This patch define the prototype data structures in memory and initializes
the nvm pages allocator.
The nv address space which is managed by this allocatior can consist of
many nvm namespaces, and some namespaces can compose into one nvm set,
like cache set. For this initial implementation, only one set can be
supported.
The users of this nvm pages allocator need to call regiseter_namespace()
to register the nvdimm device (like /dev/pmemX) into this allocator as
the instance of struct nvm_namespace.
Signed-off-by: Jianpeng Ma <jianpeng.ma@xxxxxxxxx>
Signed-off-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
---
drivers/md/bcache/Kconfig | 6 +
drivers/md/bcache/Makefile | 2 +-
drivers/md/bcache/nvm-pages.c | 337 ++++++++++++++++++++++++++++++++++
drivers/md/bcache/nvm-pages.h | 91 +++++++++
drivers/md/bcache/super.c | 3 +
5 files changed, 438 insertions(+), 1 deletion(-)
create mode 100644 drivers/md/bcache/nvm-pages.c
create mode 100644 drivers/md/bcache/nvm-pages.h
diff --git a/drivers/md/bcache/Kconfig b/drivers/md/bcache/Kconfig
index d1ca4d059c20..fdec9905ef40 100644
--- a/drivers/md/bcache/Kconfig
+++ b/drivers/md/bcache/Kconfig
@@ -35,3 +35,9 @@ config BCACHE_ASYNC_REGISTRATION
device path into this file will returns immediately and the real
registration work is handled in kernel work queue in asynchronous
way.
+
+config BCACHE_NVM_PAGES
+ bool "NVDIMM support for bcache (EXPERIMENTAL)"
+ depends on BCACHE
+ help
+ nvm pages allocator for bcache.
diff --git a/drivers/md/bcache/Makefile b/drivers/md/bcache/Makefile
index 5b87e59676b8..948e5ed2ca66 100644
--- a/drivers/md/bcache/Makefile
+++ b/drivers/md/bcache/Makefile
@@ -4,4 +4,4 @@ obj-$(CONFIG_BCACHE) += bcache.o
bcache-y := alloc.o bset.o btree.o closure.o debug.o extents.o\
io.o journal.o movinggc.o request.o stats.o super.o sysfs.o trace.o\
- util.o writeback.o features.o
+ util.o writeback.o features.o nvm-pages.o
diff --git a/drivers/md/bcache/nvm-pages.c b/drivers/md/bcache/nvm-pages.c
new file mode 100644
index 000000000000..29ee4dbc504d
--- /dev/null
+++ b/drivers/md/bcache/nvm-pages.c
@@ -0,0 +1,337 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/dax.h>
+#include <linux/pfn_t.h>
+#include <linux/libnvdimm.h>
+#include <linux/mm_types.h>
+#include <linux/err.h>
+#include <linux/pagemap.h>
+#include <linux/bitmap.h>
+#include <linux/blkdev.h>
+#include "nvm-pages.h"
+
+struct bch_nvm_set *only_set;
+
+static struct bch_owner_list *alloc_owner_list(const char *owner_uuid,
+ const char *label, int total_namespaces)
+{
+ struct bch_owner_list *owner_list;
+
+ owner_list = kzalloc(sizeof(*owner_list), GFP_KERNEL);
+ if (!owner_list)
+ return NULL;
+
+ owner_list->alloced_recs = kcalloc(total_namespaces,
+ sizeof(struct bch_nvm_alloced_recs *), GFP_KERNEL);
+ if (!owner_list->alloced_recs) {
+ kfree(owner_list);
+ return NULL;
+ }
+
+ if (owner_uuid)
+ memcpy(owner_list->owner_uuid, owner_uuid, 16);
+ if (label)
+ memcpy(owner_list->label, label, NVM_PAGES_LABEL_SIZE);
+
+ return owner_list;
+}
+
+static void release_extents(struct bch_nvm_alloced_recs *extents)
+{
+ struct list_head *list = extents->extent_head.next;
+ struct bch_extent *extent;
+
+ while (list != &extents->extent_head) {
