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authorLinus Torvalds <torvalds@linux-foundation.org>2020-12-24 12:06:46 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-12-24 12:06:46 -0800
commit64145482d3339d71f58857591d021588040543f4 (patch)
tree73c3efadd308c546d9c56cde34235cdd006dda49 /drivers/virtio
parent58cf05f597b03a8212d9ecf2c79ee046d3ee8ad9 (diff)
parent418eddef050d5f6393c303a94e3173847ab85466 (diff)
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin: - vdpa sim refactoring - virtio mem: Big Block Mode support - misc cleanus, fixes * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (61 commits) vdpa: Use simpler version of ida allocation vdpa: Add missing comment for virtqueue count uapi: virtio_ids: add missing device type IDs from OASIS spec uapi: virtio_ids.h: consistent indentions vhost scsi: fix error return code in vhost_scsi_set_endpoint() virtio_ring: Fix two use after free bugs virtio_net: Fix error code in probe() virtio_ring: Cut and paste bugs in vring_create_virtqueue_packed() tools/virtio: add barrier for aarch64 tools/virtio: add krealloc_array tools/virtio: include asm/bug.h vdpa/mlx5: Use write memory barrier after updating CQ index vdpa: split vdpasim to core and net modules vdpa_sim: split vdpasim_virtqueue's iov field in out_iov and in_iov vdpa_sim: make vdpasim->buffer size configurable vdpa_sim: use kvmalloc to allocate vdpasim->buffer vdpa_sim: set vringh notify callback vdpa_sim: add set_config callback in vdpasim_dev_attr vdpa_sim: add get_config callback in vdpasim_dev_attr vdpa_sim: make 'config' generic and usable for any device type ...
Diffstat (limited to 'drivers/virtio')
-rw-r--r--drivers/virtio/virtio_mem.c1789
-rw-r--r--drivers/virtio/virtio_ring.c8
2 files changed, 1291 insertions, 506 deletions
diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 181e2f18beae..9fc9ec4a25f5 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -27,20 +27,74 @@ static bool unplug_online = true;
module_param(unplug_online, bool, 0644);
MODULE_PARM_DESC(unplug_online, "Try to unplug online memory");
-enum virtio_mem_mb_state {
+static bool force_bbm;
+module_param(force_bbm, bool, 0444);
+MODULE_PARM_DESC(force_bbm,
+ "Force Big Block Mode. Default is 0 (auto-selection)");
+
+static unsigned long bbm_block_size;
+module_param(bbm_block_size, ulong, 0444);
+MODULE_PARM_DESC(bbm_block_size,
+ "Big Block size in bytes. Default is 0 (auto-detection).");
+
+static bool bbm_safe_unplug = true;
+module_param(bbm_safe_unplug, bool, 0444);
+MODULE_PARM_DESC(bbm_safe_unplug,
+ "Use a safe unplug mechanism in BBM, avoiding long/endless loops");
+
+/*
+ * virtio-mem currently supports the following modes of operation:
+ *
+ * * Sub Block Mode (SBM): A Linux memory block spans 2..X subblocks (SB). The
+ * size of a Sub Block (SB) is determined based on the device block size, the
+ * pageblock size, and the maximum allocation granularity of the buddy.
+ * Subblocks within a Linux memory block might either be plugged or unplugged.
+ * Memory is added/removed to Linux MM in Linux memory block granularity.
+ *
+ * * Big Block Mode (BBM): A Big Block (BB) spans 1..X Linux memory blocks.
+ * Memory is added/removed to Linux MM in Big Block granularity.
+ *
+ * The mode is determined automatically based on the Linux memory block size
+ * and the device block size.
+ *
+ * User space / core MM (auto onlining) is responsible for onlining added
+ * Linux memory blocks - and for selecting a zone. Linux Memory Blocks are
+ * always onlined separately, and all memory within a Linux memory block is
+ * onlined to the same zone - virtio-mem relies on this behavior.
+ */
+
+/*
+ * State of a Linux memory block in SBM.
+ */
+enum virtio_mem_sbm_mb_state {
/* Unplugged, not added to Linux. Can be reused later. */
- VIRTIO_MEM_MB_STATE_UNUSED = 0,
+ VIRTIO_MEM_SBM_MB_UNUSED = 0,
/* (Partially) plugged, not added to Linux. Error on add_memory(). */
- VIRTIO_MEM_MB_STATE_PLUGGED,
+ VIRTIO_MEM_SBM_MB_PLUGGED,
/* Fully plugged, fully added to Linux, offline. */
- VIRTIO_MEM_MB_STATE_OFFLINE,
+ VIRTIO_MEM_SBM_MB_OFFLINE,
/* Partially plugged, fully added to Linux, offline. */
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL,
/* Fully plugged, fully added to Linux, online. */
- VIRTIO_MEM_MB_STATE_ONLINE,
+ VIRTIO_MEM_SBM_MB_ONLINE,
/* Partially plugged, fully added to Linux, online. */
- VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL,
- VIRTIO_MEM_MB_STATE_COUNT
+ VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL,
+ VIRTIO_MEM_SBM_MB_COUNT
+};
+
+/*
+ * State of a Big Block (BB) in BBM, covering 1..X Linux memory blocks.
