| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Super block/filesystem wide operations |
| * |
| * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and |
| * Michael Callahan <callahan@maths.ox.ac.uk> |
| * |
| * Rewritten for Linux 2.1. Peter Braam <braam@cs.cmu.edu> |
| * Copyright (C) Carnegie Mellon University |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/string.h> |
| #include <linux/stat.h> |
| #include <linux/errno.h> |
| #include <linux/unistd.h> |
| #include <linux/mutex.h> |
| #include <linux/spinlock.h> |
| #include <linux/file.h> |
| #include <linux/vfs.h> |
| #include <linux/slab.h> |
| #include <linux/pid_namespace.h> |
| #include <linux/uaccess.h> |
| #include <linux/fs.h> |
| #include <linux/fs_context.h> |
| #include <linux/fs_parser.h> |
| #include <linux/vmalloc.h> |
| |
| #include <linux/coda.h> |
| #include "coda_psdev.h" |
| #include "coda_linux.h" |
| #include "coda_cache.h" |
| |
| #include "coda_int.h" |
| |
| /* VFS super_block ops */ |
| static void coda_evict_inode(struct inode *); |
| static void coda_put_super(struct super_block *); |
| static int coda_statfs(struct dentry *dentry, struct kstatfs *buf); |
| |
| static struct kmem_cache * coda_inode_cachep; |
| |
| static struct inode *coda_alloc_inode(struct super_block *sb) |
| { |
| struct coda_inode_info *ei; |
| ei = alloc_inode_sb(sb, coda_inode_cachep, GFP_KERNEL); |
| if (!ei) |
| return NULL; |
| memset(&ei->c_fid, 0, sizeof(struct CodaFid)); |
| ei->c_flags = 0; |
| ei->c_uid = GLOBAL_ROOT_UID; |
| ei->c_cached_perm = 0; |
| spin_lock_init(&ei->c_lock); |
| return &ei->vfs_inode; |
| } |
| |
| static void coda_free_inode(struct inode *inode) |
| { |
| kmem_cache_free(coda_inode_cachep, ITOC(inode)); |
| } |
| |
| static void init_once(void *foo) |
| { |
| struct coda_inode_info *ei = (struct coda_inode_info *) foo; |
| |
| inode_init_once(&ei->vfs_inode); |
| } |
| |
| int __init coda_init_inodecache(void) |
| { |
| coda_inode_cachep = kmem_cache_create("coda_inode_cache", |
| sizeof(struct coda_inode_info), 0, |
| SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD| |
| SLAB_ACCOUNT, init_once); |
| if (coda_inode_cachep == NULL) |
| return -ENOMEM; |
| return 0; |
| } |
| |
| void coda_destroy_inodecache(void) |
| { |
| /* |
| * Make sure all delayed rcu free inodes are flushed before we |
| * destroy cache. |
| */ |
| rcu_barrier(); |
| kmem_cache_destroy(coda_inode_cachep); |
| } |
| |
| static int coda_reconfigure(struct fs_context *fc) |
| { |
| sync_filesystem(fc->root->d_sb); |
| fc->sb_flags |= SB_NOATIME; |
| return 0; |
| } |
| |
| /* exported operations */ |
| static const struct super_operations coda_super_operations = |
| { |
| .alloc_inode = coda_alloc_inode, |
| .free_inode = coda_free_inode, |
| .evict_inode = coda_evict_inode, |
| .put_super = coda_put_super, |
| .statfs = coda_statfs, |
| }; |
| |
| struct coda_fs_context { |
| int idx; |
| }; |
| |
| enum { |
| Opt_fd, |
| }; |
| |
| static const struct fs_parameter_spec coda_param_specs[] = { |
| fsparam_fd ("fd", Opt_fd), |
| {} |
| }; |
| |
| static int coda_parse_fd(struct fs_context *fc, int fd) |
| { |
| struct coda_fs_context *ctx = fc->fs_private; |
| struct fd f; |