+ extent = container_of(list, struct bch_extent, list);
+ list_del(list);
+ kfree(extent);
+ list = extents->extent_head.next;
+ }
+ kfree(extents);
+}
+
+static void release_owner_info(struct bch_nvm_set *nvm_set)
+{
+ struct bch_owner_list *owner_list;
+ int i, j;
+
+ for (i = 0; i < nvm_set->owner_list_size; i++) {
+ owner_list = nvm_set->owner_lists[i];
+ for (j = 0; j < nvm_set->total_namespaces_nr; j++) {
+ if (owner_list->alloced_recs[j])
+ release_extents(owner_list->alloced_recs[j]);
+ }
+ kfree(owner_list->alloced_recs);
+ kfree(owner_list);
+ }
+ kfree(nvm_set->owner_lists);
+}
+
+static void release_nvm_namespaces(struct bch_nvm_set *nvm_set)
+{
+ int i;
+
+ for (i = 0; i < nvm_set->total_namespaces_nr; i++)
+ kfree(nvm_set->nss[i]);
+
+ kfree(nvm_set->nss);
+}
+
+static void release_nvm_set(struct bch_nvm_set *nvm_set)
+{
+ release_nvm_namespaces(nvm_set);
+ release_owner_info(nvm_set);
+ kfree(nvm_set);
+}
+
+static void *nvm_pgoff_to_vaddr(struct bch_nvm_namespace *ns, pgoff_t pgoff)
+{
+ return ns->kaddr + ns->pages_offset + (pgoff << PAGE_SHIFT);
+}
+
+static int init_owner_info(struct bch_nvm_namespace *ns)
+{
+ struct owner_list_head *owner_list_head;
+ struct nvm_pages_owner_head *owner_head;
+ struct nvm_pgalloc_recs *nvm_pgalloc_recs;
+ struct bch_owner_list *owner_list;
+ struct bch_nvm_alloced_recs *extents;
+ struct bch_extent *extent;
+ u32 i, j, k;
+
+ owner_list_head = (struct owner_list_head *)
+ (ns->kaddr + NVM_PAGES_OWNER_LIST_HEAD_OFFSET);
+
+ mutex_lock(&only_set->lock);
+ only_set->owner_list_size = owner_list_head->size;
+ for (i = 0; i < owner_list_head->size; i++) {
+ owner_head = &owner_list_head->heads[i];
+ owner_list = alloc_owner_list(owner_head->uuid, owner_head->label,
+ only_set->total_namespaces_nr);
+ if (!owner_list) {
+ mutex_unlock(&only_set->lock);
+ return -ENOMEM;
+ }
+
+ for (j = 0; j < only_set->total_namespaces_nr; j++) {
+ if (!only_set->nss[j] || !owner_head->recs[j])
+ continue;
+
+ nvm_pgalloc_recs = (struct nvm_pgalloc_recs *)
+ ((long)owner_head->recs[j] + ns->kaddr);
+
+ extents = kzalloc(sizeof(*extents), GFP_KERNEL);
+ if (!extents) {
+ mutex_unlock(&only_set->lock);
+ return -ENOMEM;
+ }
+
+ extents->ns = only_set->nss[j];
+ INIT_LIST_HEAD(&extents->extent_head);
+ owner_list->alloced_recs[j] = extents;
+
+ do {
+ struct nvm_pgalloc_rec *rec;
+
+ for (k = 0; k < nvm_pgalloc_recs->size; k++) {
+ rec = &nvm_pgalloc_recs->recs[k];
+ extent = kzalloc(sizeof(*extent), GFP_KERNEL);
+ if (!extents) {
+ mutex_unlock(&only_set->lock);
+ return -ENOMEM;
+ }
+ extent->kaddr = nvm_pgoff_to_vaddr(extents->ns, rec->pgoff);
+ extent->nr = rec->nr;
+ list_add_tail(&extent->list, &extents->extent_head);
+
+ extents->ns->free -= rec->nr;
+ }
+ extents->size += nvm_pgalloc_recs->size;
+
+ if (nvm_pgalloc_recs->next)
+ nvm_pgalloc_recs = (struct nvm_pgalloc_recs *)
+ ((long)nvm_pgalloc_recs->next + ns->kaddr);
+ else
+ nvm_pgalloc_recs = NULL;
+ } while (nvm_pgalloc_recs);
+ }
+ only_set->owner_lists[i] = owner_list;
+ owner_list->nvm_set = only_set;
+ }
+ mutex_unlock(&only_set->lock);
+
+ return 0;
+}
+
+static bool dev_dax_supported(struct block_device *bdev)
+{
+ char buf[BDEVNAME_SIZE];
+ struct page *page;
