Make default vm_ops provide ->page_mkwrite handler. Currently it only updates file's modification times and gets locked page but later it will also handle filesystem freezing. BugLink: https://bugs.launchpad.net/bugs/897421 Tested-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx> Tested-by: Peter M. Petrakis <peter.petrakis@xxxxxxxxxxxxx> Tested-by: Dann Frazier <dann.frazier@xxxxxxxxxxxxx> Tested-by: Massimo Morana <massimo.morana@xxxxxxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> --- include/linux/mm.h | 1 + mm/filemap.c | 19 +++++++++++++++++++ mm/filemap_xip.c | 1 + 3 files changed, 21 insertions(+), 0 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 17b27cd..074c075 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1419,6 +1419,7 @@ extern void truncate_inode_pages_range(struct address_space *, /* generic vm_area_ops exported for stackable file systems */ extern int filemap_fault(struct vm_area_struct *, struct vm_fault *); +extern int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf); /* mm/page-writeback.c */ int write_one_page(struct page *page, int wait); diff --git a/mm/filemap.c b/mm/filemap.c index b662757..fbd69e3 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1759,8 +1759,27 @@ page_not_uptodate: } EXPORT_SYMBOL(filemap_fault); +int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) +{ + struct page *page = vmf->page; + struct inode *inode = vma->vm_file->f_path.dentry->d_inode; + int ret = VM_FAULT_LOCKED; + + file_update_time(vma->vm_file); + lock_page(page); + if (page->mapping != inode->i_mapping) { + unlock_page(page); + ret = VM_FAULT_NOPAGE; + goto out; + } +out: + return ret; +} +EXPORT_SYMBOL(filemap_page_mkwrite); + const struct vm_operations_struct generic_file_vm_ops = { .fault = filemap_fault, + .page_mkwrite = filemap_page_mkwrite, }; /* This is used for a general mmap of a disk file */ diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c index a4eb311..591dba6 100644 --- a/mm/filemap_xip.c +++ b/mm/filemap_xip.c @@ -304,6 +304,7 @@ out: static const struct vm_operations_struct xip_file_vm_ops = { .fault = xip_file_fault, + .page_mkwrite = filemap_page_mkwrite, }; int xip_file_mmap(struct file * file, struct vm_area_struct * vma) -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
