc->entry); - fuse_ctl_remove_conn(fc); - mutex_unlock(&fuse_mutex); - fuse_bdi_destroy(fc); -} -EXPORT_SYMBOL_GPL(fuse_conn_kill); - -static void fuse_put_super(struct super_block *sb) -{ - struct fuse_conn *fc = get_fuse_conn_super(sb); - - fuse_send_destroy(fc); - fuse_conn_kill(fc); - fuse_conn_put(fc); -} - -static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr) -{ - stbuf->f_type = FUSE_SUPER_MAGIC; - stbuf->f_bsize = attr->bsize; - stbuf->f_frsize = attr->frsize; - stbuf->f_blocks = attr->blocks; - stbuf->f_bfree = attr->bfree; - stbuf->f_bavail = attr->bavail; - stbuf->f_files = attr->files; - stbuf->f_ffree = attr->ffree; - stbuf->f_namelen = attr->namelen; - /* fsid is left zero */ -} - -static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf) -{ - struct super_block *sb = dentry->d_sb; - struct fuse_conn *fc = get_fuse_conn_super(sb); - struct fuse_req *req; - struct fuse_statfs_out outarg; - int err; - - if (!fuse_allow_task(fc, current)) { - buf->f_type = FUSE_SUPER_MAGIC; - return 0; - } - - req = fuse_get_req(fc); - if (IS_ERR(req)) - return PTR_ERR(req); - - memset(&outarg, 0, sizeof(outarg)); - req->in.numargs = 0; - req->in.h.opcode = FUSE_STATFS; - req->in.h.nodeid = get_node_id(dentry->d_inode); - req->out.numargs = 1; - req->out.args[0].size = - fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg); - req->out.args[0].value = &outarg; - fuse_request_send(fc, req); - err = req->out.h.error; - if (!err) - convert_fuse_statfs(buf, &outarg.st); - fuse_put_request(fc, req); - return err; -} - -enum { - OPT_FD, - OPT_ROOTMODE, - OPT_USER_ID, - OPT_GROUP_ID, - OPT_DEFAULT_PERMISSIONS, - OPT_ALLOW_OTHER, - OPT_MAX_READ, - OPT_BLKSIZE, - OPT_ERR -}; - -static const match_table_t tokens = { - {OPT_FD, "fd=%u"}, - {OPT_ROOTMODE, "rootmode=%o"}, - {OPT_USER_ID, "user_id=%u"}, - {OPT_GROUP_ID, "group_id=%u"}, - {OPT_DEFAULT_PERMISSIONS, "default_permissions"}, - {OPT_ALLOW_OTHER, "allow_other"}, - {OPT_MAX_READ, "max_read=%u"}, - {OPT_BLKSIZE, "blksize=%u"}, - {OPT_ERR, NULL} -}; - -static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev) -{ - char *p; - memset(d, 0, sizeof(struct fuse_mount_data)); - d->max_read = ~0; - d->blksize = FUSE_DEFAULT_BLKSIZE; - - while ((p = strsep(&opt, ",")) != NULL) { - int token; - int value; - substring_t args[MAX_OPT_ARGS]; - if (!*p) - continue; - - token = match_token(p, tokens, args); - switch (token) { - case OPT_FD: - if (match_int(&args[0], &value)) - return 0; - d->fd = value; - d->fd_present = 1; - break; - - case OPT_ROOTMODE: - if (match_octal(&args[0], &value)) - return 0; - if (!fuse_valid_type(value)) - return 0; - d->rootmode = value; - d->rootmode_present = 1; - break; - - case OPT_USER_ID: - if (match_int(&args[0], &value)) - return 0; - d->user_id = value; - d->user_id_present = 1; - break; - - case OPT_GROUP_ID: - if (match_int(&args[0], &value)) - return 0; - d->group_id = value; - d->group_id_present = 1; - break; - - case OPT_DEFAULT_PERMISSIONS: - d->flags |= FUSE_DEFAULT_PERMISSIONS; - break; - - case OPT_ALLOW_OTHER: - d->flags |= FUSE_ALLOW_OTHER; - break; - - case OPT_MAX_READ: - if (match_int(&args[0], &value)) - return 0; - d->max_read = value; - break; - - case OPT_BLKSIZE: - if (!is_bdev || match_int(&args[0], &value)) - return 0; - d->blksize = value; - break; - - default: - return 0; - } - } - - if (!d->fd_present || !d->rootmode_present || - !d->user_id_present || !d->group_id_present) - return 0; - - return 1; -} - -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); - - seq_printf(m, ",user_id=%u", fc->user_id); - seq_printf(m, ",group_id=%u", fc->group_id); - if (fc->flags & FUSE_DEFAULT_PERMISSIONS) - seq_puts(m, ",default_permissions"); - if (fc->flags & FUSE_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; -} - -void fuse_conn_init(struct fuse_conn *fc) -{ - memset(fc, 0, sizeof(*fc)); - spin_lock_init(&fc->lock); - mutex_init(&fc->inst_mutex); - init_rwsem(&fc->killsb); - atomic_set(&fc->count, 