[PATCH v3 20/23] device-dax: Make align a per-device property

Dan Williams
2020-08-01T03:43:12Z

From: Joao Martins <joao.m.martins@oracle.com>

Introduce @align to struct dev_dax.

When creating a new device, we still initialize to the default
dax_region @align. Child devices belonging to a region may wish
to keep a different alignment property instead of a global
region-defined one.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20200716172913.19658-2-joao.m.martins@oracle.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/dax/bus.c | 1 +
drivers/dax/dax-private.h | 1 +
drivers/dax/device.c | 35 +++++++++++++++--------------------
3 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index ffb27964deb2..feca1413481c 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -1215,6 +1215,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)

dev_dax->dax_dev = dax_dev;
dev_dax->target_node = dax_region->target_node;
+ dev_dax->align = dax_region->align;
ida_init(&dev_dax->ida);
kref_get(&dax_region->kref);

diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h
index 13780f62b95e..96ef5a8ae0ba 100644
--- a/drivers/dax/dax-private.h
+++ b/drivers/dax/dax-private.h
@@ -62,6 +62,7 @@ struct dax_mapping {
struct dev_dax {
struct dax_region *region;
struct dax_device *dax_dev;
+ unsigned int align;
int target_node;
int id;
struct ida ida;
diff --git a/drivers/dax/device.c b/drivers/dax/device.c
index 2bfc5c83e3b0..346c7bb8cf06 100644
--- a/drivers/dax/device.c
+++ b/drivers/dax/device.c
@@ -17,7 +17,6 @@
static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
const char *func)
{
- struct dax_region *dax_region = dev_dax->region;
struct device *dev = &dev_dax->dev;
unsigned long mask;

@@ -32,7 +31,7 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma,
return -EINVAL;
}

- mask = dax_region->align - 1;
+ mask = dev_dax->align - 1;
if (vma->vm_start & mask || vma->vm_end & mask) {
dev_info_ratelimited(dev,
"%s: %s: fail, unaligned vma (%#lx - %#lx, %#lx)\n",
@@ -86,13 +85,13 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax,
return VM_FAULT_SIGBUS;

dax_region = dev_dax->region;
- if (dax_region->align > PAGE_SIZE) {
+ if (dev_dax->align > PAGE_SIZE) {
dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
- dax_region->align, fault_size);
+ dev_dax->align, fault_size);
return VM_FAULT_SIGBUS;
}

- if (fault_size != dax_region->align)
+ if (fault_size != dev_dax->align)
return VM_FAULT_SIGBUS;

phys = dax_pgoff_to_phys(dev_dax, vmf->pgoff, PAGE_SIZE);
@@ -120,15 +119,15 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax,
return VM_FAULT_SIGBUS;

dax_region = dev_dax->region;
- if (dax_region->align > PMD_SIZE) {
+ if (dev_dax->align > PMD_SIZE) {
dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
- dax_region->align, fault_size);
+ dev_dax->align, fault_size);
return VM_FAULT_SIGBUS;
}

- if (fault_size < dax_region->align)
+ if (fault_size < dev_dax->align)
return VM_FAULT_SIGBUS;
- else if (fault_size > dax_region->align)
+ else if (fault_size > dev_dax->align)
return VM_FAULT_FALLBACK;

/* if we are outside of the VMA */
@@ -164,15 +163,15 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax,
return VM_FAULT_SIGBUS;

dax_region = dev_dax->region;
- if (dax_region->align > PUD_SIZE) {
+ if (dev_dax->align > PUD_SIZE) {
dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n",
- dax_region->align, fault_size);
+ dev_dax->align, fault_size);
return VM_FAULT_SIGBUS;
}

- if (fault_size < dax_region->align)
+ if (fault_size < dev_dax->align)
return VM_FAULT_SIGBUS;
- else if (fault_size > dax_region->align)
+ else if (fault_size > dev_dax->align)
return VM_FAULT_FALLBACK;

/* if we are outside of the VMA */
@@ -267,9 +266,8 @@ static int dev_dax_split(struct vm_area_struct *vma, unsigned long addr)
{
struct file *filp = vma->vm_file;
struct dev_dax *dev_dax = filp->private_data;
- struct dax_region *dax_region = dev_dax->region;

- if (!IS_ALIGNED(addr, dax_region->align))
+ if (!IS_ALIGNED(addr, dev_dax->align))
return -EINVAL;
return 0;
}
@@ -278,9 +276,8 @@ static unsigned long dev_dax_pagesize(struct vm_area_struct *vma)
{
struct file *filp = vma->vm_file;
struct dev_dax *dev_dax = filp->private_data;
- struct dax_region *dax_region = dev_dax->region;

- return dax_region->align;
+ return dev_dax->align;
}

static const struct vm_operations_struct dax_vm_ops = {
@@ -319,13 +316,11 @@ static unsigned long dax_get_unmapped_area(struct file *filp,
{
unsigned long off, off_end, off_align, len_align, addr_align, align;
struct dev_dax *dev_dax = filp ? filp->private_data : NULL;
- struct dax_region *dax_region;

if (!dev_dax || addr)
goto out;

- dax_region = dev_dax->region;
- align = dax_region->align;
+ align = dev_dax->align;
off = pgoff << PAGE_SHIFT;
off_end = off + len;
off_align = round_up(off, align);