+ */
+enum virtio_mem_bbm_bb_state {
+ /* Unplugged, not added to Linux. Can be reused later. */
+ VIRTIO_MEM_BBM_BB_UNUSED = 0,
+ /* Plugged, not added to Linux. Error on add_memory(). */
+ VIRTIO_MEM_BBM_BB_PLUGGED,
+ /* Plugged and added to Linux. */
+ VIRTIO_MEM_BBM_BB_ADDED,
+ /* All online parts are fake-offline, ready to remove. */
+ VIRTIO_MEM_BBM_BB_FAKE_OFFLINE,
+ VIRTIO_MEM_BBM_BB_COUNT
};
struct virtio_mem {
@@ -51,6 +105,7 @@ struct virtio_mem {
/* Workqueue that processes the plug/unplug requests. */
struct work_struct wq;
+ atomic_t wq_active;
atomic_t config_changed;
/* Virtqueue for guest->host requests. */
@@ -70,27 +125,13 @@ struct virtio_mem {
/* The device block size (for communicating with the device). */
uint64_t device_block_size;
- /* The translated node id. NUMA_NO_NODE in case not specified. */
+ /* The determined node id for all memory of the device. */
int nid;
/* Physical start address of the memory region. */
uint64_t addr;
/* Maximum region size in bytes. */
uint64_t region_size;
- /* The subblock size. */
- uint64_t subblock_size;
- /* The number of subblocks per memory block. */
- uint32_t nb_sb_per_mb;
-
- /* Id of the first memory block of this device. */
- unsigned long first_mb_id;
- /* Id of the last memory block of this device. */
- unsigned long last_mb_id;
- /* Id of the last usable memory block of this device. */
- unsigned long last_usable_mb_id;
- /* Id of the next memory bock to prepare when needed. */
- unsigned long next_mb_id;
-
/* The parent resource for all memory added via this device. */
struct resource *parent_resource;
/*
@@ -99,31 +140,79 @@ struct virtio_mem {
*/
const char *resource_name;
- /* Summary of all memory block states. */
- unsigned long nb_mb_state[VIRTIO_MEM_MB_STATE_COUNT];
-#define VIRTIO_MEM_NB_OFFLINE_THRESHOLD 10
-
- /*
- * One byte state per memory block.
- *
- * Allocated via vmalloc(). When preparing new blocks, resized
- * (alloc+copy+free) when needed (crossing pages with the next mb).
- * (when crossing pages).
- *
- * With 128MB memory blocks, we have states for 512GB of memory in one
- * page.
- */
- uint8_t *mb_state;
-
/*
- * $nb_sb_per_mb bit per memory block. Handled similar to mb_state.
- *
- * With 4MB subblocks, we manage 128GB of memory in one page.
+ * We don't want to add too much memory if it's not getting onlined,
+ * to avoid running OOM. Besides this threshold, we allow to have at
+ * least two offline blocks at a time (whatever is bigger).
*/
- unsigned long *sb_bitmap;
+#define VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD (1024 * 1024 * 1024)
+ atomic64_t offline_size;
+ uint64_t offline_threshold;
+
+ /* If set, the driver is in SBM, otherwise in BBM. */
+ bool in_sbm;
+
+ union {
+ struct {
+ /* Id of the first memory block of this device. */
+ unsigned long first_mb_id;
+ /* Id of the last usable memory block of this device. */
+ unsigned long last_usable_mb_id;
+ /* Id of the next memory bock to prepare when needed. */
+ unsigned long next_mb_id;
+
+ /* The subblock size. */
+ uint64_t sb_size;
+ /* The number of subblocks per Linux memory block. */
+ uint32_t sbs_per_mb;
+
+ /* Summary of all memory block states. */
+ unsigned long mb_count[VIRTIO_MEM_SBM_MB_COUNT];
+
+ /*
+ * One byte state per memory block. Allocated via
+ * vmalloc(). Resized (alloc+copy+free) on demand.
+ *
+ * With 128 MiB memory blocks, we have states for 512
+ * GiB of memory in one 4 KiB page.
+ */
+ uint8_t *mb_states;
+
+ /*
+ * Bitmap: one bit per subblock. Allocated similar to
+ * sbm.mb_states.
+ *
+ * A set bit means the corresponding subblock is
+ * plugged, otherwise it's unblocked.
+ *
+ * With 4 MiB subblocks, we manage 128 GiB of memory
+ * in one 4 KiB page.
+ */
+ unsigned long *sb_states;
+ } sbm;
+
+ struct {
+ /* Id of the first big block of this device. */
+ unsigned long first_bb_id;
+ /* Id of the last usable big block of this device. */
+ unsigned long last_usable_bb_id;
+ /* Id of the next device bock to prepare when needed. */
+ unsigned long next_bb_id;
+
+ /* Summary of all big block states. */
+ unsigned long bb_count[VIRTIO_MEM_BBM_BB_COUNT];
+
+ /* One byte state per big block. See sbm.mb_states. */
+ uint8_t *bb_states;
+
+ /* The block size used for plugging/adding/removing. */
+ uint64_t bb_size;
+ } bbm;
+ };
/*
- * Mutex that protects the nb_mb_state, mb_state, and sb_bitmap.
+ * Mutex that protects the sbm.mb_count, sbm.mb_states,
+ * sbm.sb_states, bbm.bb_count, and bbm.bb_states
*
* When this lock is held the pointers can't change, ONLINE and
* OFFLINE blocks can't change the state and no subblocks will get
@@ -160,6 +249,11 @@ static DEFINE_MUTEX(virtio_mem_mutex);
static LIST_HEAD(virtio_mem_devices);
static void virtio_mem_online_page_cb(struct page *page, unsigned int order);
+static void virtio_mem_fake_offline_going_offline(unsigned long pfn,
+ unsigned long nr_pages);
+static void virtio_mem_fake_offline_cancel_offline(unsigned long pfn,
+ unsigned long nr_pages);
+static void virtio_mem_retry(struct virtio_mem *vm);
/*
* Register a virtio-mem device so it will be considered for the online_page
@@ -213,6 +307,24 @@ static unsigned long virtio_mem_mb_id_to_phys(unsigned long mb_id)
}
/*
+ * Calculate the big block id of a given address.
