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-rw-r--r--mm/Kconfig3
-rw-r--r--mm/Makefile1
-rw-r--r--mm/frame_vector.c240
-rw-r--r--mm/memory.c46
4 files changed, 43 insertions, 247 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index f730605b8dcf..24c045b24b95 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -804,9 +804,6 @@ config DEVICE_PRIVATE
config VMAP_PFN
bool
-config FRAME_VECTOR
- bool
-
config ARCH_USES_HIGH_VMA_FLAGS
bool
config ARCH_HAS_PKEYS
diff --git a/mm/Makefile b/mm/Makefile
index b6cd2fffa492..135bbb65511a 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -110,7 +110,6 @@ obj-$(CONFIG_PAGE_EXTENSION) += page_ext.o
obj-$(CONFIG_CMA_DEBUGFS) += cma_debug.o
obj-$(CONFIG_USERFAULTFD) += userfaultfd.o
obj-$(CONFIG_IDLE_PAGE_TRACKING) += page_idle.o
-obj-$(CONFIG_FRAME_VECTOR) += frame_vector.o
obj-$(CONFIG_DEBUG_PAGE_REF) += debug_page_ref.o
obj-$(CONFIG_HARDENED_USERCOPY) += usercopy.o
obj-$(CONFIG_PERCPU_STATS) += percpu-stats.o
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
deleted file mode 100644
index 10f82d5643b6..000000000000
--- a/mm/frame_vector.c
+++ /dev/null
@@ -1,240 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include <linux/pagemap.h>
-#include <linux/sched.h>
-
-/**
- * get_vaddr_frames() - map virtual addresses to pfns
- * @start: starting user address
- * @nr_frames: number of pages / pfns from start to map
- * @gup_flags: flags modifying lookup behaviour
- * @vec: structure which receives pages / pfns of the addresses mapped.
- * It should have space for at least nr_frames entries.
- *
- * This function maps virtual addresses from @start and fills @vec structure
- * with page frame numbers or page pointers to corresponding pages (choice
- * depends on the type of the vma underlying the virtual address). If @start
- * belongs to a normal vma, the function grabs reference to each of the pages
- * to pin them in memory. If @start belongs to VM_IO | VM_PFNMAP vma, we don't
- * touch page structures and the caller must make sure pfns aren't reused for
- * anything else while he is using them.
- *
- * The function returns number of pages mapped which may be less than
- * @nr_frames. In particular we stop mapping if there are more vmas of
- * different type underlying the specified range of virtual addresses.
- * When the function isn't able to map a single page, it returns error.
- *
- * This function takes care of grabbing mmap_lock as necessary.
- */
-int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
- unsigned int gup_flags, struct frame_vector *vec)
-{
- struct mm_struct *mm = current->mm;
- struct vm_area_struct *vma;
- int ret = 0;
- int err;
- int locked;
-
- if (nr_frames == 0)
- return 0;
-
- if (WARN_ON_ONCE(nr_frames > vec->nr_allocated))
- nr_frames = vec->nr_allocated;
-
- start = untagged_addr(start);
-
- mmap_read_lock(mm);
- locked = 1;
- vma = find_vma_intersection(mm, start, start + 1);
- if (!vma) {
- ret = -EFAULT;
- goto out;
- }
-
- /*
- * While get_vaddr_frames() could be used for transient (kernel
- * controlled lifetime) pinning of memory pages all current
- * users establish long term (userspace controlled lifetime)
- * page pinning. Treat get_vaddr_frames() like
- * get_user_pages_longterm() and disallow it for filesystem-dax
- * mappings.
- */
- if (vma_is_fsdax(vma)) {
- ret = -EOPNOTSUPP;
- goto out;
- }
-
- if (!(vma->vm_flags & (VM_IO | VM_PFNMAP))) {
- vec->got_ref = true;
- vec->is_pfns = false;
- ret = pin_user_pages_locked(start, nr_frames,
- gup_flags, (struct page **)(vec->ptrs), &locked);
- goto out;
- }
-
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
-out:
- if (locked)
- mmap_read_unlock(mm);
- if (!ret)
- ret = -EFAULT;
- if (ret > 0)
- vec->nr_frames = ret;
- return ret;
-}
-EXPORT_SYMBOL(get_vaddr_frames);
-
-/**
- * put_vaddr_frames() - drop references to pages if get_vaddr_frames() acquired
- * them
- * @vec: frame vector to put
- *
- * Drop references to pages if get_vaddr_frames() acquired them. We also
- * invalidate the frame vector so that it is prepared for the next call into
- * get_vaddr_frames().
- */
-void put_vaddr_frames(struct frame_vector *vec)
-{
- struct page **pages;
-
- if (!vec->got_ref)
- goto out;
- pages = frame_vector_pages(vec);
- /*
- * frame_vector_pages() might needed to do a conversion when
- * get_vaddr_frames() got pages but vec was later converted to pfns.
- * But it shouldn't really fail to convert pfns back...
- */
- if (WARN_ON(IS_ERR(pages)))
- goto out;
-
- unpin_user_pages(pages, vec->nr_frames);
- vec->got_ref = false;
-out:
- vec->nr_frames = 0;
-}
-EXPORT_SYMBOL(put_vaddr_frames);
-
-/**
- * frame_vector_to_pages - convert frame vector to contain page pointers
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of page pointers. If the conversion is
- * successful, return 0. Otherwise return an error. Note that we do not grab
- * page references for the page structures.
