[PATCH 6/7] vfio: moving some functions in common file
Bharat Bhushan
r65777 at freescale.com
Thu Sep 19 17:29:22 EST 2013
Some function defined in vfio_iommu_type1.c were common and
we want to use these for FSL IOMMU (PAMU) and iommu-none driver.
So some of them are moved to vfio_iommu_common.c
I think we can do more of that but we will take this step by step.
Signed-off-by: Bharat Bhushan <bharat.bhushan at freescale.com>
---
drivers/vfio/Makefile | 4 +-
drivers/vfio/vfio_iommu_common.c | 235 ++++++++++++++++++++++++++++++++++++++
drivers/vfio/vfio_iommu_common.h | 30 +++++
drivers/vfio/vfio_iommu_type1.c | 206 +---------------------------------
4 files changed, 268 insertions(+), 207 deletions(-)
create mode 100644 drivers/vfio/vfio_iommu_common.c
create mode 100644 drivers/vfio/vfio_iommu_common.h
diff --git a/drivers/vfio/Makefile b/drivers/vfio/Makefile
index 72bfabc..c5792ec 100644
--- a/drivers/vfio/Makefile
+++ b/drivers/vfio/Makefile
@@ -1,4 +1,4 @@
obj-$(CONFIG_VFIO) += vfio.o
-obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_type1.o
-obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_spapr_tce.o
+obj-$(CONFIG_VFIO_IOMMU_TYPE1) += vfio_iommu_common.o vfio_iommu_type1.o
+obj-$(CONFIG_VFIO_IOMMU_SPAPR_TCE) += vfio_iommu_common.o vfio_iommu_spapr_tce.o
obj-$(CONFIG_VFIO_PCI) += pci/
diff --git a/drivers/vfio/vfio_iommu_common.c b/drivers/vfio/vfio_iommu_common.c
new file mode 100644
index 0000000..8bdc0ea
--- /dev/null
+++ b/drivers/vfio/vfio_iommu_common.c
@@ -0,0 +1,235 @@
+/*
+ * VFIO: Common code for vfio IOMMU support
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
+ * Author: Alex Williamson <alex.williamson at redhat.com>
+ * Author: Bharat Bhushan <bharat.bhushan at freescale.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Derived from original vfio:
+ * Copyright 2010 Cisco Systems, Inc. All rights reserved.
+ * Author: Tom Lyon, pugs at cisco.com
+ */
+
+#include <linux/compat.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/iommu.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/pci.h> /* pci_bus_type */
+#include <linux/rbtree.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/vfio.h>
+#include <linux/workqueue.h>
+
+static bool disable_hugepages;
+module_param_named(disable_hugepages,
+ disable_hugepages, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(disable_hugepages,
+ "Disable VFIO IOMMU support for IOMMU hugepages.");
+
+struct vwork {
+ struct mm_struct *mm;
+ long npage;
+ struct work_struct work;
+};
+
+/* delayed decrement/increment for locked_vm */
+void vfio_lock_acct_bg(struct work_struct *work)
+{
+ struct vwork *vwork = container_of(work, struct vwork, work);
+ struct mm_struct *mm;
+
+ mm = vwork->mm;
+ down_write(&mm->mmap_sem);
+ mm->locked_vm += vwork->npage;
+ up_write(&mm->mmap_sem);
+ mmput(mm);
+ kfree(vwork);
+}
+
+void vfio_lock_acct(long npage)
+{
+ struct vwork *vwork;
+ struct mm_struct *mm;
+
+ if (!current->mm || !npage)
+ return; /* process exited or nothing to do */
+
+ if (down_write_trylock(¤t->mm->mmap_sem)) {
+ current->mm->locked_vm += npage;
+ up_write(¤t->mm->mmap_sem);
+ return;
+ }
+
+ /*
+ * Couldn't get mmap_sem lock, so must setup to update
+ * mm->locked_vm later. If locked_vm were atomic, we
+ * wouldn't need this silliness
+ */
+ vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
+ if (!vwork)
+ return;
+ mm = get_task_mm(current);
+ if (!mm) {
+ kfree(vwork);
+ return;
+ }
+ INIT_WORK(&vwork->work, vfio_lock_acct_bg);
+ vwork->mm = mm;
+ vwork->npage = npage;
+ schedule_work(&vwork->work);
+}
+
+/*
+ * Some mappings aren't backed by a struct page, for example an mmap'd
+ * MMIO range for our own or another device. These use a different
+ * pfn conversion and shouldn't be tracked as locked pages.
