diff options
Diffstat (limited to 'libbcachefs/fs-ioctl.c')
| -rw-r--r-- | libbcachefs/fs-ioctl.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/libbcachefs/fs-ioctl.c b/libbcachefs/fs-ioctl.c new file mode 100644 index 00000000..bd915fec --- /dev/null +++ b/libbcachefs/fs-ioctl.c @@ -0,0 +1,254 @@ +#ifndef NO_BCACHEFS_FS + +#include "bcachefs.h" +#include "chardev.h" +#include "fs.h" +#include "fs-ioctl.h" + +#include <linux/compat.h> +#include <linux/mount.h> + +#define FS_IOC_GOINGDOWN _IOR('X', 125, __u32) + +/* Inode flags: */ + +/* bcachefs inode flags -> vfs inode flags: */ +static const unsigned bch_flags_to_vfs[] = { + [__BCH_INODE_SYNC] = S_SYNC, + [__BCH_INODE_IMMUTABLE] = S_IMMUTABLE, + [__BCH_INODE_APPEND] = S_APPEND, + [__BCH_INODE_NOATIME] = S_NOATIME, +}; + +/* bcachefs inode flags -> FS_IOC_GETFLAGS: */ +static const unsigned bch_flags_to_uflags[] = { + [__BCH_INODE_SYNC] = FS_SYNC_FL, + [__BCH_INODE_IMMUTABLE] = FS_IMMUTABLE_FL, + [__BCH_INODE_APPEND] = FS_APPEND_FL, + [__BCH_INODE_NODUMP] = FS_NODUMP_FL, + [__BCH_INODE_NOATIME] = FS_NOATIME_FL, +}; + +/* bcachefs inode flags -> FS_IOC_FSGETXATTR: */ +static const unsigned bch_flags_to_xflags[] = { + [__BCH_INODE_SYNC] = FS_XFLAG_SYNC, + [__BCH_INODE_IMMUTABLE] = FS_XFLAG_IMMUTABLE, + [__BCH_INODE_APPEND] = FS_XFLAG_APPEND, + [__BCH_INODE_NODUMP] = FS_XFLAG_NODUMP, + [__BCH_INODE_NOATIME] = FS_XFLAG_NOATIME, + //[__BCH_INODE_PROJINHERIT] = FS_XFLAG_PROJINHERIT; +}; + +#define map_flags(_map, _in) \ +({ \ + unsigned _i, _out = 0; \ + \ + for (_i = 0; _i < ARRAY_SIZE(_map); _i++) \ + if ((_in) & (1 << _i)) \ + (_out) |= _map[_i]; \ + (_out); \ +}) + +#define map_flags_rev(_map, _in) \ +({ \ + unsigned _i, _out = 0; \ + \ + for (_i = 0; _i < ARRAY_SIZE(_map); _i++) \ + if ((_in) & _map[_i]) { \ + (_out) |= 1 << _i; \ + (_in) &= ~_map[_i]; \ + } \ + (_out); \ +}) + +#define set_flags(_map, _in, _out) \ +do { \ + unsigned _i; \ + \ + for (_i = 0; _i < ARRAY_SIZE(_map); _i++) \ + if ((_in) & (1 << _i)) \ + (_out) |= _map[_i]; \ + else \ + (_out) &= ~_map[_i]; \ +} while (0) + +/* Set VFS inode flags from bcachefs inode: */ +void bch2_inode_flags_to_vfs(struct bch_inode_info *inode) +{ + set_flags(bch_flags_to_vfs, inode->ei_flags, inode->v.i_flags); +} + +static int bch2_inode_flags_set(struct bch_inode_info *inode, + struct bch_inode_unpacked *bi, + void *p) +{ + /* + * We're relying on btree locking here for exclusion with other ioctl + * calls - use the flags in the btree (@bi), not inode->i_flags: + */ + unsigned newflags = *((unsigned *) p); + unsigned oldflags = bi->bi_flags; + + if (((newflags ^ oldflags) & (BCH_INODE_APPEND|BCH_INODE_IMMUTABLE)) && + !capable(CAP_LINUX_IMMUTABLE)) + return -EPERM; + + if (!S_ISREG(inode->v.i_mode) && + !S_ISDIR(inode->v.i_mode) && + (newflags & (BCH_INODE_NODUMP|BCH_INODE_NOATIME)) != newflags) + return -EINVAL; + + bi->bi_flags = newflags; + inode->v.i_ctime = current_fs_time(inode->v.i_sb); + return 0; +} + +static int bch2_ioc_getflags(struct bch_inode_info *inode, int __user *arg) +{ + unsigned flags = map_flags(bch_flags_to_uflags, inode->ei_flags); + + return put_user(flags, arg); +} + +static int bch2_ioc_setflags(struct