From 59bc8d10dc417884a3bc18a092a62e13645ed044 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 13 Oct 2020 16:49:48 -0700 Subject: device-dax/kmem: introduce dax_kmem_range() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Towards removing the mode specific @dax_kmem_res attribute from the generic 'struct dev_dax', and preparing for multi-range support, teach the driver to calculate the hotplug range from the device range. The hotplug range is the trivially calculated memory-block-size aligned version of the device range. Signed-off-by: Dan Williams Signed-off-by: Andrew Morton Cc: David Hildenbrand Cc: Vishal Verma Cc: Dave Hansen Cc: Pavel Tatashin Cc: Brice Goglin Cc: Dave Jiang Cc: Ira Weiny Cc: Jia He Cc: Joao Martins Cc: Jonathan Cameron Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Ard Biesheuvel Cc: Benjamin Herrenschmidt Cc: Ben Skeggs Cc: Bjorn Helgaas Cc: Borislav Petkov Cc: Boris Ostrovsky Cc: Catalin Marinas Cc: Daniel Vetter Cc: David Airlie Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Hulk Robot Cc: Ingo Molnar Cc: Jason Gunthorpe Cc: Jason Yan Cc: Jeff Moyer Cc: "Jérôme Glisse" Cc: Juergen Gross Cc: kernel test robot Cc: Michael Ellerman Cc: Mike Rapoport Cc: Paul Mackerras Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Randy Dunlap Cc: Stefano Stabellini Cc: Thomas Gleixner Cc: Tom Lendacky Cc: Vivek Goyal Cc: Wei Yang Cc: Will Deacon Link: https://lkml.kernel.org/r/160106111109.30709.3173462396758431559.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Linus Torvalds --- drivers/dax/kmem.c | 40 +++++++++++++++++----------------------- 1 file changed, 17 insertions(+), 23 deletions(-) (limited to 'drivers/dax/kmem.c') diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 5bb133df147d..b0d6a99cf12d 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -19,13 +19,20 @@ static const char *kmem_name; /* Set if any memory will remain added when the driver will be unloaded. */ static bool any_hotremove_failed; +static struct range dax_kmem_range(struct dev_dax *dev_dax) +{ + struct range range; + + /* memory-block align the hotplug range */ + range.start = ALIGN(dev_dax->range.start, memory_block_size_bytes()); + range.end = ALIGN_DOWN(dev_dax->range.end + 1, memory_block_size_bytes()) - 1; + return range; +} + int dev_dax_kmem_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); - struct range *range = &dev_dax->range; - resource_size_t kmem_start; - resource_size_t kmem_size; - resource_size_t kmem_end; + struct range range = dax_kmem_range(dev_dax); struct resource *new_res; const char *new_res_name; int numa_node; @@ -44,25 +51,14 @@ int dev_dax_kmem_probe(struct device *dev) return -EINVAL; } - /* Hotplug starting at the beginning of the next block: */ - kmem_start = ALIGN(range->start, memory_block_size_bytes()); - - kmem_size = range_len(range); - /* Adjust the size down to compensate for moving up kmem_start: */ - kmem_size -= kmem_start - range->start; - /* Align the size down to cover only complete blocks: */ - kmem_size &= ~(memory_block_size_bytes() - 1); - kmem_end = kmem_start + kmem_size; - new_res_name = kstrdup(dev_name(dev), GFP_KERNEL); if (!new_res_name) return -ENOMEM; /* Region is permanently reserved if hotremove fails. */ - new_res = request_mem_region(kmem_start, kmem_size, new_res_name); + new_res = request_mem_region(range.start, range_len(&range), new_res_name); if (!new_res) { - dev_warn(dev, "could not reserve region [%pa-%pa]\n", - &kmem_start, &kmem_end); + dev_warn(dev, "could not reserve region [%#llx-%#llx]\n", range.start, range.end); kfree(new_res_name); return -EBUSY; } @@ -96,9 +92,8 @@ int dev_dax_kmem_probe(struct device *dev) static int dev_dax_kmem_remove(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); + struct range range = dax_kmem_range(dev_dax); struct resource *res = dev_dax->dax_kmem_res; - resource_size_t kmem_start = res->start; - resource_size_t kmem_size = resource_size(res); const char *res_name = res->name; int rc; @@ -108,12 +103,11 @@ static int dev_dax_kmem_remove(struct device *dev) * there is no way to hotremove this memory until reboot because device * unbind will succeed even if we return failure. */ - rc = remove_memory(dev_dax->target_node, kmem_start, kmem_size); + rc = remove_memory(dev_dax->target_node, range.start, range_len(&range)); if (rc) { any_hotremove_failed = true; - dev_err(dev, - "DAX region %pR cannot be hotremoved until the next reboot\n", - res); + dev_err(dev, "%#llx-%#llx cannot be hotremoved until the next reboot\n", + range.start, range.end); return rc; } -- cgit v1.2.3