diff options
Diffstat (limited to 'fs/ext4/file.c')
| -rw-r--r-- | fs/ext4/file.c | 49 |
1 files changed, 21 insertions, 28 deletions
diff --git a/fs/ext4/file.c b/fs/ext4/file.c index c457c8517f0f..6830ea3a6c59 100644 --- a/fs/ext4/file.c +++ b/fs/ext4/file.c @@ -131,7 +131,7 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to) { struct inode *inode = file_inode(iocb->ki_filp); - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; if (!iov_iter_count(to)) @@ -153,7 +153,7 @@ static ssize_t ext4_file_splice_read(struct file *in, loff_t *ppos, { struct inode *inode = file_inode(in); - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; return filemap_splice_read(in, ppos, pipe, len, flags); } @@ -476,6 +476,11 @@ restart: * required to change security info in file_modified(), for extending * I/O, any form of non-overwrite I/O, and unaligned I/O to unwritten * extents (as partial block zeroing may be required). + * + * Note that unaligned writes are allowed under shared lock so long as + * they are pure overwrites. Otherwise, concurrent unaligned writes risk + * data corruption due to partial block zeroing in the dio layer, and so + * the I/O must occur exclusively. */ if (*ilock_shared && ((!IS_NOSEC(inode) || *extend || !overwrite || @@ -492,21 +497,12 @@ restart: /* * Now that locking is settled, determine dio flags and exclusivity - * requirements. Unaligned writes are allowed under shared lock so long - * as they are pure overwrites. Set the iomap overwrite only flag as an - * added precaution in this case. Even though this is unnecessary, we - * can detect and warn on unexpected -EAGAIN if an unsafe unaligned - * write is ever submitted. - * - * Otherwise, concurrent unaligned writes risk data corruption due to - * partial block zeroing in the dio layer, and so the I/O must occur - * exclusively. The inode lock is already held exclusive if the write is - * non-overwrite or extending, so drain all outstanding dio and set the - * force wait dio flag. + * requirements. We don't use DIO_OVERWRITE_ONLY because we enforce + * behavior already. The inode lock is already held exclusive if the + * write is non-overwrite or extending, so drain all outstanding dio and + * set the force wait dio flag. */ - if (*ilock_shared && unaligned_io) { - *dio_flags = IOMAP_DIO_OVERWRITE_ONLY; - } else if (!*ilock_shared && (unaligned_io || *extend)) { + if (!*ilock_shared && (unaligned_io || *extend)) { if (iocb->ki_flags & IOCB_NOWAIT) { ret = -EAGAIN; goto out; @@ -608,7 +604,6 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from) iomap_ops = &ext4_iomap_overwrite_ops; ret = iomap_dio_rw(iocb, from, iomap_ops, &ext4_dio_write_ops, dio_flags, NULL, 0); - WARN_ON_ONCE(ret == -EAGAIN && !(iocb->ki_flags & IOCB_NOWAIT)); if (ret == -ENOTBLK) ret = 0; @@ -709,7 +704,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct inode *inode = file_inode(iocb->ki_filp); - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; #ifdef CONFIG_FS_DAX @@ -723,8 +718,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) } #ifdef CONFIG_FS_DAX -static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, - enum page_entry_size pe_size) +static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, unsigned int order) { int error = 0; vm_fault_t result; @@ -740,7 +734,7 @@ static vm_fault_t ext4_dax_huge_fault(struct vm_fault *vmf, * read-only. * * We check for VM_SHARED rather than vmf->cow_page since the latter is - * unset for pe_size != PE_SIZE_PTE (i.e. only in do_cow_fault); for + * unset for order != 0 (i.e. only in do_cow_fault); for * other sizes, dax_iomap_fault will handle splitting / fallback so that * we eventually come back with a COW page. */ @@ -764,7 +758,7 @@ retry: } else { filemap_invalidate_lock_shared(mapping); } - result = dax_iomap_fault(vmf, pe_size, &pfn, &error, &ext4_iomap_ops); + result = dax_iomap_fault(vmf, order, &pfn, &error, &ext4_iomap_ops); if (write) { ext4_journal_stop(handle); @@ -773,7 +767,7 @@ retry: goto retry; /* Handling synchronous page fault? */ if (result & VM_FAULT_NEEDDSYNC) - result = dax_finish_sync_fault(vmf, pe_size, pfn); + result = dax_finish_sync_fault(vmf, order, pfn); filemap_invalidate_unlock_shared(mapping); sb_end_pagefault(sb); } else { @@ -785,7 +779,7 @@ retry: static vm_fault_t ext4_dax_fault(struct vm_fault *vmf) { - return ext4_dax_huge_fault(vmf, PE_SIZE_PTE); + return ext4_dax_huge_fault(vmf, 0); } static const struct vm_operations_struct ext4_dax_vm_ops = { @@ -807,10 +801,9 @@ static const struct vm_operations_struct ext4_file_vm_ops = { static int ext4_file_mmap(struct file *file, struct vm_area_struct *vma) { struct inode *inode = file->f_mapping->host; - struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); - struct dax_device *dax_dev = sbi->s_daxdev; + struct dax_device *dax_dev = EXT4_SB(inode->i_sb)->s_daxdev; - if (unlikely(ext4_forced_shutdown(sbi))) + if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; /* @@ -886,7 +879,7 @@ static int ext4_file_open(struct inode *inode, struct file *filp) { int ret; - if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb)))) + if (unlikely(ext4_forced_shutdown(inode->i_sb))) return -EIO; ret = ext4_sample_last_mounted(inode->i_sb, filp->f_path.mnt); |