+ */
+static unsigned long virtio_mem_phys_to_bb_id(struct virtio_mem *vm,
+ uint64_t addr)
+{
+ return addr / vm->bbm.bb_size;
+}
+
+/*
+ * Calculate the physical start address of a given big block id.
+ */
+static uint64_t virtio_mem_bb_id_to_phys(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ return bb_id * vm->bbm.bb_size;
+}
+
+/*
* Calculate the subblock id of a given address.
*/
static unsigned long virtio_mem_phys_to_sb_id(struct virtio_mem *vm,
@@ -221,89 +333,164 @@ static unsigned long virtio_mem_phys_to_sb_id(struct virtio_mem *vm,
const unsigned long mb_id = virtio_mem_phys_to_mb_id(addr);
const unsigned long mb_addr = virtio_mem_mb_id_to_phys(mb_id);
- return (addr - mb_addr) / vm->subblock_size;
+ return (addr - mb_addr) / vm->sbm.sb_size;
+}
+
+/*
+ * Set the state of a big block, taking care of the state counter.
+ */
+static void virtio_mem_bbm_set_bb_state(struct virtio_mem *vm,
+ unsigned long bb_id,
+ enum virtio_mem_bbm_bb_state state)
+{
+ const unsigned long idx = bb_id - vm->bbm.first_bb_id;
+ enum virtio_mem_bbm_bb_state old_state;
+
+ old_state = vm->bbm.bb_states[idx];
+ vm->bbm.bb_states[idx] = state;
+
+ BUG_ON(vm->bbm.bb_count[old_state] == 0);
+ vm->bbm.bb_count[old_state]--;
+ vm->bbm.bb_count[state]++;
+}
+
+/*
+ * Get the state of a big block.
+ */
+static enum virtio_mem_bbm_bb_state virtio_mem_bbm_get_bb_state(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ return vm->bbm.bb_states[bb_id - vm->bbm.first_bb_id];
+}
+
+/*
+ * Prepare the big block state array for the next big block.
+ */
+static int virtio_mem_bbm_bb_states_prepare_next_bb(struct virtio_mem *vm)
+{
+ unsigned long old_bytes = vm->bbm.next_bb_id - vm->bbm.first_bb_id;
+ unsigned long new_bytes = old_bytes + 1;
+ int old_pages = PFN_UP(old_bytes);
+ int new_pages = PFN_UP(new_bytes);
+ uint8_t *new_array;
+
+ if (vm->bbm.bb_states && old_pages == new_pages)
+ return 0;
+
+ new_array = vzalloc(new_pages * PAGE_SIZE);
+ if (!new_array)
+ return -ENOMEM;
+
+ mutex_lock(&vm->hotplug_mutex);
+ if (vm->bbm.bb_states)
+ memcpy(new_array, vm->bbm.bb_states, old_pages * PAGE_SIZE);
+ vfree(vm->bbm.bb_states);
+ vm->bbm.bb_states = new_array;
+ mutex_unlock(&vm->hotplug_mutex);
+
+ return 0;
}
+#define virtio_mem_bbm_for_each_bb(_vm, _bb_id, _state) \
+ for (_bb_id = vm->bbm.first_bb_id; \
+ _bb_id < vm->bbm.next_bb_id && _vm->bbm.bb_count[_state]; \
+ _bb_id++) \
+ if (virtio_mem_bbm_get_bb_state(_vm, _bb_id) == _state)
+
+#define virtio_mem_bbm_for_each_bb_rev(_vm, _bb_id, _state) \
+ for (_bb_id = vm->bbm.next_bb_id - 1; \
+ _bb_id >= vm->bbm.first_bb_id && _vm->bbm.bb_count[_state]; \
+ _bb_id--) \
+ if (virtio_mem_bbm_get_bb_state(_vm, _bb_id) == _state)
+
/*
* Set the state of a memory block, taking care of the state counter.
*/
-static void virtio_mem_mb_set_state(struct virtio_mem *vm, unsigned long mb_id,
- enum virtio_mem_mb_state state)
+static void virtio_mem_sbm_set_mb_state(struct virtio_mem *vm,
+ unsigned long mb_id, uint8_t state)
{
- const unsigned long idx = mb_id - vm->first_mb_id;
- enum virtio_mem_mb_state old_state;
+ const unsigned long idx = mb_id - vm->sbm.first_mb_id;
+ uint8_t old_state;
- old_state = vm->mb_state[idx];
- vm->mb_state[idx] = state;
+ old_state = vm->sbm.mb_states[idx];
+ vm->sbm.mb_states[idx] = state;
- BUG_ON(vm->nb_mb_state[old_state] == 0);
- vm->nb_mb_state[old_state]--;
- vm->nb_mb_state[state]++;
+ BUG_ON(vm->sbm.mb_count[old_state] == 0);
+ vm->sbm.mb_count[old_state]--;
+ vm->sbm.mb_count[state]++;
}
/*
* Get the state of a memory block.
*/
-static enum virtio_mem_mb_state virtio_mem_mb_get_state(struct virtio_mem *vm,
- unsigned long mb_id)
+static uint8_t virtio_mem_sbm_get_mb_state(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- const unsigned long idx = mb_id - vm->first_mb_id;
+ const unsigned long idx = mb_id - vm->sbm.first_mb_id;
- return vm->mb_state[idx];
+ return vm->sbm.mb_states[idx];
}
/*
* Prepare the state array for the next memory block.
