diff options
| -rw-r--r-- | fs/block_dev.c | 3 | ||||
| -rw-r--r-- | include/linux/fs.h | 11 | ||||
| -rw-r--r-- | mm/filemap.c | 3 | ||||
| -rw-r--r-- | mm/memory.c | 4 | ||||
| -rw-r--r-- | mm/mmap.c | 8 | ||||
| -rw-r--r-- | mm/swapfile.c | 12 |
6 files changed, 38 insertions, 3 deletions
diff --git a/fs/block_dev.c b/fs/block_dev.c index c2a85b587922..d9bab63a9b81 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1978,6 +1978,9 @@ ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from) if (bdev_read_only(I_BDEV(bd_inode))) return -EPERM; + if (IS_SWAPFILE(bd_inode)) + return -ETXTBSY; + if (!iov_iter_count(from)) return 0; diff --git a/include/linux/fs.h b/include/linux/fs.h index 56b8e358af5c..a2e3d446ba8e 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3547,4 +3547,15 @@ static inline void simple_fill_fsxattr(struct fsxattr *fa, __u32 xflags) fa->fsx_xflags = xflags; } +/* + * Flush file data before changing attributes. Caller must hold any locks + * required to prevent further writes to this file until we're done setting + * flags. + */ +static inline int inode_drain_writes(struct inode *inode) +{ + inode_dio_wait(inode); + return filemap_write_and_wait(inode->i_mapping); +} + #endif /* _LINUX_FS_H */ diff --git a/mm/filemap.c b/mm/filemap.c index d0cf700bf201..40667c2f3383 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -2988,6 +2988,9 @@ inline ssize_t generic_write_checks(struct kiocb *iocb, struct iov_iter *from) loff_t count; int ret; + if (IS_SWAPFILE(inode)) + return -ETXTBSY; + if (!iov_iter_count(from)) return 0; diff --git a/mm/memory.c b/mm/memory.c index e2bb51b6242e..b1dff75640b7 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2196,6 +2196,10 @@ static vm_fault_t do_page_mkwrite(struct vm_fault *vmf) vmf->flags = FAULT_FLAG_WRITE|FAULT_FLAG_MKWRITE; + if (vmf->vma->vm_file && + IS_SWAPFILE(vmf->vma->vm_file->f_mapping->host)) + return VM_FAULT_SIGBUS; + ret = vmf->vma->vm_ops->page_mkwrite(vmf); /* Restore original flags so that caller is not surprised */ vmf->flags = old_flags; diff --git a/mm/mmap.c b/mm/mmap.c index 7e8c3e8ae75f..6bc21fca20bc 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1483,8 +1483,12 @@ unsigned long do_mmap(struct file *file, unsigned long addr, case MAP_SHARED_VALIDATE: if (flags & ~flags_mask) return -EOPNOTSUPP; - if ((prot&PROT_WRITE) && !(file->f_mode&FMODE_WRITE)) - return -EACCES; + if (prot & PROT_WRITE) { + if (!(file->f_mode & FMODE_WRITE)) + return -EACCES; + if (IS_SWAPFILE(file->f_mapping->host)) + return -ETXTBSY; + } /* * Make sure we don't allow writing to an append-only diff --git a/mm/swapfile.c b/mm/swapfile.c index a53b7c49b40e..dab43523afdd 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3275,6 +3275,17 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (error) goto bad_swap; + /* + * Flush any pending IO and dirty mappings before we start using this + * swap device. + */ + inode->i_flags |= S_SWAPFILE; + error = inode_drain_writes(inode); + if (error) { + inode->i_flags &= ~S_SWAPFILE; + goto bad_swap; + } + mutex_lock(&swapon_mutex); prio = -1; if (swap_flags & SWAP_FLAG_PREFER) @@ -3295,7 +3306,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) atomic_inc(&proc_poll_event); wake_up_interruptible(&proc_poll_wait); - inode->i_flags |= S_SWAPFILE; error = 0; goto out; bad_swap: |