bch_fs *c, + struct file *file, + struct bch_inode_info *inode, + void __user *arg) +{ + unsigned flags, uflags; + int ret; + + if (get_user(uflags, (int __user *) arg)) + return -EFAULT; + + flags = map_flags_rev(bch_flags_to_uflags, uflags); + if (uflags) + return -EOPNOTSUPP; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + inode_lock(&inode->v); + if (!inode_owner_or_capable(&inode->v)) { + ret = -EACCES; + goto setflags_out; + } + + mutex_lock(&inode->ei_update_lock); + ret = __bch2_write_inode(c, inode, bch2_inode_flags_set, &flags); + + if (!ret) + bch2_inode_flags_to_vfs(inode); + mutex_unlock(&inode->ei_update_lock); + +setflags_out: + inode_unlock(&inode->v); + mnt_drop_write_file(file); + return ret; +} + +static int bch2_ioc_fsgetxattr(struct bch_inode_info *inode, + struct fsxattr __user *arg) +{ + struct fsxattr fa = { 0 }; + + fa.fsx_xflags = map_flags(bch_flags_to_xflags, inode->ei_flags); + + return copy_to_user(arg, &fa, sizeof(fa)); +} + +static int bch2_ioc_fssetxattr(struct bch_fs *c, + struct file *file, + struct bch_inode_info *inode, + struct fsxattr __user *arg) +{ + struct fsxattr fa; + unsigned flags; + int ret; + + if (copy_from_user(&fa, arg, sizeof(fa))) + return -EFAULT; + + flags = map_flags_rev(bch_flags_to_xflags, fa.fsx_xflags); + if (fa.fsx_xflags) + return -EOPNOTSUPP; + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + inode_lock(&inode->v); + if (!inode_owner_or_capable(&inode->v)) { + ret = -EACCES; + goto err; + } + + mutex_lock(&inode->ei_update_lock); + ret = __bch2_write_inode(c, inode, bch2_inode_flags_set, &flags); + if (!ret) + bch2_inode_flags_to_vfs(inode); + mutex_unlock(&inode->ei_update_lock); +err: + inode_unlock(&inode->v); + mnt_drop_write_file(file); + return ret; +} + +long bch2_fs_file_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + struct bch_inode_info *inode = file_bch_inode(file); + struct super_block *sb = inode->v.i_sb; + struct bch_fs *c = sb->s_fs_info; + + switch (cmd) { + case FS_IOC_GETFLAGS: + return bch2_ioc_getflags(inode, (int __user *) arg); + + case FS_IOC_SETFLAGS: + return bch2_ioc_setflags(c, file, inode, (int __user *) arg); + + case FS_IOC_FSGETXATTR: + return bch2_ioc_fsgetxattr(inode, (void __user *) arg); + case FS_IOC_FSSETXATTR: + return bch2_ioc_fssetxattr(c, file, inode, (void __user *) arg); + + case FS_IOC_GETVERSION: + return -ENOTTY; + case FS_IOC_SETVERSION: + return -ENOTTY; + + case FS_IOC_GOINGDOWN: + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + down_write(&sb->s_umount); + sb->s_flags |= MS_RDONLY; + bch2_fs_emergency_read_only(c); + up_write(&sb->s_umount); + return 0; + + default: + return bch2_fs_ioctl(c, cmd, (void __user *) arg); + } +} + +#ifdef CONFIG_COMPAT +long bch2_compat_fs_ioctl(struct file *file, unsigned cmd, unsigned long arg) +{ + /* These are just misnamed, they actually get/put from/to user an int */ + switch (cmd) { + case FS_IOC_GETFLAGS: + cmd = FS_IOC_GETFLAGS; + break; + case FS_IOC32_SETFLAGS: + cmd = FS_IOC_SETFLAGS; + break; + default: + return -ENOIOCTLCMD; + } + return bch2_fs_file_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); +} +#endif + +#endif /* NO_BCACHEFS_FS */ |