From: Jianpeng Ma <jianpeng.ma@xxxxxxxxx>
This nvm pages allocator will implement the simple buddy to manage the
nvm address space. This patch initializes this buddy for new namespace.
the unit of alloc/free of the buddy is page. DAX device has their
struct page(in dram or PMEM).
struct { /* ZONE_DEVICE pages */
/** @pgmap: Points to the hosting device page map. */
struct dev_pagemap *pgmap;
void *zone_device_data;
/*
* ZONE_DEVICE private pages are counted as being
* mapped so the next 3 words hold the mapping, index,
* and private fields from the source anonymous or
* page cache page while the page is migrated to device
* private memory.
* ZONE_DEVICE MEMORY_DEVICE_FS_DAX pages also
* use the mapping, index, and private fields when
* pmem backed DAX files are mapped.
*/
};
ZONE_DEVICE pages only use pgmap. Other 4 words[16/32 bytes] don't use.
So the second/third word will be used as 'struct list_head ' which list
in buddy. The fourth word(that is normal struct page::index) store pgoff
which the page-offset in the dax device. And the fifth word (that is
normal struct page::private) store order of buddy. page_type will be used
to store buddy flags.
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jianpeng Ma <jianpeng.ma@xxxxxxxxx>
Co-developed-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
Signed-off-by: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
---
drivers/md/bcache/nvm-pages.c | 156 +++++++++++++++++++++++++++++++-
drivers/md/bcache/nvm-pages.h | 6 ++
include/uapi/linux/bcache-nvm.h | 10 +-
3 files changed, 165 insertions(+), 7 deletions(-)
diff --git a/drivers/md/bcache/nvm-pages.c b/drivers/md/bcache/nvm-pages.c
index 34e8a7c8a463..58c28b0779dd 100644
--- a/drivers/md/bcache/nvm-pages.c
+++ b/drivers/md/bcache/nvm-pages.c
@@ -32,6 +32,10 @@ static void release_nvm_namespaces(struct bch_nvm_set *nvm_set)
for (i = 0; i < nvm_set->total_namespaces_nr; i++) {
ns = nvm_set->nss[i];
if (ns) {
+ kvfree(ns->pages_bitmap);
+ if (ns->pgalloc_recs_bitmap)
+ bitmap_free(ns->pgalloc_recs_bitmap);
+
blkdev_put(ns->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXEC);
kfree(ns);
}
@@ -46,17 +50,130 @@ static void release_nvm_set(struct bch_nvm_set *nvm_set)
kfree(nvm_set);
}
+static struct page *nvm_vaddr_to_page(struct bch_nvm_namespace *ns, void *addr)
+{
+ return virt_to_page(addr);
+}
+
+static void *nvm_pgoff_to_vaddr(struct bch_nvm_namespace *ns, pgoff_t pgoff)
+{
+ return ns->kaddr + (pgoff << PAGE_SHIFT);
+}
+
+static inline void remove_owner_space(struct bch_nvm_namespace *ns,
+ pgoff_t pgoff, u64 nr)
+{
+ while (nr > 0) {
+ unsigned int num = nr > UINT_MAX ? UINT_MAX : nr;
+
+ bitmap_set(ns->pages_bitmap, pgoff, num);
+ nr -= num;
+ pgoff += num;
+ }
+}
+
+#define BCH_PGOFF_TO_KVADDR(pgoff) ((void *)((unsigned long)pgoff << PAGE_SHIFT))
+
static int init_owner_info(struct bch_nvm_namespace *ns)
{
struct bch_owner_list_head *owner_list_head = ns->sb->owner_list_head;
+ struct bch_nvm_pgalloc_recs *sys_recs;
+ int i, j, k, rc = 0;
mutex_lock(&only_set->lock);
