LinuxLists.cc - add a not device managed memremap

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Subject: [PATCH 1/4] resource: add a not device managed request_free_mem_region variant

Factor out the guts of devm_request_free_mem_region so that we can
implement both a device managed and a manually release version as
tiny wrappers around it.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
---
include/linux/ioport.h | 2 ++
kernel/resource.c | 45 +++++++++++++++++++++++++++++-------------
2 files changed, 33 insertions(+), 14 deletions(-)

diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index 5b6a7121c9f0..7bddddfc76d6 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -297,6 +297,8 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2)

struct resource *devm_request_free_mem_region(struct device *dev,
struct resource *base, unsigned long size);
+struct resource *request_free_mem_region(struct resource *base,
+ unsigned long size, const char *name);

#endif /* __ASSEMBLY__ */
#endif /* _LINUX_IOPORT_H */
diff --git a/kernel/resource.c b/kernel/resource.c
index 7ea4306503c5..74877e9d90ca 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -1644,19 +1644,8 @@ void resource_list_free(struct list_head *head)
EXPORT_SYMBOL(resource_list_free);

#ifdef CONFIG_DEVICE_PRIVATE
-/**
- * devm_request_free_mem_region - find free region for device private memory
- *
- * @dev: device struct to bind the resource to
- * @size: size in bytes of the device memory to add
- * @base: resource tree to look in
- *
- * This function tries to find an empty range of physical address big enough to
- * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
- * memory, which in turn allocates struct pages.
- */
-struct resource *devm_request_free_mem_region(struct device *dev,
- struct resource *base, unsigned long size)
+static struct resource *__request_free_mem_region(struct device *dev,
+ struct resource *base, unsigned long size, const char *name)
{
resource_size_t end, addr;
struct resource *res;
@@ -1670,7 +1659,10 @@ struct resource *devm_request_free_mem_region(struct device *dev,
REGION_DISJOINT)
continue;

- res = devm_request_mem_region(dev, addr, size, dev_name(dev));
+ if (dev)
+ res = devm_request_mem_region(dev, addr, size, name);
+ else
+ res = request_mem_region(addr, size, name);
if (!res)
return ERR_PTR(-ENOMEM);
res->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY;
@@ -1679,7 +1671,32 @@ struct resource *devm_request_free_mem_region(struct device *dev,

return ERR_PTR(-ERANGE);
}
+
+/**
+ * devm_request_free_mem_region - find free region for device private memory
+ *
+ * @dev: device struct to bind the resource to
+ * @size: size in bytes of the device memory to add
+ * @base: resource tree to look in
+ *
+ * This function tries to find an empty range of physical address big enough to
+ * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
+ * memory, which in turn allocates struct pages.
+ */
+struct resource *devm_request_free_mem_region(struct device *dev,
+ struct resource *base, unsigned long size)
+{
+ return __request_free_mem_region(dev, base, size, dev_name(dev));
+}
EXPORT_SYMBOL_GPL(devm_request_free_mem_region);
+
+struct resource *request_free_mem_region(struct resource *base,
+ unsigned long size, const char *name)
+{
+ return __request_free_mem_region(NULL, base, size, name);
+}
+EXPORT_SYMBOL_GPL(request_free_mem_region);
+
#endif /* CONFIG_DEVICE_PRIVATE */

static int __init strict_iomem(char *str)
--
2.20.1

2019-08-18 09:13:46

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Subject: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

The dev field in struct dev_pagemap is only used to print dev_name in
two places, which are at best nice to have. Just remove the field
and thus the name in those two messages.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
---
include/linux/memremap.h | 1 -
kernel/memremap.c | 6 +-----
mm/page_alloc.c | 2 +-
3 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index f8a5b2a19945..8f0013e18e14 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -109,7 +109,6 @@ struct dev_pagemap {
struct percpu_ref *ref;
struct percpu_ref internal_ref;
struct completion done;
- struct device *dev;
enum memory_type type;
unsigned int flags;
u64 pci_p2pdma_bus_offset;
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 6ee03a816d67..600a14cbe663 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -96,7 +96,6 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
static void devm_memremap_pages_release(void *data)
{
struct dev_pagemap *pgmap = data;
- struct device *dev = pgmap->dev;
struct resource *res = &pgmap->res;
unsigned long pfn;
int nid;
@@ -123,8 +122,7 @@ static void devm_memremap_pages_release(void *data)

untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res));
pgmap_array_delete(res);
- dev_WARN_ONCE(dev, pgmap->altmap.alloc,
- "%s: failed to free all reserved pages\n", __func__);
+ WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n");
}

static void dev_pagemap_percpu_release(struct percpu_ref *ref)
@@ -245,8 +243,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
goto err_array;
}