| struct inode *inode; |
| int idx; |
| |
| f = fdget(fd); |
| if (!f.file) |
| return -EBADF; |
| inode = file_inode(f.file); |
| if (!S_ISCHR(inode->i_mode) || imajor(inode) != CODA_PSDEV_MAJOR) { |
| fdput(f); |
| return invalf(fc, "code: Not coda psdev"); |
| } |
| |
| idx = iminor(inode); |
| fdput(f); |
| |
| if (idx < 0 || idx >= MAX_CODADEVS) |
| return invalf(fc, "coda: Bad minor number"); |
| ctx->idx = idx; |
| return 0; |
| } |
| |
| static int coda_parse_param(struct fs_context *fc, struct fs_parameter *param) |
| { |
| struct fs_parse_result result; |
| int opt; |
| |
| opt = fs_parse(fc, coda_param_specs, param, &result); |
| if (opt < 0) |
| return opt; |
| |
| switch (opt) { |
| case Opt_fd: |
| return coda_parse_fd(fc, result.uint_32); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Parse coda's binary mount data form. We ignore any errors and go with index |
| * 0 if we get one for backward compatibility. |
| */ |
| static int coda_parse_monolithic(struct fs_context *fc, void *_data) |
| { |
| struct coda_mount_data *data = _data; |
| |
| if (!data) |
| return invalf(fc, "coda: Bad mount data"); |
| |
| if (data->version != CODA_MOUNT_VERSION) |
| return invalf(fc, "coda: Bad mount version"); |
| |
| coda_parse_fd(fc, data->fd); |
| return 0; |
| } |
| |
| static int coda_fill_super(struct super_block *sb, struct fs_context *fc) |
| { |
| struct coda_fs_context *ctx = fc->fs_private; |
| struct inode *root = NULL; |
| struct venus_comm *vc; |
| struct CodaFid fid; |
| int error; |
| |
| infof(fc, "coda: device index: %i\n", ctx->idx); |
| |
| vc = &coda_comms[ctx->idx]; |
| mutex_lock(&vc->vc_mutex); |
| |
| if (!vc->vc_inuse) { |
| errorf(fc, "coda: No pseudo device"); |
| error = -EINVAL; |
| goto unlock_out; |
| } |
| |
| if (vc->vc_sb) { |
| errorf(fc, "coda: Device already mounted"); |
| error = -EBUSY; |
| goto unlock_out; |
| } |
| |
| vc->vc_sb = sb; |
| mutex_unlock(&vc->vc_mutex); |
| |
| sb->s_fs_info = vc; |
| sb->s_flags |= SB_NOATIME; |
| sb->s_blocksize = 4096; /* XXXXX what do we put here?? */ |
| sb->s_blocksize_bits = 12; |
| sb->s_magic = CODA_SUPER_MAGIC; |
| sb->s_op = &coda_super_operations; |
| sb->s_d_op = &coda_dentry_operations; |
| sb->s_time_gran = 1; |
| sb->s_time_min = S64_MIN; |
| sb->s_time_max = S64_MAX; |
| |
| error = super_setup_bdi(sb); |
| if (error) |
| goto error; |
| |
| /* get root fid from Venus: this needs the root inode */ |
| error = venus_rootfid(sb, &fid); |
| if ( error ) { |
| pr_warn("%s: coda_get_rootfid failed with %d\n", |
| __func__, error); |
| goto error; |
| } |
| pr_info("%s: rootfid is %s\n", __func__, coda_f2s(&fid)); |
| |
| /* make root inode */ |
| root = coda_cnode_make(&fid, sb); |
| if (IS_ERR(root)) { |
| error = PTR_ERR(root); |
| pr_warn("Failure of coda_cnode_make for root: error %d\n", |
| error); |
| goto error; |
| } |
| |
| pr_info("%s: rootinode is %ld dev %s\n", |
| __func__, root->i_ino, root->i_sb->s_id); |
| sb->s_root = d_make_root(root); |
| if (!sb->s_root) { |
| error = -EINVAL; |
| goto error; |
| } |
| return 0; |
| |
| error: |
| mutex_lock(&vc->vc_mutex); |
| vc->vc_sb = NULL; |
| sb->s_fs_info = NULL; |
| unlock_out: |
| mutex_unlock(&vc->vc_mutex); |
