This is RFC patch to show how NVDIMM could set a flag on the
MemoryRegion that would be propagated down to the flat view.
This way, guest_phys_blocks_region_add() can skip the NV memory
regions for dumps and TCG memory clear.
qemu-system-x86_64 -machine pc,nvdimm -m 2G,slots=4,maxmem=16G -enable-kvm
-monitor stdio -object
memory-backend-file,id=mem1,share=on,mem-path=/tmp/foo,size=1G -device
nvdimm,id=nvdimm1,memdev=mem1
HMP info mtree command reflects the flag with "nv-" prefix on memory type:
(qemu) info mtree
0000000100000000-000000013fffffff (prio 0, nv-i/o): alias nvdimm-memory
@/objects/mem1 0000000000000000-000000003fffffff
(qemu) info mtree -f
0000000100000000-000000013fffffff (prio 0, nv-ram): /objects/mem1
Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com>
---
include/exec/memory.h | 25 +++++++++++++++++++++++
hw/mem/nvdimm.c | 1 +
memory.c | 43 ++++++++++++++++++++++++++++++----------
memory_mapping.c | 3 ++-
docs/devel/migration.rst | 1 +
5 files changed, 62 insertions(+), 11 deletions(-)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index eb4f2fb249..b334331d3e 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -360,6 +360,7 @@ struct MemoryRegion {
bool ram;
bool subpage;
bool readonly; /* For RAM regions */
+ bool nv; /* For non-volatile regions */
bool rom_device;
bool flush_coalesced_mmio;
bool global_locking;
@@ -485,6 +486,7 @@ static inline FlatView
*address_space_to_flatview(AddressSpace *as)
* @offset_within_address_space: the address of the first byte of the section
* relative to the region's address space
* @readonly: writes to this section are ignored
+ * @nv: this section is non-volatile
*/
struct MemoryRegionSection {
MemoryRegion *mr;
@@ -493,6 +495,7 @@ struct MemoryRegionSection {
Int128 size;
hwaddr offset_within_address_space;
bool readonly;
+ bool nv;
};
/**
@@ -1175,6 +1178,17 @@ static inline bool memory_region_is_rom(MemoryRegion *mr)
return mr->ram && mr->readonly;
}
+/**
+ * memory_region_is_nv: check whether a memory region is non-volatile
+ *
+ * Returns %true is a memory region is non-volatile memory.
+ *
+ * @mr: the memory region being queried
+ */
+static inline bool memory_region_is_nv(MemoryRegion *mr)
+{
+ return mr->nv;
+}
/**
* memory_region_get_fd: Get a file descriptor backing a RAM memory region.
@@ -1346,6 +1360,17 @@ void memory_region_reset_dirty(MemoryRegion *mr, hwaddr
addr,
*/
void memory_region_set_readonly(MemoryRegion *mr, bool readonly);
+/**
+ * memory_region_set_nv: Turn a memory region non-volatile
+ *
+ * Allows a memory region to be marked as non-volatile.
+ * only useful on RAM regions.
+ *
+ * @mr: the region being updated.
+ * @nv: whether rhe region is to be NV.