+ */
+bool is_invalid_reserved_pfn(unsigned long pfn)
+{
+ if (pfn_valid(pfn)) {
+ bool reserved;
+ struct page *tail = pfn_to_page(pfn);
+ struct page *head = compound_trans_head(tail);
+ reserved = !!(PageReserved(head));
+ if (head != tail) {
+ /*
+ * "head" is not a dangling pointer
+ * (compound_trans_head takes care of that)
+ * but the hugepage may have been split
+ * from under us (and we may not hold a
+ * reference count on the head page so it can
+ * be reused before we run PageReferenced), so
+ * we've to check PageTail before returning
+ * what we just read.
+ */
+ smp_rmb();
+ if (PageTail(tail))
+ return reserved;
+ }
+ return PageReserved(tail);
+ }
+
+ return true;
+}
+
+int put_pfn(unsigned long pfn, int prot)
+{
+ if (!is_invalid_reserved_pfn(pfn)) {
+ struct page *page = pfn_to_page(pfn);
+ if (prot & IOMMU_WRITE)
+ SetPageDirty(page);
+ put_page(page);
+ return 1;
+ }
+ return 0;
+}
+
+static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
+{
+ struct page *page[1];
+ struct vm_area_struct *vma;
+ int ret = -EFAULT;
+
+ if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
+ *pfn = page_to_pfn(page[0]);
+ return 0;
+ }
+
+ printk("via vma\n");
+ down_read(¤t->mm->mmap_sem);
+
+ vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
+
+ if (vma && vma->vm_flags & VM_PFNMAP) {
+ *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ if (is_invalid_reserved_pfn(*pfn))
+ ret = 0;
+ }
+
+ up_read(¤t->mm->mmap_sem);
+
+ return ret;
+}
+
+/*
+ * Attempt to pin pages. We really don't want to track all the pfns and
+ * the iommu can only map chunks of consecutive pfns anyway, so get the
+ * first page and all consecutive pages with the same locking.
+ */
+long vfio_pin_pages(unsigned long vaddr, long npage,
+ int prot, unsigned long *pfn_base)
+{
+ unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ bool lock_cap = capable(CAP_IPC_LOCK);
+ long ret, i;
+
+ if (!current->mm)
+ return -ENODEV;
+
+ ret = vaddr_get_pfn(vaddr, prot, pfn_base);
+ if (ret)
+ return ret;
+
+ if (is_invalid_reserved_pfn(*pfn_base))
+ return 1;
+
+ if (!lock_cap && current->mm->locked_vm + 1 > limit) {
+ put_pfn(*pfn_base, prot);
+ pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
+ limit << PAGE_SHIFT);
+ return -ENOMEM;
+ }
+
+ if (unlikely(disable_hugepages)) {
+ vfio_lock_acct(1);
+ return 1;
+ }
+
+ /* Lock all the consecutive pages from pfn_base */
+ for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
+ unsigned long pfn = 0;
+
+ ret = vaddr_get_pfn(vaddr, prot, &pfn);
+ if (ret)
+ break;
+
+ if (pfn != *pfn_base + i || is_invalid_reserved_pfn(pfn)) {
+ put_pfn(pfn, prot);
+ break;
+ }
+
+ if (!lock_cap && current->mm->locked_vm + i + 1 > limit) {
+ put_pfn(pfn, prot);
+ pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
+ __func__, limit << PAGE_SHIFT);
+ break;
+ }
+ }
+
+ vfio_lock_acct(i);
+
+ return i;
+}
+
+long vfio_unpin_pages(unsigned long pfn, long npage,
+ int prot, bool do_accounting)
+{
+ unsigned long unlocked = 0;
+ long i;
+
+ for (i = 0; i < npage; i++)
+ unlocked += put_pfn(pfn++, prot);
+
+ if (do_accounting)