1); - init_waitqueue_head(&fc->waitq); - init_waitqueue_head(&fc->blocked_waitq); - init_waitqueue_head(&fc->reserved_req_waitq); - INIT_LIST_HEAD(&fc->pending); - INIT_LIST_HEAD(&fc->processing); - INIT_LIST_HEAD(&fc->io); - INIT_LIST_HEAD(&fc->interrupts); - INIT_LIST_HEAD(&fc->bg_queue); - INIT_LIST_HEAD(&fc->entry); - fc->forget_list_tail = &fc->forget_list_head; - atomic_set(&fc->num_waiting, 0); - fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND; - fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD; - fc->khctr = 0; - fc->polled_files = RB_ROOT; - fc->reqctr = 0; - fc->blocked = 1; - fc->attr_version = 1; - get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key)); -} -EXPORT_SYMBOL_GPL(fuse_conn_init); - -void fuse_conn_put(struct fuse_conn *fc) -{ - if (atomic_dec_and_test(&fc->count)) { - if (fc->destroy_req) - fuse_request_free(fc->destroy_req); - mutex_destroy(&fc->inst_mutex); - fc->release(fc); - } -} -EXPORT_SYMBOL_GPL(fuse_conn_put); - -struct fuse_conn *fuse_conn_get(struct fuse_conn *fc) -{ - atomic_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; - struct qstr name; - - if (!fc->export_support) - goto out_err; - - name.len = 1; - name.name = "."; - 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 dentry *dentry, u32 *fh, int *max_len, - int connectable) -{ - struct inode *inode = dentry->d_inode; - bool encode_parent = connectable && !S_ISDIR(inode->i_mode); - int len = encode_parent ? 6 : 3; - u64 nodeid; - u32 generation; - - if (*max_len < len) { - *max_len = len; - return 255; - } - - nodeid = get_fuse_inode(inode)->nodeid; - generation = inode->i_generation; - - fh[0] = (u32)(nodeid >> 32); - fh[1] = (u32)(nodeid & 0xffffffff); - fh[2] = generation; - - if (encode_parent) { - struct inode *parent; - - spin_lock(&dentry->d_lock); - parent = dentry->d_parent->d_inode; - nodeid = get_fuse_inode(parent)->nodeid; - generation = parent->i_generation; - spin_unlock(&dentry->d_lock); - - fh[3] = (u32)(nodeid >> 32); - fh[4] = (u32)(nodeid & 0xffffffff); - fh[5] = generation; - } - - *max_len = len; - return encode_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 = child->d_inode; - struct fuse_conn *fc = get_fuse_conn(child_inode); - struct inode *inode; - struct dentry *parent; - struct fuse_entry_out outarg; - struct qstr name; - int err; - - if (!fc->export_support) - return ERR_PTR(-ESTALE); - - name.len = 2; - name.name = ".."; - 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, - .destroy_inode = fuse_destroy_inode, - .evict_inode = fuse_evict_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) -{ - if (*limit == 0) - *limit = ((num_physpages << PAGE_SHIFT) >> 13) / - sizeof(struct fuse_req); - - if (*limit >= 1 << 16) - *limit = (1 << 16) - 1; -} - -static int set_global_limit(const char *val, 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); - - 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; - } -} - -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; - - process_init_limits(fc, arg); - - 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->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; - } else { - ra_pages = fc->max_read / PAGE_CACHE_SIZE; - fc->no_lock = 1; - fc->no_flock = 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->max_write = max_t(unsigned, 4096, fc->max_write); - fc->conn_init = 1; - } - 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 | - FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK | - FUSE_FLOCK_LOCKS; - 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 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 */ - 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; - fuse_request_send_background(fc, req); -} - -static void fuse_free_conn(struct fuse_conn *fc) -{ - kfree(fc); -} - -static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb) -{ - int err; - - fc->bdi.name = "fuse"; - fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE; - /* fuse