From: "Jérôme Glisse" <jglisse@redhat.com>
To: akpm@linux-foundation.org, <linux-kernel@vger.kernel.org>,
linux-mm@kvack.org
Cc: "John Hubbard" <jhubbard@nvidia.com>,
"Jérôme Glisse" <jglisse@redhat.com>,
"Jatin Kumar" <jakumar@nvidia.com>,
"Mark Hairgrove" <mhairgrove@nvidia.com>,
"Sherry Cheung" <SCheung@nvidia.com>,
"Subhash Gutti" <sgutti@nvidia.com>
Subject: [HMM v13 18/18] mm/hmm/devmem: dummy HMM device as an helper for ZONE_DEVICE memory
Date: Fri, 18 Nov 2016 13:18:27 -0500 [thread overview]
Message-ID: <1479493107-982-19-git-send-email-jglisse@redhat.com> (raw)
In-Reply-To: <1479493107-982-1-git-send-email-jglisse@redhat.com>
This introduce a dummy HMM device class so device driver can use it to
create hmm_device for the sole purpose of registering device memory.
It is usefull to device driver that want to manage multiple physical
device memory under same device umbrella.
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Signed-off-by: Jatin Kumar <jakumar@nvidia.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mark Hairgrove <mhairgrove@nvidia.com>
Signed-off-by: Sherry Cheung <SCheung@nvidia.com>
Signed-off-by: Subhash Gutti <sgutti@nvidia.com>
---
include/linux/hmm.h | 22 ++++++++++++-
mm/hmm.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 116 insertions(+), 1 deletion(-)
diff --git a/include/linux/hmm.h b/include/linux/hmm.h
index ac0b69a..106de1f 100644
--- a/include/linux/hmm.h
+++ b/include/linux/hmm.h
@@ -88,10 +88,10 @@
#if IS_ENABLED(CONFIG_HMM)
+#include <linux/device.h>
#include <linux/memremap.h>
#include <linux/completion.h>
-
struct hmm;
/*
@@ -484,6 +484,26 @@ static inline unsigned long hmm_devmem_page_get_drvdata(struct page *page)
}
+/*
+ * struct hmm_device - fake device to hang device memory onto
+ *
+ * @device: device struct
+ * @minor: device minor number
+ */
+struct hmm_device {
+ struct device device;
+ unsigned minor;
+};
+
+/*
+ * Device driver that want to handle multiple devices memory through a single
+ * fake device can use hmm_device to do so. This is purely an helper and it
+ * is not needed to make use of any HMM functionality.
+ */
+struct hmm_device *hmm_device_new(void);
+void hmm_device_put(struct hmm_device *hmm_device);
+
+
/* Below are for HMM internal use only ! Not to be use by device driver ! */
void hmm_mm_destroy(struct mm_struct *mm);
diff --git a/mm/hmm.c b/mm/hmm.c
index f2ca895..61c3640187 100644
--- a/mm/hmm.c
+++ b/mm/hmm.c
@@ -24,6 +24,7 @@
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mmzone.h>
+#include <linux/module.h>
#include <linux/pagemap.h>
#include <linux/swapops.h>
#include <linux/hugetlb.h>
@@ -1078,3 +1079,97 @@ int hmm_devmem_fault_range(struct hmm_devmem *devmem,
return 0;
}
EXPORT_SYMBOL(hmm_devmem_fault_range);
+
+/*
+ * Device driver that want to handle multiple devices memory through a single
+ * fake device can use hmm_device to do so. This is purely an helper and it
+ * is not needed to make use of any HMM functionality.