+ struct nvm_pages_sb *sb;
+ bool supported = false;
+
+ page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
+ NVM_PAGES_SB_OFFSET >> PAGE_SHIFT, GFP_KERNEL);
+
+ if (IS_ERR(page))
+ goto err;
+
+ sb = page_address(page);
+ if (!bdev_dax_supported(bdev, sb->page_size))
+ pr_info("DAX can't supported by %s\n", bdevname(bdev, buf));
+ else
+ supported = true;
+
+ put_page(page);
+err:
+ return supported;
+}
+
+static bool attach_nvm_set(struct bch_nvm_namespace *ns)
+{
+ bool rc = true;
+
+ mutex_lock(&only_set->lock);
+ if (only_set->nss) {
+ if (memcmp(ns->sb->set_uuid, only_set->set_uuid, 16)) {
+ pr_info("namespace id does't match nvm set\n");
+ rc = false;
+ goto unlock;
+ }
+
+ if (only_set->nss[ns->sb->this_namespace_nr]) {
+ pr_info("already has the same position(%d) nvm\n",
+ ns->sb->this_namespace_nr);
+ rc = false;
+ goto unlock;
+ }
+ } else {
+ memcpy(only_set->set_uuid, ns->sb->set_uuid, 16);
+ only_set->total_namespaces_nr = ns->sb->total_namespaces_nr;
+ only_set->nss = kcalloc(only_set->total_namespaces_nr,
+ sizeof(struct bch_nvm_namespace *), GFP_KERNEL);
+ only_set->owner_lists = kcalloc(MAX_OWNER_LIST,
+ sizeof(struct nvm_pages_owner_head *), GFP_KERNEL);
+ if (!only_set->nss || !only_set->owner_lists) {
+ pr_info("can't alloc nss or owner_list\n");
+ kfree(only_set->nss);
+ kfree(only_set->owner_lists);
+ rc = false;
+ goto unlock;
+ }
+ }
+
+ only_set->nss[ns->sb->this_namespace_nr] = ns;
+
+unlock:
+ mutex_unlock(&only_set->lock);
+ return rc;
+}
+
+struct bch_nvm_namespace *bch_register_namespace(const char *dev_path)
+{
+ struct bch_nvm_namespace *ns;
+ int err;
+ pgoff_t pgoff;
+ char buf[BDEVNAME_SIZE];
+ struct block_device *bdev;
+
+ bdev = blkdev_get_by_path(dev_path, FMODE_READ|FMODE_WRITE|FMODE_EXEC, NULL);
+ if (IS_ERR(bdev)) {
+ pr_info("get %s error\n", dev_path);
+ return ERR_PTR(PTR_ERR(bdev));
+ }
+
+ err = -EOPNOTSUPP;
+ if (!dev_dax_supported(bdev)) {
+ pr_info("%s don't support DAX\n", bdevname(bdev, buf));
+ goto bdput;
+ }
+
+ err = -EINVAL;
+ if (bdev_dax_pgoff(bdev, 0, PAGE_SIZE, &pgoff)) {
+ pr_info("invalid offset of %s\n", bdevname(bdev, buf));
+ goto bdput;
+ }
+
+ err = -ENOMEM;
+ ns = kmalloc(sizeof(struct bch_nvm_namespace), GFP_KERNEL);
+ if (!ns)
+ goto bdput;
+
+ err = -EINVAL;
+ ns->dax_dev = fs_dax_get_by_bdev(bdev);
+ if (!ns->dax_dev) {
+ pr_info("can't by dax device by %s\n", bdevname(bdev, buf));
+ goto free_ns;
+ }
+
+ if (dax_direct_access(ns->dax_dev, pgoff, 1, &ns->kaddr, &ns->start_pfn) < 0) {
+ pr_info("dax_direct_access error\n");
+ goto free_ns;
+ }
+
+ ns->sb = (struct nvm_pages_sb *)(ns->kaddr + NVM_PAGES_SB_OFFSET);
+ if (ns->sb->total_namespaces_nr != 1) {
+ pr_info("only one nvm device\n");
+ goto free_ns;
+ }
+
+ err = -EEXIST;
+ if (!attach_nvm_set(ns))
+ goto free_ns;
+
+ ns->page_size = ns->sb->page_size;
+ ns->pages_offset = ns->sb->pages_offset;
+ ns->pages_total = ns->sb->pages_total;
+ ns->start_pfn.val += ns->pages_offset >> PAGE_SHIFT;
+ ns->free = ns->pages_total;
+ ns->bdev = bdev;
+ ns->nvm_set = only_set;
+
+ mutex_init(&ns->lock);
+
+ if (ns->sb->this_namespace_nr == 0) {
+ pr_info("only first namespace contain owner info\n");
+ err = init_owner_info(ns);
+ if (err < 0) {
