Add support for flush hints and use them in the nd_blk I/O path instead
of the global persistent_sync() whenever we can.
Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: linux-nvdimm@xxxxxxxxxxxx
Cc: linux-acpi@xxxxxxxxxxxxxxx
---
drivers/acpi/nfit.c | 49 +++++++++++++++++++++++++++++++++++++++++++++----
drivers/acpi/nfit.h | 22 ++++++++++++++++++++++
2 files changed, 67 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 22df61968c1c..6cca50d1c690 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -286,9 +286,20 @@ static void *add_table(struct acpi_nfit_desc *acpi_desc, void *table, const void
idt->interleave_index, idt->line_count);
break;
}
- case ACPI_NFIT_TYPE_FLUSH_ADDRESS:
- dev_dbg(dev, "%s: flush\n", __func__);
+ case ACPI_NFIT_TYPE_FLUSH_ADDRESS: {
+ struct nfit_flush *nfit_flush = devm_kzalloc(dev,
+ sizeof(*nfit_flush), GFP_KERNEL);
+ struct acpi_nfit_flush_address *flush = table;
+
+ if (!nfit_flush)
+ return err;
+ INIT_LIST_HEAD(&nfit_flush->list);
+ nfit_flush->flush = flush;
+ list_add_tail(&nfit_flush->list, &acpi_desc->flushes);
+ dev_dbg(dev, "%s: flush_hint handle: %d hint_count: %d\n",
+ __func__, flush->device_handle, flush->hint_count);
break;
+ }
case ACPI_NFIT_TYPE_SMBIOS:
dev_dbg(dev, "%s: smbios\n", __func__);
break;
@@ -338,6 +349,7 @@ static int nfit_mem_add(struct acpi_nfit_desc *acpi_desc,
{
u16 dcr_index = __to_nfit_memdev(nfit_mem)->region_index;
struct nfit_memdev *nfit_memdev;
+ struct nfit_flush *nfit_flush;
struct nfit_dcr *nfit_dcr;
struct nfit_bdw *nfit_bdw;
struct nfit_idt *nfit_idt;
@@ -384,6 +396,7 @@ static int nfit_mem_add(struct acpi_nfit_desc *acpi_desc,
nfit_memdev->memdev->region_index != dcr_index)
continue;
nfit_mem->memdev_bdw = nfit_memdev->memdev;
+
idt_index = nfit_memdev->memdev->interleave_index;
list_for_each_entry(nfit_idt, &acpi_desc->idts, list) {
if (nfit_idt->idt->interleave_index != idt_index)
@@ -391,6 +404,14 @@ static int nfit_mem_add(struct acpi_nfit_desc *acpi_desc,
nfit_mem->idt_bdw = nfit_idt->idt;
break;
}
+
+ list_for_each_entry(nfit_flush, &acpi_desc->flushes, list) {
+ if (nfit_flush->flush->device_handle !=
+ nfit_memdev->memdev->device_handle)
+ continue;
+ nfit_mem->nfit_flush = nfit_flush;
+ break;
+ }
break;
}
@@ -929,7 +950,7 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
/* mmio->base must be mapped uncacheable */
writeq(cmd, mmio->base + offset);
- persistent_sync();
+ nfit_blk->psync(nfit_blk);
/* FIXME: conditionally perform read-back if mandated by firmware */
}
@@ -970,7 +991,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk, void *iobuf,
}
if (write)
- persistent_sync();
+ nfit_blk->psync(nfit_blk);
rc = read_blk_stat(nfit_blk, bw) ? -EIO : 0;
return rc;
@@ -1130,6 +1151,7 @@ static int acpi_nfit_blk_region_enable(struct nd_bus *nd_bus, struct device *dev
struct nd_bus_descriptor *nd_desc = to_nd_desc(nd_bus);
struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
struct nd_blk_region *ndbr = to_nd_blk_region(dev);
+ struct nfit_flush *nfit_flush;
struct nfit_blk_mmio *mmio;
struct nfit_blk *nfit_blk;
