mm: remove follow_pfn

Remove follow_pfn now that the last user is gone.

Link: https://lkml.kernel.org/r/20240324234542.2038726-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fei Li <fei1.li@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Christoph Hellwig 2024-03-25 07:45:41 +08:00 committed by Andrew Morton
parent 1b265da7ea
commit cb10c28ac8
3 changed files with 2 additions and 57 deletions

View File

@ -2424,8 +2424,6 @@ 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_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);
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,

View File

@ -5884,8 +5884,8 @@ int __pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
* Only IO mappings and raw PFN mappings are allowed. The mmap semaphore
* should be taken for read.
*
* KVM uses this function. While it is arguably less bad than ``follow_pfn``,
* it is not a good general-purpose API.
* KVM uses this function. While it is arguably less bad than the historic
* ``follow_pfn``, it is not a good general-purpose API.
*
* Return: zero on success, -ve otherwise.
*/
@ -5927,38 +5927,6 @@ int follow_pte(struct mm_struct *mm, unsigned long address,
}
EXPORT_SYMBOL_GPL(follow_pte);
/**
* follow_pfn - look up PFN at a user virtual address
* @vma: memory mapping
* @address: user virtual address
* @pfn: location to store found PFN
*
* Only IO mappings and raw PFN mappings are allowed.
*
* This function does not allow the caller to read the permissions
* of the PTE. Do not use it.
*
* Return: zero and the pfn at @pfn on success, -ve otherwise.
*/
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
unsigned long *pfn)
{
int ret = -EINVAL;
spinlock_t *ptl;
pte_t *ptep;
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
return ret;
ret = follow_pte(vma->vm_mm, address, &ptep, &ptl);
if (ret)
return ret;
*pfn = pte_pfn(ptep_get(ptep));
pte_unmap_unlock(ptep, ptl);
return 0;
}
EXPORT_SYMBOL(follow_pfn);
#ifdef CONFIG_HAVE_IOREMAP_PROT
int follow_phys(struct vm_area_struct *vma,
unsigned long address, unsigned int flags,

View File

@ -110,27 +110,6 @@ unsigned int kobjsize(const void *objp)
return page_size(page);
}
/**
* follow_pfn - look up PFN at a user virtual address
* @vma: memory mapping
* @address: user virtual address
* @pfn: location to store found PFN
*
* Only IO mappings and raw PFN mappings are allowed.
*
* Returns zero and the pfn at @pfn on success, -ve otherwise.
*/
int follow_pfn(struct vm_area_struct *vma, unsigned long address,
unsigned long *pfn)
{
if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
return -EINVAL;
*pfn = address >> PAGE_SHIFT;
return 0;
}
EXPORT_SYMBOL(follow_pfn);
void vfree(const void *addr)
{
kfree(addr);