- pgmap->dev = dev;
-
error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(res->start),
PHYS_PFN(res->end), pgmap, GFP_KERNEL));
if (error)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 272c6de1bf4e..b39baa2b1faf 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -5982,7 +5982,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
}
}

- pr_info("%s initialised, %lu pages in %ums\n", dev_name(pgmap->dev),
+ pr_info("%s initialised %lu pages in %ums\n", __func__,
size, jiffies_to_msecs(jiffies - start));
}

--
2.20.1

2019-08-18 09:14:08

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Subject: [PATCH 3/4] memremap: don't use a separate devm action for devmap_managed_enable_get

Just clean up for early failures and then piggy back on
devm_memremap_pages_release. This helps with a pending not device
managed version of devm_memremap_pages.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
---
kernel/memremap.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 600a14cbe663..09a087ca30ff 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -21,13 +21,13 @@ DEFINE_STATIC_KEY_FALSE(devmap_managed_key);
EXPORT_SYMBOL(devmap_managed_key);
static atomic_t devmap_managed_enable;

-static void devmap_managed_enable_put(void *data)
+static void devmap_managed_enable_put(void)
{
if (atomic_dec_and_test(&devmap_managed_enable))
static_branch_disable(&devmap_managed_key);
}

-static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap)
+static int devmap_managed_enable_get(struct dev_pagemap *pgmap)
{
if (!pgmap->ops || !pgmap->ops->page_free) {
WARN(1, "Missing page_free method\n");
@@ -36,13 +36,16 @@ static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgm

if (atomic_inc_return(&devmap_managed_enable) == 1)
static_branch_enable(&devmap_managed_key);
- return devm_add_action_or_reset(dev, devmap_managed_enable_put, NULL);
+ return 0;
}
#else
-static int devmap_managed_enable_get(struct device *dev, struct dev_pagemap *pgmap)
+static int devmap_managed_enable_get(struct dev_pagemap *pgmap)
{
return -EINVAL;
}
+static void devmap_managed_enable_put(void)
+{
+}
#endif /* CONFIG_DEV_PAGEMAP_OPS */

static void pgmap_array_delete(struct resource *res)
@@ -123,6 +126,7 @@ static void devm_memremap_pages_release(void *data)
untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res));
pgmap_array_delete(res);
WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n");
+ devmap_managed_enable_put();
}

static void dev_pagemap_percpu_release(struct percpu_ref *ref)
@@ -212,7 +216,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
}

if (need_devmap_managed) {
- error = devmap_managed_enable_get(dev, pgmap);
+ error = devmap_managed_enable_get(pgmap);
if (error)
return ERR_PTR(error);
}
@@ -321,6 +325,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
err_array:
dev_pagemap_kill(pgmap);
dev_pagemap_cleanup(pgmap);
+ devmap_managed_enable_put();
return ERR_PTR(error);
}
EXPORT_SYMBOL_GPL(devm_memremap_pages);
--
2.20.1

2019-08-18 09:14:37

[permalink] [raw]

Subject: [PATCH 4/4] memremap: provide a not device managed memremap_pages

The kvmppc ultravisor code wants a device private memory pool that is
system wide and not attached to a device. Instead of faking up one
provide a low-level memremap_pages for it.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Ira Weiny <[email protected]>
---
include/linux/memremap.h | 2 +
kernel/memremap.c | 84 +++++++++++++++++++++++++---------------
2 files changed, 54 insertions(+), 32 deletions(-)

diff --git a/include/linux/memremap.h b/include/linux/memremap.h
index 8f0013e18e14..fb2a0bd826b9 100644
--- a/include/linux/memremap.h
+++ b/include/linux/memremap.h
@@ -123,6 +123,8 @@ static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap)
}