+ vfio_lock_acct(-unlocked);
+
+ return unlocked;
+}
diff --git a/drivers/vfio/vfio_iommu_common.h b/drivers/vfio/vfio_iommu_common.h
new file mode 100644
index 0000000..4738391
--- /dev/null
+++ b/drivers/vfio/vfio_iommu_common.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2013 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _VFIO_IOMMU_COMMON_H
+#define _VFIO_IOMMU_COMMON_H
+
+void vfio_lock_acct_bg(struct work_struct *work);
+void vfio_lock_acct(long npage);
+bool is_invalid_reserved_pfn(unsigned long pfn);
+int put_pfn(unsigned long pfn, int prot);
+long vfio_pin_pages(unsigned long vaddr, long npage, int prot,
+ unsigned long *pfn_base);
+long vfio_unpin_pages(unsigned long pfn, long npage,
+ int prot, bool do_accounting);
+#endif
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index a9807de..e9a58fa 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -37,6 +37,7 @@
#include <linux/uaccess.h>
#include <linux/vfio.h>
#include <linux/workqueue.h>
+#include "vfio_iommu_common.h"
#define DRIVER_VERSION "0.2"
#define DRIVER_AUTHOR "Alex Williamson <alex.williamson at redhat.com>"
@@ -48,12 +49,6 @@ module_param_named(allow_unsafe_interrupts,
MODULE_PARM_DESC(allow_unsafe_interrupts,
"Enable VFIO IOMMU support for on platforms without interrupt remapping support.");
-static bool disable_hugepages;
-module_param_named(disable_hugepages,
- disable_hugepages, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(disable_hugepages,
- "Disable VFIO IOMMU support for IOMMU hugepages.");
-
struct vfio_iommu {
struct iommu_domain *domain;
struct mutex lock;
@@ -123,205 +118,6 @@ static void vfio_remove_dma(struct vfio_iommu *iommu, struct vfio_dma *old)
rb_erase(&old->node, &iommu->dma_list);
}
-struct vwork {
- struct mm_struct *mm;
- long npage;
- struct work_struct work;
-};
-
-/* delayed decrement/increment for locked_vm */
-static void vfio_lock_acct_bg(struct work_struct *work)
-{
- struct vwork *vwork = container_of(work, struct vwork, work);
- struct mm_struct *mm;
-
- mm = vwork->mm;
- down_write(&mm->mmap_sem);
- mm->locked_vm += vwork->npage;
- up_write(&mm->mmap_sem);
- mmput(mm);
- kfree(vwork);
-}
-
-static void vfio_lock_acct(long npage)
-{
- struct vwork *vwork;
- struct mm_struct *mm;
-
- if (!current->mm || !npage)
- return; /* process exited or nothing to do */
-
- if (down_write_trylock(¤t->mm->mmap_sem)) {
- current->mm->locked_vm += npage;
- up_write(¤t->mm->mmap_sem);
- return;
- }
-
- /*
- * Couldn't get mmap_sem lock, so must setup to update
- * mm->locked_vm later. If locked_vm were atomic, we
- * wouldn't need this silliness
- */
- vwork = kmalloc(sizeof(struct vwork), GFP_KERNEL);
- if (!vwork)
- return;
- mm = get_task_mm(current);
- if (!mm) {
- kfree(vwork);
- return;
- }
- INIT_WORK(&vwork->work, vfio_lock_acct_bg);
- vwork->mm = mm;
- vwork->npage = npage;
- schedule_work(&vwork->work);
-}
-
-/*
- * Some mappings aren't backed by a struct page, for example an mmap'd
- * MMIO range for our own or another device. These use a different
- * pfn conversion and shouldn't be tracked as locked pages.