*/
-static int virtio_mem_mb_state_prepare_next_mb(struct virtio_mem *vm)
+static int virtio_mem_sbm_mb_states_prepare_next_mb(struct virtio_mem *vm)
{
- unsigned long old_bytes = vm->next_mb_id - vm->first_mb_id + 1;
- unsigned long new_bytes = vm->next_mb_id - vm->first_mb_id + 2;
- int old_pages = PFN_UP(old_bytes);
- int new_pages = PFN_UP(new_bytes);
- uint8_t *new_mb_state;
+ int old_pages = PFN_UP(vm->sbm.next_mb_id - vm->sbm.first_mb_id);
+ int new_pages = PFN_UP(vm->sbm.next_mb_id - vm->sbm.first_mb_id + 1);
+ uint8_t *new_array;
- if (vm->mb_state && old_pages == new_pages)
+ if (vm->sbm.mb_states && old_pages == new_pages)
return 0;
- new_mb_state = vzalloc(new_pages * PAGE_SIZE);
- if (!new_mb_state)
+ new_array = vzalloc(new_pages * PAGE_SIZE);
+ if (!new_array)
return -ENOMEM;
mutex_lock(&vm->hotplug_mutex);
- if (vm->mb_state)
- memcpy(new_mb_state, vm->mb_state, old_pages * PAGE_SIZE);
- vfree(vm->mb_state);
- vm->mb_state = new_mb_state;
+ if (vm->sbm.mb_states)
+ memcpy(new_array, vm->sbm.mb_states, old_pages * PAGE_SIZE);
+ vfree(vm->sbm.mb_states);
+ vm->sbm.mb_states = new_array;
mutex_unlock(&vm->hotplug_mutex);
return 0;
}
-#define virtio_mem_for_each_mb_state(_vm, _mb_id, _state) \
- for (_mb_id = _vm->first_mb_id; \
- _mb_id < _vm->next_mb_id && _vm->nb_mb_state[_state]; \
+#define virtio_mem_sbm_for_each_mb(_vm, _mb_id, _state) \
+ for (_mb_id = _vm->sbm.first_mb_id; \
+ _mb_id < _vm->sbm.next_mb_id && _vm->sbm.mb_count[_state]; \
_mb_id++) \
- if (virtio_mem_mb_get_state(_vm, _mb_id) == _state)
+ if (virtio_mem_sbm_get_mb_state(_vm, _mb_id) == _state)
-#define virtio_mem_for_each_mb_state_rev(_vm, _mb_id, _state) \
- for (_mb_id = _vm->next_mb_id - 1; \
- _mb_id >= _vm->first_mb_id && _vm->nb_mb_state[_state]; \
+#define virtio_mem_sbm_for_each_mb_rev(_vm, _mb_id, _state) \
+ for (_mb_id = _vm->sbm.next_mb_id - 1; \
+ _mb_id >= _vm->sbm.first_mb_id && _vm->sbm.mb_count[_state]; \
_mb_id--) \
- if (virtio_mem_mb_get_state(_vm, _mb_id) == _state)
+ if (virtio_mem_sbm_get_mb_state(_vm, _mb_id) == _state)
+
+/*
+ * Calculate the bit number in the subblock bitmap for the given subblock
+ * inside the given memory block.
+ */
+static int virtio_mem_sbm_sb_state_bit_nr(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id)
+{
+ return (mb_id - vm->sbm.first_mb_id) * vm->sbm.sbs_per_mb + sb_id;
+}
/*
* Mark all selected subblocks plugged.
*
* Will not modify the state of the memory block.
*/
-static void virtio_mem_mb_set_sb_plugged(struct virtio_mem *vm,
- unsigned long mb_id, int sb_id,
- int count)
+static void virtio_mem_sbm_set_sb_plugged(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id,
+ int count)
{
- const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
+ const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
- __bitmap_set(vm->sb_bitmap, bit, count);
+ __bitmap_set(vm->sbm.sb_states, bit, count);
}
/*
@@ -311,105 +498,114 @@ static void virtio_mem_mb_set_sb_plugged(struct virtio_mem *vm,
*
* Will not modify the state of the memory block.
*/
-static void virtio_mem_mb_set_sb_unplugged(struct virtio_mem *vm,
- unsigned long mb_id, int sb_id,
- int count)
+static void virtio_mem_sbm_set_sb_unplugged(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id,
+ int count)
{
- const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
+ const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
- __bitmap_clear(vm->sb_bitmap, bit, count);
+ __bitmap_clear(vm->sbm.sb_states, bit, count);
}
/*
* Test if all selected subblocks are plugged.
*/
-static bool virtio_mem_mb_test_sb_plugged(struct virtio_mem *vm,
- unsigned long mb_id, int sb_id,
- int count)
+static bool virtio_mem_sbm_test_sb_plugged(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id,
+ int count)
{
- const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
+ const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
if (count == 1)
- return test_bit(bit, vm->sb_bitmap);
+ return test_bit(bit, vm->sbm.sb_states);
/* TODO: Helper similar to bitmap_set() */
- return find_next_zero_bit(vm->sb_bitmap, bit + count, bit) >=
+ return find_next_zero_bit(vm->sbm.sb_states, bit + count, bit) >=
bit + count;
}
/*
* Test if all selected subblocks are unplugged.
*/
-static bool virtio_mem_mb_test_sb_unplugged(struct virtio_mem *vm,
- unsigned long mb_id, int sb_id,
- int count)
+static bool virtio_mem_sbm_test_sb_unplugged(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id,
+ int count)
{
- const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb + sb_id;
+ const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, sb_id);
/* TODO: Helper similar to bitmap_set() */
- return find_next_bit(vm->sb_bitmap, bit + count, bit) >= bit + count;
+ return find_next_bit(vm->sbm.sb_states, bit + count, bit) >=
+ bit + count;
}
/*
- * Find the first unplugged subblock. Returns vm->nb_sb_per_mb in case there is
+ * Find the first unplugged subblock. Returns vm->sbm.sbs_per_mb in case there is
* none.