#ifdef CONFIG_ZONE_DEVICE
+void *memremap_pages(struct dev_pagemap *pgmap, int nid);
+void memunmap_pages(struct dev_pagemap *pgmap);
void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap);
void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap);
struct dev_pagemap *get_dev_pagemap(unsigned long pfn,
diff --git a/kernel/memremap.c b/kernel/memremap.c
index 09a087ca30ff..77a77704eb28 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -96,9 +96,8 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
}
}

-static void devm_memremap_pages_release(void *data)
+void memunmap_pages(struct dev_pagemap *pgmap)
{
- struct dev_pagemap *pgmap = data;
struct resource *res = &pgmap->res;
unsigned long pfn;
int nid;
@@ -128,6 +127,12 @@ static void devm_memremap_pages_release(void *data)
WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n");
devmap_managed_enable_put();
}
+EXPORT_SYMBOL_GPL(memunmap_pages);
+
+static void devm_memremap_pages_release(void *data)
+{
+ memunmap_pages(data);
+}

static void dev_pagemap_percpu_release(struct percpu_ref *ref)
{
@@ -137,27 +142,12 @@ static void dev_pagemap_percpu_release(struct percpu_ref *ref)
complete(&pgmap->done);
}

-/**
- * devm_memremap_pages - remap and provide memmap backing for the given resource
- * @dev: hosting device for @res
- * @pgmap: pointer to a struct dev_pagemap
- *
- * Notes:
- * 1/ At a minimum the res and type members of @pgmap must be initialized
- * by the caller before passing it to this function
- *
- * 2/ The altmap field may optionally be initialized, in which case
- * PGMAP_ALTMAP_VALID must be set in pgmap->flags.
- *
- * 3/ The ref field may optionally be provided, in which pgmap->ref must be
- * 'live' on entry and will be killed and reaped at
- * devm_memremap_pages_release() time, or if this routine fails.
- *
- * 4/ res is expected to be a host memory range that could feasibly be
- * treated as a "System RAM" range, i.e. not a device mmio range, but
- * this is not enforced.
+/*
+ * Not device managed version of dev_memremap_pages, undone by
+ * memunmap_pages(). Please use dev_memremap_pages if you have a struct
+ * device available.
*/
-void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
+void *memremap_pages(struct dev_pagemap *pgmap, int nid)
{
struct resource *res = &pgmap->res;
struct dev_pagemap *conflict_pgmap;
@@ -168,7 +158,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
.altmap = pgmap_altmap(pgmap),
};
pgprot_t pgprot = PAGE_KERNEL;
- int error, nid, is_ram;
+ int error, is_ram;
bool need_devmap_managed = true;

switch (pgmap->type) {
@@ -223,7 +213,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)

conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->start), NULL);
if (conflict_pgmap) {
- dev_WARN(dev, "Conflicting mapping in same section\n");
+ WARN(1, "Conflicting mapping in same section\n");
put_dev_pagemap(conflict_pgmap);
error = -ENOMEM;
goto err_array;
@@ -231,7 +221,7 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)

conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->end), NULL);
if (conflict_pgmap) {
- dev_WARN(dev, "Conflicting mapping in same section\n");
+ WARN(1, "Conflicting mapping in same section\n");
put_dev_pagemap(conflict_pgmap);
error = -ENOMEM;
goto err_array;
@@ -252,7 +242,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
if (error)
goto err_array;

- nid = dev_to_node(dev);
if (nid < 0)
nid = numa_mem_id();

@@ -308,12 +297,6 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
PHYS_PFN(res->start),
PHYS_PFN(resource_size(res)), pgmap);
percpu_ref_get_many(pgmap->ref, pfn_end(pgmap) - pfn_first(pgmap));
-
- error = devm_add_action_or_reset(dev, devm_memremap_pages_release,
- pgmap);
- if (error)
- return ERR_PTR(error);
-
return __va(res->start);