| return error; |
| } |
| |
| static void coda_put_super(struct super_block *sb) |
| { |
| struct venus_comm *vcp = coda_vcp(sb); |
| mutex_lock(&vcp->vc_mutex); |
| vcp->vc_sb = NULL; |
| sb->s_fs_info = NULL; |
| mutex_unlock(&vcp->vc_mutex); |
| mutex_destroy(&vcp->vc_mutex); |
| |
| pr_info("Bye bye.\n"); |
| } |
| |
| static void coda_evict_inode(struct inode *inode) |
| { |
| truncate_inode_pages_final(&inode->i_data); |
| clear_inode(inode); |
| coda_cache_clear_inode(inode); |
| } |
| |
| int coda_getattr(struct mnt_idmap *idmap, const struct path *path, |
| struct kstat *stat, u32 request_mask, unsigned int flags) |
| { |
| int err = coda_revalidate_inode(d_inode(path->dentry)); |
| if (!err) |
| generic_fillattr(&nop_mnt_idmap, request_mask, |
| d_inode(path->dentry), stat); |
| return err; |
| } |
| |
| int coda_setattr(struct mnt_idmap *idmap, struct dentry *de, |
| struct iattr *iattr) |
| { |
| struct inode *inode = d_inode(de); |
| struct coda_vattr vattr; |
| int error; |
| |
| memset(&vattr, 0, sizeof(vattr)); |
| |
| inode_set_ctime_current(inode); |
| coda_iattr_to_vattr(iattr, &vattr); |
| vattr.va_type = C_VNON; /* cannot set type */ |
| |
| /* Venus is responsible for truncating the container-file!!! */ |
| error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr); |
| |
| if (!error) { |
| coda_vattr_to_iattr(inode, &vattr); |
| coda_cache_clear_inode(inode); |
| } |
| return error; |
| } |
| |
| const struct inode_operations coda_file_inode_operations = { |
| .permission = coda_permission, |
| .getattr = coda_getattr, |
| .setattr = coda_setattr, |
| }; |
| |
| static int coda_statfs(struct dentry *dentry, struct kstatfs *buf) |
| { |
| int error; |
| |
| error = venus_statfs(dentry, buf); |
| |
| if (error) { |
| /* fake something like AFS does */ |
| buf->f_blocks = 9000000; |
| buf->f_bfree = 9000000; |
| buf->f_bavail = 9000000; |
| buf->f_files = 9000000; |
| buf->f_ffree = 9000000; |
| } |
| |
| /* and fill in the rest */ |
| buf->f_type = CODA_SUPER_MAGIC; |
| buf->f_bsize = 4096; |
| buf->f_namelen = CODA_MAXNAMLEN; |
| |
| return 0; |
| } |
| |
| static int coda_get_tree(struct fs_context *fc) |
| { |
| if (task_active_pid_ns(current) != &init_pid_ns) |
| return -EINVAL; |
| |
| return get_tree_nodev(fc, coda_fill_super); |
| } |
| |
| static void coda_free_fc(struct fs_context *fc) |
| { |
| kfree(fc->fs_private); |
| } |
| |
| static const struct fs_context_operations coda_context_ops = { |
| .free = coda_free_fc, |
| .parse_param = coda_parse_param, |
| .parse_monolithic = coda_parse_monolithic, |
| .get_tree = coda_get_tree, |
| .reconfigure = coda_reconfigure, |
| }; |
| |
| static int coda_init_fs_context(struct fs_context *fc) |
| { |
| struct coda_fs_context *ctx; |
| |
| ctx = kzalloc(sizeof(struct coda_fs_context), GFP_KERNEL); |
| if (!ctx) |
| return -ENOMEM; |
| |
| fc->fs_private = ctx; |
| fc->ops = &coda_context_ops; |
| return 0; |
| } |
| |
| struct file_system_type coda_fs_type = { |
| .owner = THIS_MODULE, |
| .name = "coda", |
| .init_fs_context = coda_init_fs_context, |
| .parameters = coda_param_specs, |
| .kill_sb = kill_anon_super, |
| .fs_flags = FS_BINARY_MOUNTDATA, |
| }; |
| MODULE_ALIAS_FS("coda"); |
| |