*/
-static int virtio_mem_mb_first_unplugged_sb(struct virtio_mem *vm,
+static int virtio_mem_sbm_first_unplugged_sb(struct virtio_mem *vm,
unsigned long mb_id)
{
- const int bit = (mb_id - vm->first_mb_id) * vm->nb_sb_per_mb;
+ const int bit = virtio_mem_sbm_sb_state_bit_nr(vm, mb_id, 0);
- return find_next_zero_bit(vm->sb_bitmap, bit + vm->nb_sb_per_mb, bit) -
- bit;
+ return find_next_zero_bit(vm->sbm.sb_states,
+ bit + vm->sbm.sbs_per_mb, bit) - bit;
}
/*
* Prepare the subblock bitmap for the next memory block.
*/
-static int virtio_mem_sb_bitmap_prepare_next_mb(struct virtio_mem *vm)
+static int virtio_mem_sbm_sb_states_prepare_next_mb(struct virtio_mem *vm)
{
- const unsigned long old_nb_mb = vm->next_mb_id - vm->first_mb_id;
- const unsigned long old_nb_bits = old_nb_mb * vm->nb_sb_per_mb;
- const unsigned long new_nb_bits = (old_nb_mb + 1) * vm->nb_sb_per_mb;
+ const unsigned long old_nb_mb = vm->sbm.next_mb_id - vm->sbm.first_mb_id;
+ const unsigned long old_nb_bits = old_nb_mb * vm->sbm.sbs_per_mb;
+ const unsigned long new_nb_bits = (old_nb_mb + 1) * vm->sbm.sbs_per_mb;
int old_pages = PFN_UP(BITS_TO_LONGS(old_nb_bits) * sizeof(long));
int new_pages = PFN_UP(BITS_TO_LONGS(new_nb_bits) * sizeof(long));
- unsigned long *new_sb_bitmap, *old_sb_bitmap;
+ unsigned long *new_bitmap, *old_bitmap;
- if (vm->sb_bitmap && old_pages == new_pages)
+ if (vm->sbm.sb_states && old_pages == new_pages)
return 0;
- new_sb_bitmap = vzalloc(new_pages * PAGE_SIZE);
- if (!new_sb_bitmap)
+ new_bitmap = vzalloc(new_pages * PAGE_SIZE);
+ if (!new_bitmap)
return -ENOMEM;
mutex_lock(&vm->hotplug_mutex);
- if (new_sb_bitmap)
- memcpy(new_sb_bitmap, vm->sb_bitmap, old_pages * PAGE_SIZE);
+ if (new_bitmap)
+ memcpy(new_bitmap, vm->sbm.sb_states, old_pages * PAGE_SIZE);
- old_sb_bitmap = vm->sb_bitmap;
- vm->sb_bitmap = new_sb_bitmap;
+ old_bitmap = vm->sbm.sb_states;
+ vm->sbm.sb_states = new_bitmap;
mutex_unlock(&vm->hotplug_mutex);
- vfree(old_sb_bitmap);
+ vfree(old_bitmap);
return 0;
}
/*
- * Try to add a memory block to Linux. This will usually only fail
- * if out of memory.
+ * Test if we could add memory without creating too much offline memory -
+ * to avoid running OOM if memory is getting onlined deferred.
+ */
+static bool virtio_mem_could_add_memory(struct virtio_mem *vm, uint64_t size)
+{
+ if (WARN_ON_ONCE(size > vm->offline_threshold))
+ return false;
+
+ return atomic64_read(&vm->offline_size) + size <= vm->offline_threshold;
+}
+
+/*
+ * Try adding memory to Linux. Will usually only fail if out of memory.
*
* Must not be called with the vm->hotplug_mutex held (possible deadlock with
* onlining code).
*
- * Will not modify the state of the memory block.
+ * Will not modify the state of memory blocks in virtio-mem.
*/
-static int virtio_mem_mb_add(struct virtio_mem *vm, unsigned long mb_id)
+static int virtio_mem_add_memory(struct virtio_mem *vm, uint64_t addr,
+ uint64_t size)
{
- const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id);
- int nid = vm->nid;
-
- if (nid == NUMA_NO_NODE)
- nid = memory_add_physaddr_to_nid(addr);
+ int rc;
/*
* When force-unloading the driver and we still have memory added to
@@ -422,53 +618,155 @@ static int virtio_mem_mb_add(struct virtio_mem *vm, unsigned long mb_id)
return -ENOMEM;
}
- dev_dbg(&vm->vdev->dev, "adding memory block: %lu\n", mb_id);
- return add_memory_driver_managed(nid, addr, memory_block_size_bytes(),
- vm->resource_name,
- MEMHP_MERGE_RESOURCE);
+ dev_dbg(&vm->vdev->dev, "adding memory: 0x%llx - 0x%llx\n", addr,
+ addr + size - 1);
+ /* Memory might get onlined immediately. */
+ atomic64_add(size, &vm->offline_size);
+ rc = add_memory_driver_managed(vm->nid, addr, size, vm->resource_name,
+ MEMHP_MERGE_RESOURCE);
+ if (rc) {
+ atomic64_sub(size, &vm->offline_size);
+ dev_warn(&vm->vdev->dev, "adding memory failed: %d\n", rc);
+ /*
+ * TODO: Linux MM does not properly clean up yet in all cases
+ * where adding of memory failed - especially on -ENOMEM.
+ */
+ }
+ return rc;
+}
+
+/*
+ * See virtio_mem_add_memory(): Try adding a single Linux memory block.
+ */
+static int virtio_mem_sbm_add_mb(struct virtio_mem *vm, unsigned long mb_id)
+{
+ const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id);
+ const uint64_t size = memory_block_size_bytes();
+
+ return virtio_mem_add_memory(vm, addr, size);
+}
+
+/*
+ * See virtio_mem_add_memory(): Try adding a big block.
