On Fri, Jun 10, 2022 at 06:41:54AM -0700, Wang Wenhu wrote: > It is recommended in the "Conditional Compilation" chapter of kernel > coding-style documentation that preprocessor conditionals should not > be used in .c files wherever possible. > > As for the micro CONFIG_HAVE_IOREMAP_PROT, now it's a proper chance > to eliminate it in .c files as we add a no-op function defination > in the header file if the micro is not enabled. s/micro/macro/ (twice) s/defination/definition/ > The main trigger for this patch is an UIO driver series and as Greg > commented we'd better not use such preprocessor contionals. s/contionals/conditionals/ > See: https://lore.kernel.org/lkml/YqHy1uXwCLlJmftr@xxxxxxxxx/ > For there is little work to do with the UIO driver, I try to push > this commit independently. > > Signed-off-by: Wang Wenhu <lonehugo@xxxxxxxxxxx> Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> # drivers/pci/ Thanks for cleaning this up! > --- > v2: specify no-op function definition with static inline > --- > drivers/char/mem.c | 2 -- > drivers/fpga/dfl-afu-main.c | 2 -- > drivers/pci/mmap.c | 2 -- > drivers/uio/uio.c | 2 -- > include/linux/mm.h | 8 ++++++++ > mm/memory.c | 4 ---- > 6 files changed, 8 insertions(+), 12 deletions(-) > > diff --git a/drivers/char/mem.c b/drivers/char/mem.c > index 84ca98ed1dad..40186a441e38 100644 > --- a/drivers/char/mem.c > +++ b/drivers/char/mem.c > @@ -354,9 +354,7 @@ static inline int private_mapping_ok(struct vm_area_struct *vma) > #endif > > static const struct vm_operations_struct mmap_mem_ops = { > -#ifdef CONFIG_HAVE_IOREMAP_PROT > .access = generic_access_phys > -#endif > }; > > static int mmap_mem(struct file *file, struct vm_area_struct *vma) > diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c > index 7f621e96d3b8..833e14806c7a 100644 > --- a/drivers/fpga/dfl-afu-main.c > +++ b/drivers/fpga/dfl-afu-main.c > @@ -797,9 +797,7 @@ static long afu_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > } > > static const struct vm_operations_struct afu_vma_ops = { > -#ifdef CONFIG_HAVE_IOREMAP_PROT > .access = generic_access_phys, > -#endif > }; > > static int afu_mmap(struct file *filp, struct vm_area_struct *vma) > diff --git a/drivers/pci/mmap.c b/drivers/pci/mmap.c > index b8c9011987f4..1dcfabf80453 100644 > --- a/drivers/pci/mmap.c > +++ b/drivers/pci/mmap.c > @@ -35,9 +35,7 @@ int pci_mmap_page_range(struct pci_dev *pdev, int bar, > #endif > > static const struct vm_operations_struct pci_phys_vm_ops = { > -#ifdef CONFIG_HAVE_IOREMAP_PROT > .access = generic_access_phys, > -#endif > }; > > int pci_mmap_resource_range(struct pci_dev *pdev, int bar, > diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c > index 43afbb7c5ab9..c9205a121007 100644 > --- a/drivers/uio/uio.c > +++ b/drivers/uio/uio.c > @@ -719,9 +719,7 @@ static int uio_mmap_logical(struct vm_area_struct *vma) > } > > static const struct vm_operations_struct uio_physical_vm_ops = { > -#ifdef CONFIG_HAVE_IOREMAP_PROT > .access = generic_access_phys, > -#endif > }; > > static int uio_mmap_physical(struct vm_area_struct *vma) > diff --git a/include/linux/mm.h b/include/linux/mm.h > index bc8f326be0ce..60c183dce5ea 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -1857,8 +1857,16 @@ int follow_pfn(struct vm_area_struct *vma, unsigned long address, > unsigned long *pfn); > int follow_phys(struct vm_area_struct *vma, unsigned long address, > unsigned int flags, unsigned long *prot, resource_size_t *phys); > +#ifdef CONFIG_HAVE_IOREMAP_PROT > int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, > void *buf, int len, int write); > +#else > +static inline int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, > + void *buf, int len, int write) > +{ > + return 0; > +} > +#endif > > extern void truncate_pagecache(struct inode *inode, loff_t new); > extern void truncate_setsize(struct inode *inode, loff_t newsize); > diff --git a/mm/memory.c b/mm/memory.c > index 7a089145cad4..79b94db1bd5e 100644 > --- a/mm/memory.c > +++ b/mm/memory.c > @@ -5437,9 +5437,6 @@ int __access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, > ret = get_user_pages_remote(mm, addr, 1, > gup_flags, &page, &vma, NULL); > if (ret <= 0) { > -#ifndef CONFIG_HAVE_IOREMAP_PROT > - break; > -#else > /* > * Check if this is a VM_IO | VM_PFNMAP VMA, which > * we can access using slightly different code. > @@ -5453,7 +5450,6 @@ int __access_remote_vm(struct mm_struct *mm, unsigned long addr, void *buf, > if (ret <= 0) > break; > bytes = ret; > -#endif > } else { > bytes = len; > offset = addr & (PAGE_SIZE-1); > -- > 2.25.1 >
