diff options
Diffstat (limited to 'fs/ioctl.c')
-rw-r--r-- | fs/ioctl.c | 92 |
1 files changed, 81 insertions, 11 deletions
diff --git a/fs/ioctl.c b/fs/ioctl.c index 43e8b2c0664..240ec63984c 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -231,7 +231,8 @@ static int ioctl_fiemap(struct file *filp, unsigned long arg) #define blk_to_logical(inode, blk) (blk << (inode)->i_blkbits) #define logical_to_blk(inode, offset) (offset >> (inode)->i_blkbits); -/* +/** + * __generic_block_fiemap - FIEMAP for block based inodes (no locking) * @inode - the inode to map * @arg - the pointer to userspace where we copy everything to * @get_block - the fs's get_block function @@ -242,11 +243,15 @@ static int ioctl_fiemap(struct file *filp, unsigned long arg) * * If it is possible to have data blocks beyond a hole past @inode->i_size, then * please do not use this function, it will stop at the first unmapped block - * beyond i_size + * beyond i_size. + * + * If you use this function directly, you need to do your own locking. Use + * generic_block_fiemap if you want the locking done for you. */ -int generic_block_fiemap(struct inode *inode, - struct fiemap_extent_info *fieinfo, u64 start, - u64 len, get_block_t *get_block) + +int __generic_block_fiemap(struct inode *inode, + struct fiemap_extent_info *fieinfo, u64 start, + u64 len, get_block_t *get_block) { struct buffer_head tmp; unsigned int start_blk; @@ -260,9 +265,6 @@ int generic_block_fiemap(struct inode *inode, start_blk = logical_to_blk(inode, start); - /* guard against change */ - mutex_lock(&inode->i_mutex); - length = (long long)min_t(u64, len, i_size_read(inode)); map_len = length; @@ -334,14 +336,36 @@ int generic_block_fiemap(struct inode *inode, cond_resched(); } while (1); - mutex_unlock(&inode->i_mutex); - /* if ret is 1 then we just hit the end of the extent array */ if (ret == 1) ret = 0; return ret; } +EXPORT_SYMBOL(__generic_block_fiemap); + +/** + * generic_block_fiemap - FIEMAP for block based inodes + * @inode: The inode to map + * @fieinfo: The mapping information + * @start: The initial block to map + * @len: The length of the extect to attempt to map + * @get_block: The block mapping function for the fs + * + * Calls __generic_block_fiemap to map the inode, after taking + * the inode's mutex lock. + */ + +int generic_block_fiemap(struct inode *inode, + struct fiemap_extent_info *fieinfo, u64 start, + u64 len, get_block_t *get_block) +{ + int ret; + mutex_lock(&inode->i_mutex); + ret = __generic_block_fiemap(inode, fieinfo, start, len, get_block); + mutex_unlock(&inode->i_mutex); + return ret; +} EXPORT_SYMBOL(generic_block_fiemap); #endif /* CONFIG_BLOCK */ @@ -415,6 +439,43 @@ static int ioctl_fioasync(unsigned int fd, struct file *filp, return error; } +static int ioctl_fsfreeze(struct file *filp) +{ + struct super_block *sb = filp->f_path.dentry->d_inode->i_sb; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* If filesystem doesn't support freeze feature, return. */ + if (sb->s_op->freeze_fs == NULL) + return -EOPNOTSUPP; + + /* If a blockdevice-backed filesystem isn't specified, return. */ + if (sb->s_bdev == NULL) + return -EINVAL; + + /* Freeze */ + sb = freeze_bdev(sb->s_bdev); + if (IS_ERR(sb)) + return PTR_ERR(sb); + return 0; +} + +static int ioctl_fsthaw(struct file *filp) +{ + struct super_block *sb = filp->f_path.dentry->d_inode->i_sb; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + /* If a blockdevice-backed filesystem isn't specified, return EINVAL. */ + if (sb->s_bdev == NULL) + return -EINVAL; + + /* Thaw */ + return thaw_bdev(sb->s_bdev, sb); +} + /* * When you add any new common ioctls to the switches above and below * please update compat_sys_ioctl() too. @@ -462,6 +523,15 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, } else error = -ENOTTY; break; + + case FIFREEZE: + error = ioctl_fsfreeze(filp); + break; + + case FITHAW: + error = ioctl_fsthaw(filp); + break; + default: if (S_ISREG(filp->f_path.dentry->d_inode->i_mode)) error = file_ioctl(filp, cmd, arg); @@ -472,7 +542,7 @@ int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd, return error; } -asmlinkage long sys_ioctl(unsigned int fd, unsigned int cmd, unsigned long arg) +SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg) { struct file *filp; int error = -EBADF; |