err_add_memory:
@@ -328,6 +311,43 @@ void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
devmap_managed_enable_put();
return ERR_PTR(error);
}
+EXPORT_SYMBOL_GPL(memremap_pages);
+
+/**
+ * devm_memremap_pages - remap and provide memmap backing for the given resource
+ * @dev: hosting device for @res
+ * @pgmap: pointer to a struct dev_pagemap
+ *
+ * Notes:
+ * 1/ At a minimum the res and type members of @pgmap must be initialized
+ * by the caller before passing it to this function
+ *
+ * 2/ The altmap field may optionally be initialized, in which case
+ * PGMAP_ALTMAP_VALID must be set in pgmap->flags.
+ *
+ * 3/ The ref field may optionally be provided, in which pgmap->ref must be
+ * 'live' on entry and will be killed and reaped at
+ * devm_memremap_pages_release() time, or if this routine fails.
+ *
+ * 4/ res is expected to be a host memory range that could feasibly be
+ * treated as a "System RAM" range, i.e. not a device mmio range, but
+ * this is not enforced.
+ */
+void *devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap)
+{
+ int error;
+ void *ret;
+
+ ret = memremap_pages(pgmap, dev_to_node(dev));
+ if (IS_ERR(ret))
+ return ret;
+
+ error = devm_add_action_or_reset(dev, devm_memremap_pages_release,
+ pgmap);
+ if (error)
+ return ERR_PTR(error);
+ return ret;
+}
EXPORT_SYMBOL_GPL(devm_memremap_pages);

void devm_memunmap_pages(struct device *dev, struct dev_pagemap *pgmap)
--
2.20.1

2019-08-19 05:29:39

by Bharata B Rao

[permalink] [raw]

Subject: Re: add a not device managed memremap_pages v3

On Sun, Aug 18, 2019 at 11:05:53AM +0200, Christoph Hellwig wrote:
> Hi Dan and Jason,
>
> Bharata has been working on secure page management for kvmppc guests,
> and one I thing I noticed is that he had to fake up a struct device
> just so that it could be passed to the devm_memremap_pages
> instrastructure for device private memory.
>
> This series adds non-device managed versions of the
> devm_request_free_mem_region and devm_memremap_pages functions for
> his use case.

Tested kvmppc ultravisor patchset with migrate_vma changes and this
patchset. (Had to manually patch mm/memremap.c instead of kernel/memremap.c
though)

For the series,

Tested-by: Bharata B Rao <[email protected]>

2019-08-19 06:33:13

[permalink] [raw]

Subject: Re: add a not device managed memremap_pages v3

On Mon, Aug 19, 2019 at 10:57:52AM +0530, Bharata B Rao wrote:
> On Sun, Aug 18, 2019 at 11:05:53AM +0200, Christoph Hellwig wrote:
> > Hi Dan and Jason,
> >
> > Bharata has been working on secure page management for kvmppc guests,
> > and one I thing I noticed is that he had to fake up a struct device
> > just so that it could be passed to the devm_memremap_pages
> > instrastructure for device private memory.
> >
> > This series adds non-device managed versions of the
> > devm_request_free_mem_region and devm_memremap_pages functions for
> > his use case.
>
> Tested kvmppc ultravisor patchset with migrate_vma changes and this
> patchset. (Had to manually patch mm/memremap.c instead of kernel/memremap.c
> though)

Oh. I rebased to the hmm tree, and that didn't have the rename yet.
And I didn't even notice that as git handled it transparently.

2019-08-20 01:31:04

[permalink] [raw]

Subject: Re: [PATCH 1/4] resource: add a not device managed request_free_mem_region variant