+ */
+static int virtio_mem_bbm_add_bb(struct virtio_mem *vm, unsigned long bb_id)
+{
+ const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
+ const uint64_t size = vm->bbm.bb_size;
+
+ return virtio_mem_add_memory(vm, addr, size);
}
/*
- * Try to remove a memory block from Linux. Will only fail if the memory block
- * is not offline.
+ * Try removing memory from Linux. Will only fail if memory blocks aren't
+ * offline.
*
* Must not be called with the vm->hotplug_mutex held (possible deadlock with
* onlining code).
*
- * Will not modify the state of the memory block.
+ * Will not modify the state of memory blocks in virtio-mem.
*/
-static int virtio_mem_mb_remove(struct virtio_mem *vm, unsigned long mb_id)
+static int virtio_mem_remove_memory(struct virtio_mem *vm, uint64_t addr,
+ uint64_t size)
+{
+ int rc;
+
+ dev_dbg(&vm->vdev->dev, "removing memory: 0x%llx - 0x%llx\n", addr,
+ addr + size - 1);
+ rc = remove_memory(vm->nid, addr, size);
+ if (!rc) {
+ atomic64_sub(size, &vm->offline_size);
+ /*
+ * We might have freed up memory we can now unplug, retry
+ * immediately instead of waiting.
+ */
+ virtio_mem_retry(vm);
+ } else {
+ dev_dbg(&vm->vdev->dev, "removing memory failed: %d\n", rc);
+ }
+ return rc;
+}
+
+/*
+ * See virtio_mem_remove_memory(): Try removing a single Linux memory block.
+ */
+static int virtio_mem_sbm_remove_mb(struct virtio_mem *vm, unsigned long mb_id)
{
const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id);
- int nid = vm->nid;
+ const uint64_t size = memory_block_size_bytes();
- if (nid == NUMA_NO_NODE)
- nid = memory_add_physaddr_to_nid(addr);
+ return virtio_mem_remove_memory(vm, addr, size);
+}
- dev_dbg(&vm->vdev->dev, "removing memory block: %lu\n", mb_id);
- return remove_memory(nid, addr, memory_block_size_bytes());
+/*
+ * See virtio_mem_remove_memory(): Try to remove all Linux memory blocks covered
+ * by the big block.
+ */
+static int virtio_mem_bbm_remove_bb(struct virtio_mem *vm, unsigned long bb_id)
+{
+ const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
+ const uint64_t size = vm->bbm.bb_size;
+
+ return virtio_mem_remove_memory(vm, addr, size);
}
/*
- * Try to offline and remove a memory block from Linux.
+ * Try offlining and removing memory from Linux.
*
* Must not be called with the vm->hotplug_mutex held (possible deadlock with
* onlining code).
*
- * Will not modify the state of the memory block.
+ * Will not modify the state of memory blocks in virtio-mem.
*/
-static int virtio_mem_mb_offline_and_remove(struct virtio_mem *vm,
- unsigned long mb_id)
+static int virtio_mem_offline_and_remove_memory(struct virtio_mem *vm,
+ uint64_t addr,
+ uint64_t size)
+{
+ int rc;
+
+ dev_dbg(&vm->vdev->dev,
+ "offlining and removing memory: 0x%llx - 0x%llx\n", addr,
+ addr + size - 1);
+
+ rc = offline_and_remove_memory(vm->nid, addr, size);
+ if (!rc) {
+ atomic64_sub(size, &vm->offline_size);
+ /*
+ * We might have freed up memory we can now unplug, retry
+ * immediately instead of waiting.
+ */
+ virtio_mem_retry(vm);
+ } else {
+ dev_dbg(&vm->vdev->dev,
+ "offlining and removing memory failed: %d\n", rc);
+ }
+ return rc;
+}
+
+/*
+ * See virtio_mem_offline_and_remove_memory(): Try offlining and removing
+ * a single Linux memory block.
+ */
+static int virtio_mem_sbm_offline_and_remove_mb(struct virtio_mem *vm,
+ unsigned long mb_id)
{
const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id);
- int nid = vm->nid;
+ const uint64_t size = memory_block_size_bytes();
+
+ return virtio_mem_offline_and_remove_memory(vm, addr, size);
+}
- if (nid == NUMA_NO_NODE)
- nid = memory_add_physaddr_to_nid(addr);
+/*
+ * See virtio_mem_offline_and_remove_memory(): Try to offline and remove a
+ * all Linux memory blocks covered by the big block.
+ */
+static int virtio_mem_bbm_offline_and_remove_bb(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
+ const uint64_t size = vm->bbm.bb_size;
- dev_dbg(&vm->vdev->dev, "offlining and removing memory block: %lu\n",
- mb_id);
- return offline_and_remove_memory(nid, addr, memory_block_size_bytes());
+ return virtio_mem_offline_and_remove_memory(vm, addr, size);
}
/*
@@ -499,31 +797,28 @@ static int virtio_mem_translate_node_id(struct virtio_mem *vm, uint16_t node_id)
* Test if a virtio-mem device overlaps with the given range. Can be called
* from (notifier) callbacks lockless.
*/
-static bool virtio_mem_overlaps_range(struct virtio_mem *vm,
- unsigned long start, unsigned long size)
+static bool virtio_mem_overlaps_range(struct virtio_mem *vm, uint64_t start,
+ uint64_t size)
{
- unsigned long dev_start = virtio_mem_mb_id_to_phys(vm->first_mb_id);
- unsigned long dev_end = virtio_mem_mb_id_to_phys(vm->last_mb_id) +
- memory_block_size_bytes();
-
- return start < dev_end && dev_start < start + size;
+ return start < vm->addr + vm->region_size && vm->addr < start + size;
}
/*
- * Test if a virtio-mem device owns a memory block. Can be called from
+ * Test if a virtio-mem device contains a given range. Can be called from
* (notifier) callbacks lockless.
