| Message ID | 20240328084629.2955393-4-hch@lst.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/3] virt: acrn: stop using follow_pfn | expand |
On 28.03.24 09:46, Christoph Hellwig wrote: > follow_phys is only used by two callers in arch/x86/mm/pat/memtype.c. > Move it there and hardcode the two arguments that get the same values > passed by both callers. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > arch/x86/mm/pat/memtype.c | 23 +++++++++++++++++++++-- > include/linux/mm.h | 2 -- > mm/memory.c | 28 ---------------------------- > 3 files changed, 21 insertions(+), 32 deletions(-) > > diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c > index 0d72183b5dd028..c64f07b0fc2099 100644 > --- a/arch/x86/mm/pat/memtype.c > +++ b/arch/x86/mm/pat/memtype.c > @@ -947,6 +947,25 @@ static void free_pfn_range(u64 paddr, unsigned long size) > memtype_free(paddr, paddr + size); > } > > +static int follow_phys(struct vm_area_struct *vma, unsigned long *prot, > + resource_size_t *phys) > +{ With an implicit lookup address, the function name is a bit unfortunate. "lookup_vma_pat_info()" ... not sure. Reviewed-by: David Hildenbrand <david@redhat.com>
Hi Christoph, On Thu, Mar 28, 2024 at 09:46:29AM +0100, Christoph Hellwig wrote: > follow_phys is only used by two callers in arch/x86/mm/pat/memtype.c. > Move it there and hardcode the two arguments that get the same values > passed by both callers. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > arch/x86/mm/pat/memtype.c | 23 +++++++++++++++++++++-- > include/linux/mm.h | 2 -- > mm/memory.c | 28 ---------------------------- > 3 files changed, 21 insertions(+), 32 deletions(-) > > diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c > index 0d72183b5dd028..c64f07b0fc2099 100644 > --- a/arch/x86/mm/pat/memtype.c > +++ b/arch/x86/mm/pat/memtype.c > @@ -947,6 +947,25 @@ static void free_pfn_range(u64 paddr, unsigned long size) > memtype_free(paddr, paddr + size); > } > > +static int follow_phys(struct vm_area_struct *vma, unsigned long *prot, > + resource_size_t *phys) > +{ > + pte_t *ptep, pte; > + spinlock_t *ptl; > + > + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) > + return -EINVAL; > + > + if (follow_pte(vma->vm_mm, vma->vm_start, &ptep, &ptl)) > + return -EINVAL; > + > + pte = ptep_get(ptep); > + *prot = pgprot_val(pte_pgprot(pte)); > + *phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT; > + pte_unmap_unlock(ptep, ptl); memtype.c needs to include highmem.h for highmem-internal.h, otherwise I get a build failure (ARCH=i386 allmodconfig): In file included from include/linux/mm.h:30, from include/linux/memblock.h:12, from arch/x86/mm/pat/memtype.c:35: arch/x86/mm/pat/memtype.c: In function 'follow_phys': include/linux/pgtable.h:105:9: error: implicit declaration of function 'kunmap_local' [-Werror=implicit-function-declaration] 105 | kunmap_local((pte)); \ | ^~~~~~~~~~~~ include/linux/mm.h:3014:9: note: in expansion of macro 'pte_unmap' 3014 | pte_unmap(pte); \ | ^~~~~~~~~ arch/x86/mm/pat/memtype.c:965:9: note: in expansion of macro 'pte_unmap_unlock' 965 | pte_unmap_unlock(ptep, ptl); | ^~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors Cheers, Nathan diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index c64f07b0fc20..143d1e3d3fd2 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -39,6 +39,7 @@ #include <linux/pfn_t.h> #include <linux/slab.h> #include <linux/mm.h> +#include <linux/highmem.h> #include <linux/fs.h> #include <linux/rbtree.h>
diff --git a/arch/x86/mm/pat/memtype.c b/arch/x86/mm/pat/memtype.c index 0d72183b5dd028..c64f07b0fc2099 100644 --- a/arch/x86/mm/pat/memtype.c +++ b/arch/x86/mm/pat/memtype.c @@ -947,6 +947,25 @@ static void free_pfn_range(u64 paddr, unsigned long size) memtype_free(paddr, paddr + size); } +static int follow_phys(struct vm_area_struct *vma, unsigned long *prot, + resource_size_t *phys) +{ + pte_t *ptep, pte; + spinlock_t *ptl; + + if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) + return -EINVAL; + + if (follow_pte(vma->vm_mm, vma->vm_start, &ptep, &ptl)) + return -EINVAL; + + pte = ptep_get(ptep); + *prot = pgprot_val(pte_pgprot(pte)); + *phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT; + pte_unmap_unlock(ptep, ptl); + return 0; +} + /* * track_pfn_copy is called when vma that is covering the pfnmap gets * copied through copy_page_range(). @@ -966,7 +985,7 @@ int track_pfn_copy(struct vm_area_struct *vma) * reserve the whole chunk covered by vma. We need the * starting address and protection from pte. */ - if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) { + if (follow_phys(vma, &prot, &paddr)) { WARN_ON_ONCE(1); return -EINVAL; } @@ -1053,7 +1072,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, /* free the chunk starting from pfn or the whole chunk */ paddr = (resource_size_t)pfn << PAGE_SHIFT; if (!paddr && !size) { - if (follow_phys(vma, vma->vm_start, 0, &prot, &paddr)) { + if (follow_phys(vma, &prot, &paddr)) { WARN_ON_ONCE(1); return; } diff --git a/include/linux/mm.h b/include/linux/mm.h index 9cd2c69f913601..51cfc8267da755 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2393,8 +2393,6 @@ int copy_page_range(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma); int follow_pte(struct mm_struct *mm, unsigned long address, pte_t **ptepp, spinlock_t **ptlp); -int follow_phys(struct vm_area_struct *vma, unsigned long address, - unsigned int flags, unsigned long *prot, resource_size_t *phys); int generic_access_phys(struct vm_area_struct *vma, unsigned long addr, void *buf, int len, int write); diff --git a/mm/memory.c b/mm/memory.c index 33559720f0aab9..86c9eb92b5e03c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -5926,34 +5926,6 @@ int follow_pte(struct mm_struct *mm, unsigned long address, EXPORT_SYMBOL_GPL(follow_pte); #ifdef CONFIG_HAVE_IOREMAP_PROT -int follow_phys(struct vm_area_struct *vma, - unsigned long address, unsigned int flags, - unsigned long *prot, resource_size_t *phys) -{ - int ret = -EINVAL; - pte_t *ptep, pte; - spinlock_t *ptl; - - if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) - goto out; - - if (follow_pte(vma->vm_mm, address, &ptep, &ptl)) - goto out; - pte = ptep_get(ptep); - - if ((flags & FOLL_WRITE) && !pte_write(pte)) - goto unlock; - - *prot = pgprot_val(pte_pgprot(pte)); - *phys = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT; - - ret = 0; -unlock: - pte_unmap_unlock(ptep, ptl); -out: - return ret; -} - /** * generic_access_phys - generic implementation for iomem mmap access * @vma: the vma to access
follow_phys is only used by two callers in arch/x86/mm/pat/memtype.c. Move it there and hardcode the two arguments that get the same values passed by both callers. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/x86/mm/pat/memtype.c | 23 +++++++++++++++++++++-- include/linux/mm.h | 2 -- mm/memory.c | 28 ---------------------------- 3 files changed, 21 insertions(+), 32 deletions(-)