Commit cc4a90ac authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Dan Williams
Browse files

dax: dax_insert_mapping_entry always succeeds 



It does not return an error, so we don't need to check the return value
for IS_ERR().  Indeed, it is a bug to do so; with a sufficiently large
PFN, a legitimate DAX entry may be mistaken for an error return.

Signed-off-by: default avatarMatthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent d6dc57e2

fs/dax.c

+2 −16
Original line number Diff line number Diff line
@@ -1009,7 +1009,6 @@ static int dax_load_hole(struct address_space *mapping, void *entry, 
	unsigned long vaddr = vmf->address;

	int ret = VM_FAULT_NOPAGE;

	struct page *zero_page;

	void *entry2;

	pfn_t pfn;



	zero_page = ZERO_PAGE(0);
@@ -1019,13 +1018,8 @@ static int dax_load_hole(struct address_space *mapping, void *entry, 
	}



	pfn = page_to_pfn_t(zero_page);

	entry2 = dax_insert_mapping_entry(mapping, vmf, entry, pfn,

			RADIX_DAX_ZERO_PAGE, false);

	if (IS_ERR(entry2)) {

		ret = VM_FAULT_SIGBUS;

		goto out;

	}



	dax_insert_mapping_entry(mapping, vmf, entry, pfn, RADIX_DAX_ZERO_PAGE,

			false);

	vm_insert_mixed(vmf->vma, vaddr, pfn);

out:

	trace_dax_load_hole(inode, vmf, ret);
@@ -1337,10 +1331,6 @@ static int dax_iomap_pte_fault(struct vm_fault *vmf, pfn_t *pfnp, 


		entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,

						 0, write && !sync);

		if (IS_ERR(entry)) {

			error = PTR_ERR(entry);

			goto error_finish_iomap;

		}



		/*

		 * If we are doing synchronous page fault and inode needs fsync,
@@ -1424,8 +1414,6 @@ static int dax_pmd_load_hole(struct vm_fault *vmf, struct iomap *iomap, 
	pfn = page_to_pfn_t(zero_page);

	ret = dax_insert_mapping_entry(mapping, vmf, entry, pfn,

			RADIX_DAX_PMD | RADIX_DAX_ZERO_PAGE, false);

	if (IS_ERR(ret))

		goto fallback;



	ptl = pmd_lock(vmf->vma->vm_mm, vmf->pmd);

	if (!pmd_none(*(vmf->pmd))) {
@@ -1547,8 +1535,6 @@ static int dax_iomap_pmd_fault(struct vm_fault *vmf, pfn_t *pfnp, 


		entry = dax_insert_mapping_entry(mapping, vmf, entry, pfn,

						RADIX_DAX_PMD, write && !sync);

		if (IS_ERR(entry))

			goto finish_iomap;



		/*

		 * If we are doing synchronous page fault and inode needs fsync,

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