- */
-static bool is_invalid_reserved_pfn(unsigned long pfn)
-{
- if (pfn_valid(pfn)) {
- bool reserved;
- struct page *tail = pfn_to_page(pfn);
- struct page *head = compound_trans_head(tail);
- reserved = !!(PageReserved(head));
- if (head != tail) {
- /*
- * "head" is not a dangling pointer
- * (compound_trans_head takes care of that)
- * but the hugepage may have been split
- * from under us (and we may not hold a
- * reference count on the head page so it can
- * be reused before we run PageReferenced), so
- * we've to check PageTail before returning
- * what we just read.
- */
- smp_rmb();
- if (PageTail(tail))
- return reserved;
- }
- return PageReserved(tail);
- }
-
- return true;
-}
-
-static int put_pfn(unsigned long pfn, int prot)
-{
- if (!is_invalid_reserved_pfn(pfn)) {
- struct page *page = pfn_to_page(pfn);
- if (prot & IOMMU_WRITE)
- SetPageDirty(page);
- put_page(page);
- return 1;
- }
- return 0;
-}
-
-static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn)
-{
- struct page *page[1];
- struct vm_area_struct *vma;
- int ret = -EFAULT;
-
- if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) {
- *pfn = page_to_pfn(page[0]);
- return 0;
- }
-
- down_read(¤t->mm->mmap_sem);
-
- vma = find_vma_intersection(current->mm, vaddr, vaddr + 1);
-
- if (vma && vma->vm_flags & VM_PFNMAP) {
- *pfn = ((vaddr - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
- if (is_invalid_reserved_pfn(*pfn))
- ret = 0;
- }
-
- up_read(¤t->mm->mmap_sem);
-
- return ret;
-}
-
-/*
- * Attempt to pin pages. We really don't want to track all the pfns and
- * the iommu can only map chunks of consecutive pfns anyway, so get the
- * first page and all consecutive pages with the same locking.
- */
-static long vfio_pin_pages(unsigned long vaddr, long npage,
- int prot, unsigned long *pfn_base)
-{
- unsigned long limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
- bool lock_cap = capable(CAP_IPC_LOCK);
- long ret, i;
-
- if (!current->mm)
- return -ENODEV;
-
- ret = vaddr_get_pfn(vaddr, prot, pfn_base);
- if (ret)
- return ret;
-
- if (is_invalid_reserved_pfn(*pfn_base))
- return 1;
-
- if (!lock_cap && current->mm->locked_vm + 1 > limit) {
- put_pfn(*pfn_base, prot);
- pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n", __func__,
- limit << PAGE_SHIFT);
- return -ENOMEM;
- }
-
- if (unlikely(disable_hugepages)) {
- vfio_lock_acct(1);
- return 1;
- }
-
- /* Lock all the consecutive pages from pfn_base */
- for (i = 1, vaddr += PAGE_SIZE; i < npage; i++, vaddr += PAGE_SIZE) {
- unsigned long pfn = 0;
-
- ret = vaddr_get_pfn(vaddr, prot, &pfn);
- if (ret)
- break;
-
- if (pfn != *pfn_base + i || is_invalid_reserved_pfn(pfn)) {
- put_pfn(pfn, prot);
- break;
- }
-
- if (!lock_cap && current->mm->locked_vm + i + 1 > limit) {
- put_pfn(pfn, prot);
- pr_warn("%s: RLIMIT_MEMLOCK (%ld) exceeded\n",
- __func__, limit << PAGE_SHIFT);
- break;
- }
- }
-
- vfio_lock_acct(i);
-
- return i;
-}
-
-static long vfio_unpin_pages(unsigned long pfn, long npage,
- int prot, bool do_accounting)
-{
- unsigned long unlocked = 0;
- long i;
-
- for (i = 0; i < npage; i++)
- unlocked += put_pfn(pfn++, prot);
-
- if (do_accounting)
- vfio_lock_acct(-unlocked);
-
- return unlocked;
-}
-
static int vfio_unmap_unpin(struct vfio_iommu *iommu, struct vfio_dma *dma,
dma_addr_t iova, size_t *size)
{
--
1.7.0.4
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