On Sun, Aug 18, 2019 at 2:10 AM Christoph Hellwig <[email protected]> wrote:
>
> Factor out the guts of devm_request_free_mem_region so that we can
> implement both a device managed and a manually release version as
> tiny wrappers around it.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Ira Weiny <[email protected]>
> ---
> include/linux/ioport.h | 2 ++
> kernel/resource.c | 45 +++++++++++++++++++++++++++++-------------
> 2 files changed, 33 insertions(+), 14 deletions(-)
>
> diff --git a/include/linux/ioport.h b/include/linux/ioport.h
> index 5b6a7121c9f0..7bddddfc76d6 100644
> --- a/include/linux/ioport.h
> +++ b/include/linux/ioport.h
> @@ -297,6 +297,8 @@ static inline bool resource_overlaps(struct resource *r1, struct resource *r2)
>
> struct resource *devm_request_free_mem_region(struct device *dev,
> struct resource *base, unsigned long size);
> +struct resource *request_free_mem_region(struct resource *base,
> + unsigned long size, const char *name);
>
> #endif /* __ASSEMBLY__ */
> #endif /* _LINUX_IOPORT_H */
> diff --git a/kernel/resource.c b/kernel/resource.c
> index 7ea4306503c5..74877e9d90ca 100644
> --- a/kernel/resource.c
> +++ b/kernel/resource.c
> @@ -1644,19 +1644,8 @@ void resource_list_free(struct list_head *head)
> EXPORT_SYMBOL(resource_list_free);
>
> #ifdef CONFIG_DEVICE_PRIVATE
> -/**
> - * devm_request_free_mem_region - find free region for device private memory
> - *
> - * @dev: device struct to bind the resource to
> - * @size: size in bytes of the device memory to add
> - * @base: resource tree to look in
> - *
> - * This function tries to find an empty range of physical address big enough to
> - * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
> - * memory, which in turn allocates struct pages.
> - */
> -struct resource *devm_request_free_mem_region(struct device *dev,
> - struct resource *base, unsigned long size)
> +static struct resource *__request_free_mem_region(struct device *dev,
> + struct resource *base, unsigned long size, const char *name)
> {
> resource_size_t end, addr;
> struct resource *res;
> @@ -1670,7 +1659,10 @@ struct resource *devm_request_free_mem_region(struct device *dev,
> REGION_DISJOINT)
> continue;
>
> - res = devm_request_mem_region(dev, addr, size, dev_name(dev));
> + if (dev)
> + res = devm_request_mem_region(dev, addr, size, name);
> + else
> + res = request_mem_region(addr, size, name);
> if (!res)
> return ERR_PTR(-ENOMEM);
> res->desc = IORES_DESC_DEVICE_PRIVATE_MEMORY;
> @@ -1679,7 +1671,32 @@ struct resource *devm_request_free_mem_region(struct device *dev,
>
> return ERR_PTR(-ERANGE);
> }
> +
> +/**
> + * devm_request_free_mem_region - find free region for device private memory
> + *
> + * @dev: device struct to bind the resource to
> + * @size: size in bytes of the device memory to add
> + * @base: resource tree to look in
> + *
> + * This function tries to find an empty range of physical address big enough to
> + * contain the new resource, so that it can later be hotplugged as ZONE_DEVICE
> + * memory, which in turn allocates struct pages.
> + */
> +struct resource *devm_request_free_mem_region(struct device *dev,
> + struct resource *base, unsigned long size)
> +{

Previously we would loudly crash if someone passed NULL to
devm_request_free_mem_region(), but now it will silently work and the
result will leak. Perhaps this wants a:

if (!dev)
return NULL;

...to head off those mistakes?

No major heartburn if you keep it as is, you can add:

Reviewed-by: Dan Williams <[email protected]>

2019-08-20 01:46:30

[permalink] [raw]

Subject: Re: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
>
> The dev field in struct dev_pagemap is only used to print dev_name in
> two places, which are at best nice to have. Just remove the field
> and thus the name in those two messages.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Ira Weiny <[email protected]>

Needs the below as well.

/me goes to check if he ever merged the fix to make the unit test
stuff get built by default with COMPILE_TEST [1]. Argh! Nope, didn't
submit it for 5.3-rc1, sorry for the thrash.

You can otherwise add:

Reviewed-by: Dan Williams <[email protected]>

[1]: https://lore.kernel.org/lkml/156097224232.1086847.9463861924683372741.stgit@dwillia2-desk3.amr.corp.intel.com/

---

diff --git a/tools/testing/nvdimm/test/iomap.c
b/tools/testing/nvdimm/test/iomap.c
index cd040b5abffe..3f55f2f99112 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -132,7 +132,6 @@ void *__wrap_devm_memremap_pages(struct device
*dev, struct dev_pagemap *pgmap)
if (!nfit_res)
return devm_memremap_pages(dev, pgmap);

- pgmap->dev = dev;
if (!pgmap->ref) {
if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup))
return ERR_PTR(-EINVAL);

2019-08-20 02:24:26

[permalink] [raw]

Subject: Re: [PATCH 3/4] memremap: don't use a separate devm action for devmap_managed_enable_get

On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
>
> Just clean up for early failures and then piggy back on
> devm_memremap_pages_release. This helps with a pending not device
> managed version of devm_memremap_pages.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Ira Weiny <[email protected]>

Looks good,

Reviewed-by: Dan Williams <[email protected]>

2019-08-20 02:26:20

[permalink] [raw]