+ */
+void memory_region_set_nv(MemoryRegion *mr, bool nv);
+
/**
* memory_region_rom_device_set_romd: enable/disable ROMD mode
*
diff --git a/hw/mem/nvdimm.c b/hw/mem/nvdimm.c
index 1c6674c4ed..016a9fbbb4 100644
--- a/hw/mem/nvdimm.c
+++ b/hw/mem/nvdimm.c
@@ -115,6 +115,7 @@ static void nvdimm_prepare_memory_region(NVDIMMDevice
*nvdimm, Error **errp)
nvdimm->nvdimm_mr = g_new(MemoryRegion, 1);
memory_region_init_alias(nvdimm->nvdimm_mr, OBJECT(dimm),
"nvdimm-memory", mr, 0, pmem_size);
+ memory_region_set_nv(nvdimm->nvdimm_mr, true);
nvdimm->nvdimm_mr->align = align;
}
diff --git a/memory.c b/memory.c
index 9b73892768..8b34a1a077 100644
--- a/memory.c
+++ b/memory.c
@@ -216,6 +216,7 @@ struct FlatRange {
uint8_t dirty_log_mask;
bool romd_mode;
bool readonly;
+ bool nv;
};
#define FOR_EACH_FLAT_RANGE(var, view) \
@@ -231,6 +232,7 @@ section_from_flat_range(FlatRange *fr, FlatView *fv)
.size = fr->addr.size,
.offset_within_address_space = int128_get64(fr->addr.start),
.readonly = fr->readonly,
+ .nv = fr->nv,
};
}
@@ -240,7 +242,8 @@ static bool flatrange_equal(FlatRange *a, FlatRange *b)
&& addrrange_equal(a->addr, b->addr)
&& a->offset_in_region == b->offset_in_region
&& a->romd_mode == b->romd_mode
- && a->readonly == b->readonly;
+ && a->readonly == b->readonly
+ && a->nv == b->nv;
}
static FlatView *flatview_new(MemoryRegion *mr_root)
@@ -312,7 +315,8 @@ static bool can_merge(FlatRange *r1, FlatRange *r2)
int128_make64(r2->offset_in_region))
&& r1->dirty_log_mask == r2->dirty_log_mask
&& r1->romd_mode == r2->romd_mode
- && r1->readonly == r2->readonly;
+ && r1->readonly == r2->readonly
+ && r1->nv == r2->nv;
}
/* Attempt to simplify a view by merging adjacent ranges */
@@ -619,7 +623,8 @@ static void render_memory_region(FlatView *view,
MemoryRegion *mr,
Int128 base,
AddrRange clip,
- bool readonly)
+ bool readonly,
+ bool nv)
{
MemoryRegion *subregion;
unsigned i;
@@ -635,6 +640,7 @@ static void render_memory_region(FlatView *view,
int128_addto(&base, int128_make64(mr->addr));
readonly |= mr->readonly;
+ nv |= mr->nv;
tmp = addrrange_make(base, mr->size);
@@ -647,13 +653,13 @@ static void render_memory_region(FlatView *view,
if (mr->alias) {
int128_subfrom(&base, int128_make64(mr->alias->addr));
int128_subfrom(&base, int128_make64(mr->alias_offset));
- render_memory_region(view, mr->alias, base, clip, readonly);
+ render_memory_region(view, mr->alias, base, clip, readonly, nv);
return;
}
/* Render subregions in priority order. */
QTAILQ_FOREACH(subregion, &mr->subregions, subregions_link) {
- render_memory_region(view, subregion, base, clip, readonly);
+ render_memory_region(view, subregion, base, clip, readonly, nv);
}
if (!mr->terminates) {
@@ -668,6 +674,7 @@ static void render_memory_region(FlatView *view,
fr.dirty_log_mask = memory_region_get_dirty_log_mask(mr);
fr.romd_mode = mr->romd_mode;
fr.readonly = readonly;
+ fr.nv = nv;
/* Render the region itself into any gaps left by the current view. */
for (i = 0; i < view->nr && int128_nz(remain); ++i) {
@@ -753,7 +760,8 @@ static FlatView *generate_memory_topology(MemoryRegion *mr)
if (mr) {
render_memory_region(view, mr, int128_zero(),
- addrrange_make(int128_zero(), int128_2_64()),
false);
+ addrrange_make(int128_zero(), int128_2_64()),
+ false, false);
}
