From 302a5e312b3a106fec49ba08da3f6545c9b7ee18 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 1 Nov 2017 16:36:37 +0100 Subject: dax: Inline dax_pmd_insert_mapping() into the callsite dax_pmd_insert_mapping() has only one callsite and we will need to further fine tune what it does for synchronous faults. Just inline it into the callsite so that we don't have to pass awkward bools around. Reviewed-by: Christoph Hellwig Reviewed-by: Ross Zwisler Signed-off-by: Jan Kara Signed-off-by: Dan Williams --- include/trace/events/fs_dax.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/trace') diff --git a/include/trace/events/fs_dax.h b/include/trace/events/fs_dax.h index fbc4a06f7310..88a9d19b8ff8 100644 --- a/include/trace/events/fs_dax.h +++ b/include/trace/events/fs_dax.h @@ -148,7 +148,6 @@ DEFINE_EVENT(dax_pmd_insert_mapping_class, name, \ TP_ARGS(inode, vmf, length, pfn, radix_entry)) DEFINE_PMD_INSERT_MAPPING_EVENT(dax_pmd_insert_mapping); -DEFINE_PMD_INSERT_MAPPING_EVENT(dax_pmd_insert_mapping_fallback); DECLARE_EVENT_CLASS(dax_pte_fault_class, TP_PROTO(struct inode *inode, struct vm_fault *vmf, int result), -- cgit v1.2.3 From 71eab6dfd91eabf06fe782a590c07e8a0795f5ea Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Wed, 1 Nov 2017 16:36:43 +0100 Subject: dax: Implement dax_finish_sync_fault() Implement a function that filesystems can call to finish handling of synchronous page faults. It takes care of syncing appropriare file range and insertion of page table entry. Reviewed-by: Ross Zwisler Reviewed-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Dan Williams --- fs/dax.c | 83 +++++++++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 2 ++ include/trace/events/fs_dax.h | 2 ++ 3 files changed, 87 insertions(+) (limited to 'include/trace') diff --git a/fs/dax.c b/fs/dax.c index bb9ff907738c..78233c716757 100644 --- a/fs/dax.c +++ b/fs/dax.c @@ -1492,3 +1492,86 @@ int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size, } } EXPORT_SYMBOL_GPL(dax_iomap_fault); + +/** + * dax_insert_pfn_mkwrite - insert PTE or PMD entry into page tables + * @vmf: The description of the fault + * @pe_size: Size of entry to be inserted + * @pfn: PFN to insert + * + * This function inserts writeable PTE or PMD entry into page tables for mmaped + * DAX file. It takes care of marking corresponding radix tree entry as dirty + * as well. + */ +static int dax_insert_pfn_mkwrite(struct vm_fault *vmf, + enum page_entry_size pe_size, + pfn_t pfn) +{ + struct address_space *mapping = vmf->vma->vm_file->f_mapping; + void *entry, **slot; + pgoff_t index = vmf->pgoff; + int vmf_ret, error; + + spin_lock_irq(&mapping->tree_lock); + entry = get_unlocked_mapping_entry(mapping, index, &slot); + /* Did we race with someone splitting entry or so? */ + if (!entry || + (pe_size == PE_SIZE_PTE && !dax_is_pte_entry(entry)) || + (pe_size == PE_SIZE_PMD && !dax_is_pmd_entry(entry))) { + put_unlocked_mapping_entry(mapping, index, entry); + spin_unlock_irq(&mapping->tree_lock); + trace_dax_insert_pfn_mkwrite_no_entry(mapping->host, vmf, + VM_FAULT_NOPAGE); + return VM_FAULT_NOPAGE; + } + radix_tree_tag_set(&mapping->page_tree, index, PAGECACHE_TAG_DIRTY); + entry = lock_slot(mapping, slot); + spin_unlock_irq(&mapping->tree_lock); + switch (pe_size) { + case PE_SIZE_PTE: + error = vm_insert_mixed_mkwrite(vmf->vma, vmf->address, pfn); + vmf_ret = dax_fault_return(error); + break; +#ifdef CONFIG_FS_DAX_PMD + case PE_SIZE_PMD: + vmf_ret = vmf_insert_pfn_pmd(vmf->vma, vmf->address, vmf->pmd, + pfn, true); + break; +#endif + default: + vmf_ret = VM_FAULT_FALLBACK; + } + put_locked_mapping_entry(mapping, index); + trace_dax_insert_pfn_mkwrite(mapping->host, vmf, vmf_ret); + return vmf_ret; +} + +/** + * dax_finish_sync_fault - finish synchronous page fault + * @vmf: The description of the fault + * @pe_size: Size of entry to be inserted + * @pfn: PFN to insert + * + * This function ensures that the file range touched by the page fault is + * stored persistently on the media and handles inserting of appropriate page + * table entry. + */ +int dax_finish_sync_fault(struct vm_fault *vmf, enum page_entry_size pe_size, + pfn_t pfn) +{ + int err; + loff_t start = ((loff_t)vmf->pgoff) << PAGE_SHIFT; + size_t len = 0; + + if (pe_size == PE_SIZE_PTE) + len = PAGE_SIZE; + else if (pe_size == PE_SIZE_PMD) + len = PMD_SIZE; + else + WARN_ON_ONCE(1); + err = vfs_fsync_range(vmf->vma->vm_file, start, start + len - 1, 1); + if (err) + return VM_FAULT_SIGBUS; + return dax_insert_pfn_mkwrite(vmf, pe_size, pfn); +} +EXPORT_SYMBOL_GPL(dax_finish_sync_fault); diff --git a/include/linux/dax.h b/include/linux/dax.h index e7fa4b8f45bc..d403f78b706c 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -96,6 +96,8 @@ ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter, const struct iomap_ops *ops); int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size, pfn_t *pfnp, const struct iomap_ops *ops); +int dax_finish_sync_fault(struct vm_fault *vmf, enum page_entry_size pe_size, + pfn_t pfn); int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index); int dax_invalidate_mapping_entry_sync(struct address_space *mapping, pgoff_t index); diff --git a/include/trace/events/fs_dax.h b/include/trace/events/fs_dax.h index 88a9d19b8ff8..7725459fafef 100644 --- a/include/trace/events/fs_dax.h +++ b/include/trace/events/fs_dax.h @@ -190,6 +190,8 @@ DEFINE_EVENT(dax_pte_fault_class, name, \ DEFINE_PTE_FAULT_EVENT(dax_pte_fault); DEFINE_PTE_FAULT_EVENT(dax_pte_fault_done); DEFINE_PTE_FAULT_EVENT(dax_load_hole); +DEFINE_PTE_FAULT_EVENT(dax_insert_pfn_mkwrite_no_entry); +DEFINE_PTE_FAULT_EVENT(dax_insert_pfn_mkwrite); TRACE_EVENT(dax_insert_mapping, TP_PROTO(struct inode *inode, struct vm_fault *vmf, void *radix_entry), -- cgit v1.2.3