only_set->owner_list_head = owner_list_head;
only_set->owner_list_size = owner_list_head->size;
only_set->owner_list_used = owner_list_head->used;
+
+ /* remove used space */
+ remove_owner_space(ns, 0, div_u64(ns->pages_offset, ns->page_size));
+
+ sys_recs = ns->kaddr + BCH_NVM_PAGES_SYS_RECS_HEAD_OFFSET;
+ /* suppose no hole in array */
+ for (i = 0; i < owner_list_head->used; i++) {
+ struct bch_nvm_pages_owner_head *head = &owner_list_head->heads[i];
+
+ for (j = 0; j < BCH_NVM_PAGES_NAMESPACES_MAX; j++) {
+ struct bch_nvm_pgalloc_recs *pgalloc_recs = head->recs[j];
+ unsigned long offset = (unsigned long)ns->kaddr >> PAGE_SHIFT;
+ struct page *page;
+
+ while (pgalloc_recs) {
+ u32 pgalloc_recs_pos = (unsigned int)(pgalloc_recs - sys_recs);
+
+ if (memcmp(pgalloc_recs->magic, bch_nvm_pages_pgalloc_magic, 16)) {
+ pr_info("invalid bch_nvm_pages_pgalloc_magic\n");
+ rc = -EINVAL;
+ goto unlock;
+ }
+ if (memcmp(pgalloc_recs->owner_uuid, head->uuid, 16)) {
+ pr_info("invalid owner_uuid in bch_nvm_pgalloc_recs\n");
+ rc = -EINVAL;
+ goto unlock;
+ }
+ if (pgalloc_recs->owner != head) {
+ pr_info("invalid owner in bch_nvm_pgalloc_recs\n");
+ rc = -EINVAL;
+ goto unlock;
+ }
+
+ /* recs array can has hole */
+ for (k = 0; k < pgalloc_recs->size; k++) {
+ struct bch_pgalloc_rec *rec = &pgalloc_recs->recs[k];
+
+ if (rec->pgoff) {
+ BUG_ON(rec->pgoff <= offset);
+
+ /* init struct page: index/private */
+ page = nvm_vaddr_to_page(ns,
+ BCH_PGOFF_TO_KVADDR(rec->pgoff));
+
+ set_page_private(page, rec->order);
+ page->index = rec->pgoff - offset;
+
+ remove_owner_space(ns,
+ rec->pgoff - offset,
+ 1L << rec->order);
+ }
+ }
+ bitmap_set(ns->pgalloc_recs_bitmap, pgalloc_recs_pos, 1);
+ pgalloc_recs = pgalloc_recs->next;
+ }
+ }
+ }
+unlock:
mutex_unlock(&only_set->lock);
- return 0;
+ return rc;
+}
+
+static void init_nvm_free_space(struct bch_nvm_namespace *ns)
+{
+ unsigned int start, end, pages;
+ int i;
+ struct page *page;
+ pgoff_t pgoff_start;
+
+ bitmap_for_each_clear_region(ns->pages_bitmap, start, end, 0, ns->pages_total) {
+ pgoff_start = start;
+ pages = end - start;
+
+ while (pages) {
+ for (i = BCH_MAX_ORDER - 1; i >= 0 ; i--) {
+ if ((pgoff_start % (1L << i) == 0) && (pages >= (1L << i)))
+ break;
+ }
+
+ page = nvm_vaddr_to_page(ns, nvm_pgoff_to_vaddr(ns, pgoff_start));
+ page->index = pgoff_start;
+ set_page_private(page, i);
+ __SetPageBuddy(page);
+ list_add((struct list_head *)&page->zone_device_data, &ns->free_area[i]);
+
+ pgoff_start += 1L << i;
+ pages -= 1L << i;
+ }
+ }
}
static int attach_nvm_set(struct bch_nvm_namespace *ns)
@@ -163,7 +280,7 @@ static int read_nvdimm_meta_super(struct block_device *bdev,
struct bch_nvm_namespace *bch_register_namespace(const char *dev_path)
{
struct bch_nvm_namespace *ns;
- int err;
+ int i, err;
pgoff_t pgoff;
char buf[BDEVNAME_SIZE];
struct block_device *bdev;
@@ -247,18 +364,49 @@ struct bch_nvm_namespace *bch_register_namespace(const char *dev_path)
ns->nvm_set = only_set;
mutex_init(&ns->lock);
+ /*
+ * parameters of bitmap_set/clear are unsigned int.