+ */
+#define HMM_DEVICE_MAX 256
+
+static DECLARE_BITMAP(hmm_device_mask, HMM_DEVICE_MAX);
+static DEFINE_SPINLOCK(hmm_device_lock);
+static struct class *hmm_device_class;
+static dev_t hmm_device_devt;
+
+static void hmm_device_release(struct device *device)
+{
+ struct hmm_device *hmm_device;
+
+ hmm_device = container_of(device, struct hmm_device, device);
+ spin_lock(&hmm_device_lock);
+ clear_bit(hmm_device->minor, hmm_device_mask);
+ spin_unlock(&hmm_device_lock);
+
+ kfree(hmm_device);
+}
+
+struct hmm_device *hmm_device_new(void)
+{
+ struct hmm_device *hmm_device;
+ int ret;
+
+ hmm_device = kzalloc(sizeof(*hmm_device), GFP_KERNEL);
+ if (!hmm_device)
+ return ERR_PTR(-ENOMEM);
+
+ ret = alloc_chrdev_region(&hmm_device->device.devt,0,1,"hmm_device");
+ if (ret < 0) {
+ kfree(hmm_device);
+ return NULL;
+ }
+
+ spin_lock(&hmm_device_lock);
+ hmm_device->minor=find_first_zero_bit(hmm_device_mask,HMM_DEVICE_MAX);
+ if (hmm_device->minor >= HMM_DEVICE_MAX) {
+ spin_unlock(&hmm_device_lock);
+ kfree(hmm_device);
+ return NULL;
+ }
+ set_bit(hmm_device->minor, hmm_device_mask);
+ spin_unlock(&hmm_device_lock);
+
+ dev_set_name(&hmm_device->device, "hmm_device%d", hmm_device->minor);
+ hmm_device->device.devt = MKDEV(MAJOR(hmm_device_devt),
+ hmm_device->minor);
+ hmm_device->device.release = hmm_device_release;
+ hmm_device->device.class = hmm_device_class;
+ device_initialize(&hmm_device->device);
+
+ return hmm_device;
+}
+EXPORT_SYMBOL(hmm_device_new);
+
+void hmm_device_put(struct hmm_device *hmm_device)
+{
+ put_device(&hmm_device->device);
+}
+EXPORT_SYMBOL(hmm_device_put);
+
+static int __init hmm_init(void)
+{
+ int ret;
+
+ ret = alloc_chrdev_region(&hmm_device_devt, 0,
+ HMM_DEVICE_MAX,
+ "hmm_device");
+ if (ret)
+ return ret;
+
+ hmm_device_class = class_create(THIS_MODULE, "hmm_device");
+ if (IS_ERR(hmm_device_class)) {
+ unregister_chrdev_region(hmm_device_devt, HMM_DEVICE_MAX);
+ return PTR_ERR(hmm_device_class);
+ }
+ return 0;
+}
+
+static void __exit hmm_exit(void)
+{
+ unregister_chrdev_region(hmm_device_devt, HMM_DEVICE_MAX);
+ class_destroy(hmm_device_class);
+}
+
+module_init(hmm_init);
+module_exit(hmm_exit);
+MODULE_LICENSE("GPL");
--
2.4.3
next prev parent reply other threads:[~2016-11-18 17:18 UTC|newest]
Thread overview: 73+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-18 18:18 [HMM v13 00/18] HMM (Heterogeneous Memory Management) v13 Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 01/18] mm/memory/hotplug: convert device parameter bool to set of flags Jérôme Glisse
2016-11-21 0:44 ` Balbir Singh
2016-11-21 4:53 ` Jerome Glisse
2016-11-21 6:57 ` Anshuman Khandual
2016-11-21 12:19 ` Jerome Glisse
2016-11-21 6:41 ` Anshuman Khandual
2016-11-21 12:27 ` Jerome Glisse
2016-11-22 5:35 ` Anshuman Khandual
2016-11-22 14:08 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 02/18] mm/ZONE_DEVICE/unaddressable: add support for un-addressable device memory Jérôme Glisse
2016-11-21 8:06 ` Anshuman Khandual
2016-11-21 12:33 ` Jerome Glisse
2016-11-22 5:15 ` Anshuman Khandual
2016-11-18 18:18 ` [HMM v13 03/18] mm/ZONE_DEVICE/free_hot_cold_page: catch ZONE_DEVICE pages Jérôme Glisse
2016-11-21 8:18 ` Anshuman Khandual
2016-11-21 12:50 ` Jerome Glisse