Subject: Re: [PATCH 4/4] memremap: provide a not device managed memremap_pages

On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
>
> The kvmppc ultravisor code wants a device private memory pool that is
> system wide and not attached to a device. Instead of faking up one
> provide a low-level memremap_pages for it.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> Reviewed-by: Ira Weiny <[email protected]>

Looks good,

Reviewed-by: Dan Williams <[email protected]>

2019-08-20 02:28:40

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Subject: Re: [PATCH 1/4] resource: add a not device managed request_free_mem_region variant

On Mon, Aug 19, 2019 at 06:28:30PM -0700, Dan Williams wrote:
>
> Previously we would loudly crash if someone passed NULL to
> devm_request_free_mem_region(), but now it will silently work and the
> result will leak. Perhaps this wants a:

We'd still instantly crash due to the dev_name dereference, right?

2019-08-20 04:40:00

[permalink] [raw]

Subject: Re: [PATCH 1/4] resource: add a not device managed request_free_mem_region variant

On Mon, Aug 19, 2019 at 7:26 PM Christoph Hellwig <[email protected]> wrote:
>
> On Mon, Aug 19, 2019 at 06:28:30PM -0700, Dan Williams wrote:
> >
> > Previously we would loudly crash if someone passed NULL to
> > devm_request_free_mem_region(), but now it will silently work and the
> > result will leak. Perhaps this wants a:
>
> We'd still instantly crash due to the dev_name dereference, right?

Whoops, yes.

2019-08-20 13:29:03

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Subject: Re: add a not device managed memremap_pages v3

On Sun, Aug 18, 2019 at 11:05:53AM +0200, Christoph Hellwig wrote:
> Hi Dan and Jason,
>
> Bharata has been working on secure page management for kvmppc guests,
> and one I thing I noticed is that he had to fake up a struct device
> just so that it could be passed to the devm_memremap_pages
> instrastructure for device private memory.
>
> This series adds non-device managed versions of the
> devm_request_free_mem_region and devm_memremap_pages functions for
> his use case.
>
> Changes since v2:
> - improved changelogs that the the v2 changes into account
>
> Changes since v1:
> - don't overload devm_request_free_mem_region
> - export the memremap_pages and munmap_pages as kvmppc can be a module

Looks good, I fixed up the patch with Dan's note and reviewed them as
well.

Applied to hmm.git as requested

Thanks,
Jason

2019-08-20 13:29:19

[permalink] [raw]

Subject: Re: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

On Mon, Aug 19, 2019 at 06:44:02PM -0700, Dan Williams wrote:
> On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
> >
> > The dev field in struct dev_pagemap is only used to print dev_name in
> > two places, which are at best nice to have. Just remove the field
> > and thus the name in those two messages.
> >
> > Signed-off-by: Christoph Hellwig <[email protected]>
> > Reviewed-by: Ira Weiny <[email protected]>
>
> Needs the below as well.
>
> /me goes to check if he ever merged the fix to make the unit test
> stuff get built by default with COMPILE_TEST [1]. Argh! Nope, didn't
> submit it for 5.3-rc1, sorry for the thrash.
>
> You can otherwise add:
>
> Reviewed-by: Dan Williams <[email protected]>
>
> [1]: https://lore.kernel.org/lkml/156097224232.1086847.9463861924683372741.stgit@dwillia2-desk3.amr.corp.intel.com/

Can you get this merged? Do you want it to go with this series?

Jason

2019-08-21 02:59:42

[permalink] [raw]

Subject: Re: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

On Tue, Aug 20, 2019 at 6:27 AM Jason Gunthorpe <[email protected]> wrote:
>
> On Mon, Aug 19, 2019 at 06:44:02PM -0700, Dan Williams wrote:
> > On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
> > >
> > > The dev field in struct dev_pagemap is only used to print dev_name in
> > > two places, which are at best nice to have. Just remove the field
> > > and thus the name in those two messages.
> > >
> > > Signed-off-by: Christoph Hellwig <[email protected]>
> > > Reviewed-by: Ira Weiny <[email protected]>
> >
> > Needs the below as well.
> >
> > /me goes to check if he ever merged the fix to make the unit test
> > stuff get built by default with COMPILE_TEST [1]. Argh! Nope, didn't
> > submit it for 5.3-rc1, sorry for the thrash.
> >
> > You can otherwise add:
> >
> > Reviewed-by: Dan Williams <[email protected]>
> >
> > [1]: https://lore.kernel.org/lkml/156097224232.1086847.9463861924683372741.stgit@dwillia2-desk3.amr.corp.intel.com/
>
> Can you get this merged? Do you want it to go with this series?