+ * Given currently size of nvm is far from exceeding this limit,
+ * so only add a WARN_ON message.
+ */
+ WARN_ON(BITS_TO_LONGS(ns->pages_total) > UINT_MAX);
+ ns->pages_bitmap = kvcalloc(BITS_TO_LONGS(ns->pages_total),
+ sizeof(unsigned long), GFP_KERNEL);
+ if (!ns->pages_bitmap) {
+ err = -ENOMEM;
+ goto clear_ns_nr;
+ }
+
+ if (ns->sb->this_namespace_nr == 0) {
+ ns->pgalloc_recs_bitmap = bitmap_zalloc(BCH_MAX_PGALLOC_RECS, GFP_KERNEL);
+ if (ns->pgalloc_recs_bitmap == NULL) {
+ err = -ENOMEM;
+ goto free_pages_bitmap;
+ }
+ }
+
+ for (i = 0; i < BCH_MAX_ORDER; i++)
+ INIT_LIST_HEAD(&ns->free_area[i]);
+
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);
- only_set->nss[ns->sb->this_namespace_nr] = NULL;
- goto free_ns;
+ goto free_recs_bitmap;
}
+ /* init buddy allocator */
+ init_nvm_free_space(ns);
}
kfree(path);
return ns;
+free_recs_bitmap:
+ bitmap_free(ns->pgalloc_recs_bitmap);
+free_pages_bitmap:
+ kvfree(ns->pages_bitmap);
+clear_ns_nr:
+ only_set->nss[ns->sb->this_namespace_nr] = NULL;
free_ns:
kfree(ns);
bdput:
diff --git a/drivers/md/bcache/nvm-pages.h b/drivers/md/bcache/nvm-pages.h
index 87a0d2c46788..e08864af96a0 100644
--- a/drivers/md/bcache/nvm-pages.h
+++ b/drivers/md/bcache/nvm-pages.h
@@ -16,6 +16,7 @@
* to which owner. After reboot from power failure, they will be initialized
* based on nvm pages superblock in NVDIMM device.
*/
+#define BCH_MAX_ORDER 20
struct bch_nvm_namespace {
struct bch_nvm_pages_sb *sb;
void *kaddr;
@@ -27,6 +28,11 @@ struct bch_nvm_namespace {
u64 pages_total;
pfn_t start_pfn;
+ unsigned long *pages_bitmap;
+ struct list_head free_area[BCH_MAX_ORDER];
+
+ unsigned long *pgalloc_recs_bitmap;
+
struct dax_device *dax_dev;
struct block_device *bdev;
struct bch_nvm_set *nvm_set;
diff --git a/include/uapi/linux/bcache-nvm.h b/include/uapi/linux/bcache-nvm.h
index 1d62e9f0d4bf..dce013a90f37 100644
--- a/include/uapi/linux/bcache-nvm.h
+++ b/include/uapi/linux/bcache-nvm.h
@@ -130,11 +130,15 @@ union {
};
};
-#define BCH_MAX_RECS \
- ((sizeof(struct bch_nvm_pgalloc_recs) - \
- offsetof(struct bch_nvm_pgalloc_recs, recs)) / \
+#define BCH_MAX_RECS \
+ ((sizeof(struct bch_nvm_pgalloc_recs) - \
+ offsetof(struct bch_nvm_pgalloc_recs, recs)) / \
sizeof(struct bch_pgalloc_rec))
+#define BCH_MAX_PGALLOC_RECS \
+ ((BCH_NVM_PAGES_OFFSET - BCH_NVM_PAGES_SYS_RECS_HEAD_OFFSET) / \
+ sizeof(struct bch_nvm_pgalloc_recs))
+
struct bch_nvm_pages_owner_head {
unsigned char uuid[16];
unsigned char label[BCH_NVM_PAGES_LABEL_SIZE];
--
2.25.1