does it's own writeback accounting */ - fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB; - - err = bdi_init(&fc->bdi); - if (err) - return err; - - fc->bdi_initialized = 1; - - if (sb->s_bdev) { - err = bdi_register(&fc->bdi, NULL, "%u:%u-fuseblk", - MAJOR(fc->dev), MINOR(fc->dev)); - } else { - err = bdi_register_dev(&fc->bdi, fc->dev); - } - - if (err) - return err; - - /* - * 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(&fc->bdi, 1); - - return 0; -} - -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; - - err = -EINVAL; - if (sb->s_flags & MS_MANDLOCK) - goto err; - - sb->s_flags &= ~MS_NOSEC; - - if (!parse_fuse_opt((char *) data, &d, is_bdev)) - goto err; - - if (is_bdev) { -#ifdef CONFIG_BLOCK - err = -EINVAL; - if (!sb_set_blocksize(sb, d.blksize)) - goto err; -#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; - sb->s_time_gran = 1; - sb->s_export_op = &fuse_export_operations; - - file = fget(d.fd); - err = -EINVAL; - if (!file) - goto err; - - if (file->f_op != &fuse_dev_operations) - goto err_fput; - - fc = kmalloc(sizeof(*fc), GFP_KERNEL); - err = -ENOMEM; - if (!fc) - goto err_fput; - - fuse_conn_init(fc); - - fc->dev = sb->s_dev; - fc->sb = sb; - err = fuse_bdi_init(fc, sb); - if (err) - goto err_put_conn; - - sb->s_bdi = &fc->bdi; - - /* Handle umasking inside the fuse code */ - if (sb->s_flags & MS_POSIXACL) - fc->dont_mask = 1; - sb->s_flags |= MS_POSIXACL; - - fc->release = fuse_free_conn; - fc->flags = d.flags; - fc->user_id = d.user_id; - fc->group_id = d.group_id; - fc->max_read = max_t(unsigned, 4096, d.max_read); - - /* Used by get_root_inode() */ - sb->s_fs_info = fc; - - err = -ENOMEM; - root = fuse_get_root_inode(sb, d.rootmode); - root_dentry = d_make_root(root); - if (!root_dentry) - goto err_put_conn; - /* only now - we want root dentry with NULL ->d_op */ - sb->s_d_op = &fuse_dentry_operations; - - 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_free_init_req; - } - - mutex_lock(&fuse_mutex); - err = -EINVAL; - if (file->private_data) - 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; - 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); - err_free_init_req: - fuse_request_free(init_req); - err_put_root: - dput(root_dentry); - err_put_conn: - fuse_bdi_destroy(fc); - fuse_conn_put(fc); - err_fput: - fput(file); - err: - return err; -} - -static struct dentry *fuse_mount(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *raw_data) -{ - return mount_nodev(fs_type, flags, raw_data, fuse_fill_super); -} - -static void fuse_kill_sb_anon(struct super_block *sb) -{ - struct fuse_conn *fc = get_fuse_conn_super(sb); - - if (fc) { - down_write(&fc->killsb); - fc->sb = NULL; - up_write(&fc->killsb); - } - - kill_anon_super(sb); -} - -static struct file_system_type fuse_fs_type = { - .owner = THIS_MODULE, - .name = "fuse", - .fs_flags = FS_HAS_SUBTYPE, - .mount = fuse_mount, - .kill_sb = fuse_kill_sb_anon, -}; - -#ifdef CONFIG_BLOCK -static struct dentry *fuse_mount_blk(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *raw_data) -{ - return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super); -} - -static void fuse_kill_sb_blk(struct super_block *sb) -{ - struct fuse_conn *fc = get_fuse_conn_super(sb); - - if (fc) { - down_write(&fc->killsb); - fc->sb = NULL; - up_write(&fc->killsb); - } - - kill_block_super(sb); -} - -static struct file_system_type fuseblk_fs_type = { - .owner = THIS_MODULE, - .name = "fuseblk", - .mount = fuse_mount_blk, - .kill_sb = fuse_kill_sb_blk, - .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(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, - 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(); - 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(KERN_INFO "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; - - 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) -{ - 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); |