Yeah, makes some sense to let you merge it so that you can get
kbuild-robot reports about any follow-on memremap_pages() work that
may trip up the build. Otherwise let me know and I'll get it queued
with the other v5.4 libnvdimm pending bits.

2019-08-21 16:26:09

[permalink] [raw]

Subject: Re: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

On Tue, Aug 20, 2019 at 07:58:22PM -0700, Dan Williams wrote:
> On Tue, Aug 20, 2019 at 6:27 AM Jason Gunthorpe <[email protected]> wrote:
> >
> > On Mon, Aug 19, 2019 at 06:44:02PM -0700, Dan Williams wrote:
> > > On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
> > > >
> > > > The dev field in struct dev_pagemap is only used to print dev_name in
> > > > two places, which are at best nice to have. Just remove the field
> > > > and thus the name in those two messages.
> > > >
> > > > Signed-off-by: Christoph Hellwig <[email protected]>
> > > > Reviewed-by: Ira Weiny <[email protected]>
> > >
> > > Needs the below as well.
> > >
> > > /me goes to check if he ever merged the fix to make the unit test
> > > stuff get built by default with COMPILE_TEST [1]. Argh! Nope, didn't
> > > submit it for 5.3-rc1, sorry for the thrash.
> > >
> > > You can otherwise add:
> > >
> > > Reviewed-by: Dan Williams <[email protected]>
> > >
> > > [1]: https://lore.kernel.org/lkml/156097224232.1086847.9463861924683372741.stgit@dwillia2-desk3.amr.corp.intel.com/
> >
> > Can you get this merged? Do you want it to go with this series?
>
> Yeah, makes some sense to let you merge it so that you can get
> kbuild-robot reports about any follow-on memremap_pages() work that
> may trip up the build. Otherwise let me know and I'll get it queued
> with the other v5.4 libnvdimm pending bits.

Done, I used it already to test build the last series from CH..

Jason

2019-08-22 02:19:48

[permalink] [raw]

Subject: Re: [PATCH 2/4] memremap: remove the dev field in struct dev_pagemap

On Wed, Aug 21, 2019 at 01:24:20PM -0300, Jason Gunthorpe wrote:
> On Tue, Aug 20, 2019 at 07:58:22PM -0700, Dan Williams wrote:
> > On Tue, Aug 20, 2019 at 6:27 AM Jason Gunthorpe <[email protected]> wrote:
> > >
> > > On Mon, Aug 19, 2019 at 06:44:02PM -0700, Dan Williams wrote:
> > > > On Sun, Aug 18, 2019 at 2:12 AM Christoph Hellwig <[email protected]> wrote:
> > > > >
> > > > > The dev field in struct dev_pagemap is only used to print dev_name in
> > > > > two places, which are at best nice to have. Just remove the field
> > > > > and thus the name in those two messages.
> > > > >
> > > > > Signed-off-by: Christoph Hellwig <[email protected]>
> > > > > Reviewed-by: Ira Weiny <[email protected]>
> > > >
> > > > Needs the below as well.
> > > >
> > > > /me goes to check if he ever merged the fix to make the unit test
> > > > stuff get built by default with COMPILE_TEST [1]. Argh! Nope, didn't
> > > > submit it for 5.3-rc1, sorry for the thrash.
> > > >
> > > > You can otherwise add:
> > > >
> > > > Reviewed-by: Dan Williams <[email protected]>
> > > >
> > > > [1]: https://lore.kernel.org/lkml/156097224232.1086847.9463861924683372741.stgit@dwillia2-desk3.amr.corp.intel.com/
> > >
> > > Can you get this merged? Do you want it to go with this series?
> >
> > Yeah, makes some sense to let you merge it so that you can get
> > kbuild-robot reports about any follow-on memremap_pages() work that
> > may trip up the build. Otherwise let me know and I'll get it queued
> > with the other v5.4 libnvdimm pending bits.
>
> Done, I used it already to test build the last series from CH..

It failed 0-day, I'm guessing some missing kconfig stuff

For now I dropped it, but, if you send a v2 I can forward it toward
0-day again!

Thanks,
Jason

2019-08-22 03:48:16