*/
-static bool virtio_mem_owned_mb(struct virtio_mem *vm, unsigned long mb_id)
+static bool virtio_mem_contains_range(struct virtio_mem *vm, uint64_t start,
+ uint64_t size)
{
- return mb_id >= vm->first_mb_id && mb_id <= vm->last_mb_id;
+ return start >= vm->addr && start + size <= vm->addr + vm->region_size;
}
-static int virtio_mem_notify_going_online(struct virtio_mem *vm,
- unsigned long mb_id)
+static int virtio_mem_sbm_notify_going_online(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- switch (virtio_mem_mb_get_state(vm, mb_id)) {
- case VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL:
- case VIRTIO_MEM_MB_STATE_OFFLINE:
+ switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) {
+ case VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL:
+ case VIRTIO_MEM_SBM_MB_OFFLINE:
return NOTIFY_OK;
default:
break;
@@ -533,108 +828,100 @@ static int virtio_mem_notify_going_online(struct virtio_mem *vm,
return NOTIFY_BAD;
}
-static void virtio_mem_notify_offline(struct virtio_mem *vm,
- unsigned long mb_id)
+static void virtio_mem_sbm_notify_offline(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- switch (virtio_mem_mb_get_state(vm, mb_id)) {
- case VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL:
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL);
+ switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) {
+ case VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL:
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL);
break;
- case VIRTIO_MEM_MB_STATE_ONLINE:
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE);
+ case VIRTIO_MEM_SBM_MB_ONLINE:
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE);
break;
default:
BUG();
break;
}
-
- /*
- * Trigger the workqueue, maybe we can now unplug memory. Also,
- * when we offline and remove a memory block, this will re-trigger
- * us immediately - which is often nice because the removal of
- * the memory block (e.g., memmap) might have freed up memory
- * on other memory blocks we manage.
- */
- virtio_mem_retry(vm);
}
-static void virtio_mem_notify_online(struct virtio_mem *vm, unsigned long mb_id)
+static void virtio_mem_sbm_notify_online(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- unsigned long nb_offline;
-
- switch (virtio_mem_mb_get_state(vm, mb_id)) {
- case VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL:
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL);
+ switch (virtio_mem_sbm_get_mb_state(vm, mb_id)) {
+ case VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL:
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL);
break;
- case VIRTIO_MEM_MB_STATE_OFFLINE:
- virtio_mem_mb_set_state(vm, mb_id, VIRTIO_MEM_MB_STATE_ONLINE);
+ case VIRTIO_MEM_SBM_MB_OFFLINE:
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE);
break;
default:
BUG();
break;
}
- nb_offline = vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE] +
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL];
-
- /* see if we can add new blocks now that we onlined one block */
- if (nb_offline == VIRTIO_MEM_NB_OFFLINE_THRESHOLD - 1)
- virtio_mem_retry(vm);
}
-static void virtio_mem_notify_going_offline(struct virtio_mem *vm,
- unsigned long mb_id)
+static void virtio_mem_sbm_notify_going_offline(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- const unsigned long nr_pages = PFN_DOWN(vm->subblock_size);
- struct page *page;
+ const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size);
unsigned long pfn;
- int sb_id, i;
+ int sb_id;
- for (sb_id = 0; sb_id < vm->nb_sb_per_mb; sb_id++) {
- if (virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id, 1))
+ for (sb_id = 0; sb_id < vm->sbm.sbs_per_mb; sb_id++) {
+ if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1))
continue;
- /*
- * Drop our reference to the pages so the memory can get
- * offlined and add the unplugged pages to the managed
- * page counters (so offlining code can correctly subtract
- * them again).
- */
pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size);
- adjust_managed_page_count(pfn_to_page(pfn), nr_pages);
- for (i = 0; i < nr_pages; i++) {
- page = pfn_to_page(pfn + i);
- if (WARN_ON(!page_ref_dec_and_test(page)))
- dump_page(page, "unplugged page referenced");
- }
+ sb_id * vm->sbm.sb_size);
+ virtio_mem_fake_offline_going_offline(pfn, nr_pages);
}
}
-static void virtio_mem_notify_cancel_offline(struct virtio_mem *vm,
- unsigned long mb_id)
+static void virtio_mem_sbm_notify_cancel_offline(struct virtio_mem *vm,
+ unsigned long mb_id)
{
- const unsigned long nr_pages = PFN_DOWN(vm->subblock_size);
+ const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size);
unsigned long pfn;
- int sb_id, i;
+ int sb_id;
- for (sb_id = 0; sb_id < vm->nb_sb_per_mb; sb_id++) {
- if (virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id, 1))
+ for (sb_id = 0; sb_id < vm->sbm.sbs_per_mb; sb_id++) {
+ if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1))
continue;
- /*
- * Get the reference we dropped when going offline and
- * subtract the unplugged pages from the managed page
- * counters.
- */
pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size);
- adjust_managed_page_count(pfn_to_page(pfn), -nr_pages);
- for (i = 0; i < nr_pages; i++)
- page_ref_inc(pfn_to_page(pfn + i));
+ sb_id * vm->sbm.sb_size);
+ virtio_mem_fake_offline_cancel_offline(pfn, nr_pages);
}
}
+static void virtio_mem_bbm_notify_going_offline(struct virtio_mem *vm,
+ unsigned long bb_id,
+ unsigned long pfn,
+ unsigned long nr_pages)
+{
+ /*
+ * When marked as "fake-offline", all online memory of this device block
+ * is allocated by us. Otherwise, we don't have any memory allocated.