2016-11-22 4:30 ` Anshuman Khandual
2016-11-18 18:18 ` [HMM v13 04/18] mm/ZONE_DEVICE/free-page: callback when page is freed Jérôme Glisse
2016-11-21 1:49 ` Balbir Singh
2016-11-21 4:57 ` Jerome Glisse
2016-11-21 8:26 ` Anshuman Khandual
2016-11-21 12:34 ` Jerome Glisse
2016-11-22 5:02 ` Anshuman Khandual
2016-11-18 18:18 ` [HMM v13 05/18] mm/ZONE_DEVICE/devmem_pages_remove: allow early removal of device memory Jérôme Glisse
2016-11-21 10:37 ` Anshuman Khandual
2016-11-21 12:39 ` Jerome Glisse
2016-11-22 4:54 ` Anshuman Khandual
2016-11-18 18:18 ` [HMM v13 06/18] mm/ZONE_DEVICE/unaddressable: add special swap for unaddressable Jérôme Glisse
2016-11-21 2:06 ` Balbir Singh
2016-11-21 5:05 ` Jerome Glisse
2016-11-22 2:19 ` Balbir Singh
2016-11-22 13:59 ` Jerome Glisse
2016-11-21 11:10 ` Anshuman Khandual
2016-11-21 10:58 ` Anshuman Khandual
2016-11-21 12:42 ` Jerome Glisse
2016-11-22 4:48 ` Anshuman Khandual
2016-11-24 13:56 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 07/18] mm/ZONE_DEVICE/x86: add support for un-addressable device memory Jérôme Glisse
2016-11-21 2:08 ` Balbir Singh
2016-11-21 5:08 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 08/18] mm/hmm: heterogeneous memory management (HMM for short) Jérôme Glisse
2016-11-21 2:29 ` Balbir Singh
2016-11-21 5:14 ` Jerome Glisse
2016-11-23 4:03 ` Anshuman Khandual
2016-11-27 13:10 ` Jerome Glisse
2016-11-28 2:58 ` Anshuman Khandual
2016-11-28 9:41 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 09/18] mm/hmm/mirror: mirror process address space on device with HMM helpers Jérôme Glisse
2016-11-21 2:42 ` Balbir Singh
2016-11-21 5:18 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 10/18] mm/hmm/mirror: add range lock helper, prevent CPU page table update for the range Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 11/18] mm/hmm/mirror: add range monitor helper, to monitor CPU page table update Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 12/18] mm/hmm/mirror: helper to snapshot CPU page table Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 13/18] mm/hmm/mirror: device page fault handler Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 14/18] mm/hmm/migrate: support un-addressable ZONE_DEVICE page in migration Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 15/18] mm/hmm/migrate: add new boolean copy flag to migratepage() callback Jérôme Glisse
2016-11-18 18:18 ` [HMM v13 16/18] mm/hmm/migrate: new memory migration helper for use with device memory Jérôme Glisse
2016-11-18 19:57 ` Aneesh Kumar K.V
2016-11-18 20:15 ` Jerome Glisse
2016-11-19 14:32 ` Aneesh Kumar K.V
2016-11-19 17:17 ` Jerome Glisse
2016-11-20 18:21 ` Aneesh Kumar K.V
2016-11-20 20:06 ` Jerome Glisse
2016-11-21 3:30 ` Balbir Singh
2016-11-21 5:31 ` Jerome Glisse
2016-11-18 18:18 ` [HMM v13 17/18] mm/hmm/devmem: device driver helper to hotplug ZONE_DEVICE memory Jérôme Glisse
2016-11-18 18:18 ` Jérôme Glisse [this message]
2016-11-19 0:41 ` [HMM v13 00/18] HMM (Heterogeneous Memory Management) v13 John Hubbard
2016-11-19 14:50 ` Aneesh Kumar K.V
2016-11-23 9:16 ` Haggai Eran
2016-11-25 16:16 ` Jerome Glisse
2016-11-27 13:27 ` Haggai Eran
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