struct nfit_mem *nfit_mem;
@@ -1195,6 +1217,24 @@ static int acpi_nfit_blk_region_enable(struct nd_bus *nd_bus, struct device *dev
return rc;
}
+ nfit_flush = nfit_mem->nfit_flush;
+ if (nfit_flush && nfit_flush->flush->hint_count != 0) {
+ struct acpi_nfit_flush_address *flush = nfit_flush->flush;
+ struct resource res;
+
+ res.start = flush->hint_address[0];
+ res.end = flush->hint_address[0] + sizeof(u64) - 1;
+ res.name = dev_name(dev);
+ res.flags = IORESOURCE_MEM;
+
+ /* only need a single hint address. map uncacheable */
+ nfit_blk->flush_hint = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(nfit_blk->flush_hint))
+ return -ENOMEM;
+ nfit_blk->psync = directed_psync;
+ } else
+ nfit_blk->psync = global_psync;
+
if (mmio->line_size == 0)
return 0;
@@ -1349,6 +1389,7 @@ int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, acpi_size sz)
INIT_LIST_HEAD(&acpi_desc->dcrs);
INIT_LIST_HEAD(&acpi_desc->bdws);
INIT_LIST_HEAD(&acpi_desc->idts);
+ INIT_LIST_HEAD(&acpi_desc->flushes);
INIT_LIST_HEAD(&acpi_desc->memdevs);
INIT_LIST_HEAD(&acpi_desc->dimms);
mutex_init(&acpi_desc->spa_map_mutex);
diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h
index b882a22ee7bb..858719017bef 100644
--- a/drivers/acpi/nfit.h
+++ b/drivers/acpi/nfit.h
@@ -18,6 +18,7 @@
#include <linux/libnd.h>
#include <linux/uuid.h>
#include <linux/acpi.h>
+#include <linux/pmem.h>
#include <acpi/acuuid.h>
#define UUID_NFIT_BUS "2f10e7a4-9e91-11e4-89d3-123b93f75cba"
@@ -66,6 +67,11 @@ struct nfit_idt {
struct list_head list;
};
+struct nfit_flush {
+ struct acpi_nfit_flush_address *flush;
+ struct list_head list;
+};
+
struct nfit_memdev {
struct acpi_nfit_memory_map *memdev;
struct list_head list;
@@ -83,6 +89,7 @@ struct nfit_mem {
struct acpi_nfit_system_address *spa_bdw;
struct acpi_nfit_interleave *idt_dcr;
struct acpi_nfit_interleave *idt_bdw;
+ struct nfit_flush *nfit_flush;
struct list_head list;
struct acpi_device *adev;
unsigned long dsm_mask;
@@ -94,6 +101,7 @@ struct acpi_nfit_desc {
struct mutex spa_map_mutex;
struct list_head spa_maps;
struct list_head memdevs;
+ struct list_head flushes;
struct list_head dimms;
struct list_head spas;
struct list_head dcrs;
@@ -131,6 +139,8 @@ struct nfit_blk {
u64 bdw_offset; /* post interleave offset */
u64 stat_offset;
u64 cmd_offset;
+ void __iomem *flush_hint;
+ void (*psync)(struct nfit_blk *nfit_blk);
};
struct nfit_spa_mapping {
@@ -158,6 +168,18 @@ static inline struct acpi_nfit_desc *to_acpi_desc(struct nd_bus_descriptor *nd_d
return container_of(nd_desc, struct acpi_nfit_desc, nd_desc);
}
+static inline void directed_psync(struct nfit_blk *nfit_blk)
+{
+ wmb(); /* order previous writes */
+ writeq(1, nfit_blk->flush_hint); /* flush_hint must be mapped UC */
+ wmb(); /* order the write to the flush_hint */
+}
+
+static inline void global_psync(struct nfit_blk *nfit_blk)
+{
+ persistent_sync();
+}
+
const u8 *to_nfit_uuid(enum nfit_uuids id);
int acpi_nfit_init(struct acpi_nfit_desc *nfit, acpi_size sz);
#endif /* __NFIT_H__ */
--
1.9.3
--
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