flatview_simplify(view);
@@ -2038,6 +2046,16 @@ void memory_region_set_readonly(MemoryRegion *mr, bool
readonly)
}
}
+void memory_region_set_nv(MemoryRegion *mr, bool nv)
+{
+ if (mr->nv != nv) {
+ memory_region_transaction_begin();
+ mr->nv = nv;
+ memory_region_update_pending |= mr->enabled;
+ memory_region_transaction_commit();
+ }
+}
+
void memory_region_rom_device_set_romd(MemoryRegion *mr, bool romd_mode)
{
if (mr->romd_mode != romd_mode) {
@@ -2488,6 +2506,7 @@ static MemoryRegionSection
memory_region_find_rcu(MemoryRegion *mr,
ret.size = range.size;
ret.offset_within_address_space = int128_get64(range.start);
ret.readonly = fr->readonly;
+ ret.nv = fr->nv;
return ret;
}
@@ -2838,10 +2857,11 @@ static void mtree_print_mr(fprintf_function mon_printf,
void *f,
QTAILQ_INSERT_TAIL(alias_print_queue, ml, mrqueue);
}
mon_printf(f, TARGET_FMT_plx "-" TARGET_FMT_plx
- " (prio %d, %s): alias %s @%s " TARGET_FMT_plx
+ " (prio %d, %s%s): alias %s @%s " TARGET_FMT_plx
"-" TARGET_FMT_plx "%s",
cur_start, cur_end,
mr->priority,
+ mr->nv ? "nv-" : "",
memory_region_type((MemoryRegion *)mr),
memory_region_name(mr),
memory_region_name(mr->alias),
@@ -2853,9 +2873,10 @@ static void mtree_print_mr(fprintf_function mon_printf,
void *f,
}
} else {
mon_printf(f,
- TARGET_FMT_plx "-" TARGET_FMT_plx " (prio %d, %s): %s%s",
+ TARGET_FMT_plx "-" TARGET_FMT_plx " (prio %d, %s%s): %s%s",
cur_start, cur_end,
mr->priority,
+ mr->nv ? "nv-" : "",
memory_region_type((MemoryRegion *)mr),
memory_region_name(mr),
mr->enabled ? "" : " [disabled]");
@@ -2940,19 +2961,21 @@ static void mtree_print_flatview(gpointer key, gpointer
value,
mr = range->mr;
if (range->offset_in_region) {
p(f, MTREE_INDENT TARGET_FMT_plx "-"
- TARGET_FMT_plx " (prio %d, %s): %s @" TARGET_FMT_plx,
+ TARGET_FMT_plx " (prio %d, %s%s): %s @" TARGET_FMT_plx,
int128_get64(range->addr.start),
int128_get64(range->addr.start) + MR_SIZE(range->addr.size),
mr->priority,
+ range->nv ? "nv-" : "",
range->readonly ? "rom" : memory_region_type(mr),
memory_region_name(mr),
range->offset_in_region);
} else {
p(f, MTREE_INDENT TARGET_FMT_plx "-"
- TARGET_FMT_plx " (prio %d, %s): %s",
+ TARGET_FMT_plx " (prio %d, %s%s): %s",
int128_get64(range->addr.start),
int128_get64(range->addr.start) + MR_SIZE(range->addr.size),
mr->priority,
+ range->nv ? "nv-" : "",
range->readonly ? "rom" : memory_region_type(mr),
memory_region_name(mr));
}
diff --git a/memory_mapping.c b/memory_mapping.c
index 775466f3a8..d59806f53b 100644
--- a/memory_mapping.c
+++ b/memory_mapping.c
@@ -206,7 +206,8 @@ static void guest_phys_blocks_region_add(MemoryListener
*listener,
/* we only care about RAM */
if (!memory_region_is_ram(section->mr) ||
- memory_region_is_ram_device(section->mr)) {
+ memory_region_is_ram_device(section->mr) ||
+ memory_region_is_nv(section->mr)) {
return;
}
diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst
index 687570754d..1a0a39d500 100644
--- a/docs/devel/migration.rst
+++ b/docs/devel/migration.rst
@@ -435,6 +435,7 @@ Examples of such memory API functions are:
- memory_region_add_subregion()
- memory_region_del_subregion()
- memory_region_set_readonly()
+ - memory_region_set_nv()
- memory_region_set_enabled()
- memory_region_set_address()
- memory_region_set_alias_offset()
--
2.19.0