+ pr_info("init_owner_info met error %d\n", err);
+ goto free_ns;
+ }
+ }
+
+ return ns;
+
+free_ns:
+ kfree(ns);
+bdput:
+ bdput(bdev);
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(bch_register_namespace);
+
+int __init bch_nvm_init(void)
+{
+ only_set = kzalloc(sizeof(*only_set), GFP_KERNEL);
+ if (!only_set)
+ return -ENOMEM;
+
+ only_set->total_namespaces_nr = 0;
+ only_set->owner_lists = NULL;
+ only_set->nss = NULL;
+
+ mutex_init(&only_set->lock);
+
+ pr_info("bcache nvm init\n");
+ return 0;
+}
+
+void bch_nvm_exit(void)
+{
+ release_nvm_set(only_set);
+ pr_info("bcache nvm exit\n");
+}
diff --git a/drivers/md/bcache/nvm-pages.h b/drivers/md/bcache/nvm-pages.h
new file mode 100644
index 000000000000..8850d00a4612
--- /dev/null
+++ b/drivers/md/bcache/nvm-pages.h
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _BCACHE_NVM_PAGES_H
+#define _BCACHE_NVM_PAGES_H
+
+#include <linux/bcache-nvm.h>
+
+/*
+ * Bcache NVDIMM in memory data structures
+ */
+
+/*
+ * The following three structures in memory records which page(s) allocated
+ * to which owner. After reboot from power failure, they will be initialized
+ * based on nvm pages superblock in NVDIMM device.
+ */
+struct bch_extent {
+ void *kaddr;
+ u32 nr;
+ struct list_head list;
+};
+
+struct bch_nvm_alloced_recs {
+ u32 size;
+ struct bch_nvm_namespace *ns;
+ struct list_head extent_head;
+};
+
+struct bch_owner_list {
+ u8 owner_uuid[16];
+ char label[NVM_PAGES_LABEL_SIZE];
+
+ struct bch_nvm_set *nvm_set;
+ struct bch_nvm_alloced_recs **alloced_recs;
+};
+
+struct bch_nvm_namespace {
+ void *kaddr;
+
+ u8 uuid[16];
+ u64 free;
+ u32 page_size;
+ u64 pages_offset;
+ u64 pages_total;
+ pfn_t start_pfn;
+
+ struct dax_device *dax_dev;
+ struct block_device *bdev;
+ struct nvm_pages_sb *sb;
+ struct bch_nvm_set *nvm_set;
+
+ struct mutex lock;
+};
+
+/*
+ * A set of namespaces. Currently only one set can be supported.
+ */
+struct bch_nvm_set {
+ u8 set_uuid[16];
+ u32 total_namespaces_nr;
+
+ u32 owner_list_size;
+ struct bch_owner_list **owner_lists;
+
+ struct bch_nvm_namespace **nss;
+
+ struct mutex lock;
+};
+extern struct bch_nvm_set *only_set;
+
+#ifdef CONFIG_BCACHE_NVM_PAGES
+
+struct bch_nvm_namespace *bch_register_namespace(const char *dev_path);
+int bch_nvm_init(void);
+void bch_nvm_exit(void);
+
+#else
+
+static inline struct bch_nvm_namespace *bch_register_namespace(const char *dev_path)
+{
+ return NULL;
+}
+static inline int bch_nvm_init(void)
+{
+ return 0;
+}
+static inline void bch_nvm_exit(void) { }
+
+#endif /* CONFIG_BCACHE_NVM_PAGES */
+
+#endif /* _BCACHE_NVM_PAGES_H */
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 46a00134a36a..77b608efbe55 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -14,6 +14,7 @@
#include "request.h"
#include "writeback.h"
#include "features.h"
+#include "nvm-pages.h"
#include <linux/blkdev.h>
#include <linux/debugfs.h>
@@ -2782,6 +2783,7 @@ static void bcache_exit(void)
{
bch_debug_exit();
bch_request_exit();
+ bch_nvm_exit();
if (bcache_kobj)
kobject_put(bcache_kobj);
if (bcache_wq)
@@ -2861,6 +2863,7 @@ static int __init bcache_init(void)
bch_debug_init();
closure_debug_init();
+ bch_nvm_init();
bcache_is_reboot = false;
--
2.17.1