- */
-int frame_vector_to_pages(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (!vec->is_pfns)
- return 0;
- nums = frame_vector_pfns(vec);
- for (i = 0; i < vec->nr_frames; i++)
- if (!pfn_valid(nums[i]))
- return -EINVAL;
- pages = (struct page **)nums;
- for (i = 0; i < vec->nr_frames; i++)
- pages[i] = pfn_to_page(nums[i]);
- vec->is_pfns = false;
- return 0;
-}
-EXPORT_SYMBOL(frame_vector_to_pages);
-
-/**
- * frame_vector_to_pfns - convert frame vector to contain pfns
- * @vec: frame vector to convert
- *
- * Convert @vec to contain array of pfns.
- */
-void frame_vector_to_pfns(struct frame_vector *vec)
-{
- int i;
- unsigned long *nums;
- struct page **pages;
-
- if (vec->is_pfns)
- return;
- pages = (struct page **)(vec->ptrs);
- nums = (unsigned long *)pages;
- for (i = 0; i < vec->nr_frames; i++)
- nums[i] = page_to_pfn(pages[i]);
- vec->is_pfns = true;
-}
-EXPORT_SYMBOL(frame_vector_to_pfns);
-
-/**
- * frame_vector_create() - allocate & initialize structure for pinned pfns
- * @nr_frames: number of pfns slots we should reserve
- *
- * Allocate and initialize struct pinned_pfns to be able to hold @nr_pfns
- * pfns.
- */
-struct frame_vector *frame_vector_create(unsigned int nr_frames)
-{
- struct frame_vector *vec;
- int size = sizeof(struct frame_vector) + sizeof(void *) * nr_frames;
-
- if (WARN_ON_ONCE(nr_frames == 0))
- return NULL;
- /*
- * This is absurdly high. It's here just to avoid strange effects when
- * arithmetics overflows.
- */
- if (WARN_ON_ONCE(nr_frames > INT_MAX / sizeof(void *) / 2))
- return NULL;
- /*
- * Avoid higher order allocations, use vmalloc instead. It should
- * be rare anyway.
- */
- vec = kvmalloc(size, GFP_KERNEL);
- if (!vec)
- return NULL;
- vec->nr_allocated = nr_frames;
- vec->nr_frames = 0;
- return vec;
-}
-EXPORT_SYMBOL(frame_vector_create);
-
-/**
- * frame_vector_destroy() - free memory allocated to carry frame vector
- * @vec: Frame vector to free
- *
- * Free structure allocated by frame_vector_create() to carry frames.
- */
-void frame_vector_destroy(struct frame_vector *vec)
-{
- /* Make sure put_vaddr_frames() got called properly... */
- VM_BUG_ON(vec->nr_frames > 0);
- kvfree(vec);
-}
-EXPORT_SYMBOL(frame_vector_destroy);
diff --git a/mm/memory.c b/mm/memory.c
index c32318dc11d4..5da964079678 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4798,28 +4798,68 @@ out:
return ret;
}
+/**
+ * generic_access_phys - generic implementation for iomem mmap access
+ * @vma: the vma to access
+ * @addr: userspace addres, not relative offset within @vma
+ * @buf: buffer to read/write
+ * @len: length of transfer
+ * @write: set to FOLL_WRITE when writing, otherwise reading
+ *
+ * This is a generic implementation for &vm_operations_struct.access for an
+ * iomem mapping. This callback is used by access_process_vm() when the @vma is
+ * not page based.
+ */
int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
void *buf, int len, int write)
{
resource_size_t phys_addr;
unsigned long prot = 0;
void __iomem *maddr;
- int offset = addr & (PAGE_SIZE-1);
+ pte_t *ptep, pte;
+ spinlock_t *ptl;
+ int offset = offset_in_page(addr);
+ int ret = -EINVAL;
+
+ if (!(vma->vm_flags & (VM_IO | VM_PFNMAP)))
+ return -EINVAL;
+
+retry:
+ if (follow_pte(vma->vm_mm, addr, &ptep, &ptl))
+ return -EINVAL;
+ pte = *ptep;
+ pte_unmap_unlock(ptep, ptl);
- if (follow_phys(vma, addr, write, &prot, &phys_addr))
+ prot = pgprot_val(pte_pgprot(pte));
+ phys_addr = (resource_size_t)pte_pfn(pte) << PAGE_SHIFT;
+
+ if ((write & FOLL_WRITE) && !pte_write(pte))
return -EINVAL;
maddr = ioremap_prot(phys_addr, PAGE_ALIGN(len + offset), prot);
if (!maddr)
return -ENOMEM;
+ if (follow_pte(vma->vm_mm, addr, &ptep, &ptl))
+ goto out_unmap;
+
+ if (!pte_same(pte, *ptep)) {
+ pte_unmap_unlock(ptep, ptl);
+ iounmap(maddr);
+
+ goto retry;
+ }
+
if (write)
memcpy_toio(maddr + offset, buf, len);
else
memcpy_fromio(buf, maddr + offset, len);
+ ret = len;
+ pte_unmap_unlock(ptep, ptl);
+out_unmap:
iounmap(maddr);
- return len;
+ return ret;
}
EXPORT_SYMBOL_GPL(generic_access_phys);
#endif