+ */
+ if (virtio_mem_bbm_get_bb_state(vm, bb_id) !=
+ VIRTIO_MEM_BBM_BB_FAKE_OFFLINE)
+ return;
+ virtio_mem_fake_offline_going_offline(pfn, nr_pages);
+}
+
+static void virtio_mem_bbm_notify_cancel_offline(struct virtio_mem *vm,
+ unsigned long bb_id,
+ unsigned long pfn,
+ unsigned long nr_pages)
+{
+ if (virtio_mem_bbm_get_bb_state(vm, bb_id) !=
+ VIRTIO_MEM_BBM_BB_FAKE_OFFLINE)
+ return;
+ virtio_mem_fake_offline_cancel_offline(pfn, nr_pages);
+}
+
/*
* This callback will either be called synchronously from add_memory() or
* asynchronously (e.g., triggered via user space). We have to be careful
@@ -648,20 +935,33 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
struct memory_notify *mhp = arg;
const unsigned long start = PFN_PHYS(mhp->start_pfn);
const unsigned long size = PFN_PHYS(mhp->nr_pages);
- const unsigned long mb_id = virtio_mem_phys_to_mb_id(start);
int rc = NOTIFY_OK;
+ unsigned long id;
if (!virtio_mem_overlaps_range(vm, start, size))
return NOTIFY_DONE;
- /*
- * Memory is onlined/offlined in memory block granularity. We cannot
- * cross virtio-mem device boundaries and memory block boundaries. Bail
- * out if this ever changes.
- */
- if (WARN_ON_ONCE(size != memory_block_size_bytes() ||
- !IS_ALIGNED(start, memory_block_size_bytes())))
- return NOTIFY_BAD;
+ if (vm->in_sbm) {
+ id = virtio_mem_phys_to_mb_id(start);
+ /*
+ * In SBM, we add memory in separate memory blocks - we expect
+ * it to be onlined/offlined in the same granularity. Bail out
+ * if this ever changes.
+ */
+ if (WARN_ON_ONCE(size != memory_block_size_bytes() ||
+ !IS_ALIGNED(start, memory_block_size_bytes())))
+ return NOTIFY_BAD;
+ } else {
+ id = virtio_mem_phys_to_bb_id(vm, start);
+ /*
+ * In BBM, we only care about onlining/offlining happening
+ * within a single big block, we don't care about the
+ * actual granularity as we don't track individual Linux
+ * memory blocks.
+ */
+ if (WARN_ON_ONCE(id != virtio_mem_phys_to_bb_id(vm, start + size - 1)))
+ return NOTIFY_BAD;
+ }
/*
* Avoid circular locking lockdep warnings. We lock the mutex
@@ -680,7 +980,12 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
break;
}
vm->hotplug_active = true;
- virtio_mem_notify_going_offline(vm, mb_id);
+ if (vm->in_sbm)
+ virtio_mem_sbm_notify_going_offline(vm, id);
+ else
+ virtio_mem_bbm_notify_going_offline(vm, id,
+ mhp->start_pfn,
+ mhp->nr_pages);
break;
case MEM_GOING_ONLINE:
mutex_lock(&vm->hotplug_mutex);
@@ -690,22 +995,51 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
break;
}
vm->hotplug_active = true;
- rc = virtio_mem_notify_going_online(vm, mb_id);
+ if (vm->in_sbm)
+ rc = virtio_mem_sbm_notify_going_online(vm, id);
break;
case MEM_OFFLINE:
- virtio_mem_notify_offline(vm, mb_id);
+ if (vm->in_sbm)
+ virtio_mem_sbm_notify_offline(vm, id);
+
+ atomic64_add(size, &vm->offline_size);
+ /*
+ * Trigger the workqueue. Now that we have some offline memory,
+ * maybe we can handle pending unplug requests.
+ */
+ if (!unplug_online)
+ virtio_mem_retry(vm);
+
vm->hotplug_active = false;
mutex_unlock(&vm->hotplug_mutex);
break;
case MEM_ONLINE:
- virtio_mem_notify_online(vm, mb_id);
+ if (vm->in_sbm)
+ virtio_mem_sbm_notify_online(vm, id);
+
+ atomic64_sub(size, &vm->offline_size);
+ /*
+ * Start adding more memory once we onlined half of our
+ * threshold. Don't trigger if it's possibly due to our actipn
+ * (e.g., us adding memory which gets onlined immediately from
+ * the core).
+ */
+ if (!atomic_read(&vm->wq_active) &&
+ virtio_mem_could_add_memory(vm, vm->offline_threshold / 2))
+ virtio_mem_retry(vm);
+
vm->hotplug_active = false;
mutex_unlock(&vm->hotplug_mutex);
break;
case MEM_CANCEL_OFFLINE:
if (!vm->hotplug_active)
break;
- virtio_mem_notify_cancel_offline(vm, mb_id);
+ if (vm->in_sbm)
+ virtio_mem_sbm_notify_cancel_offline(vm, id);
+ else
+ virtio_mem_bbm_notify_cancel_offline(vm, id,
+ mhp->start_pfn,
+ mhp->nr_pages);
vm->hotplug_active = false;
mutex_unlock(&vm->hotplug_mutex);
break;
@@ -729,7 +1063,7 @@ static int virtio_mem_memory_notifier_cb(struct notifier_block *nb,
* (via generic_online_page()) using PageDirty().
*/
static void virtio_mem_set_fake_offline(unsigned long pfn,
- unsigned int nr_pages, bool onlined)
+ unsigned long nr_pages, bool onlined)
{
for (; nr_pages--; pfn++) {
struct page *page = pfn_to_page(pfn);
@@ -748,7 +1082,7 @@ static void virtio_mem_set_fake_offline(unsigned long pfn,
* (via generic_online_page()), clear PageDirty().
*/
static void virtio_mem_clear_fake_offline(unsigned long pfn,
- unsigned int nr_pages, bool onlined)
+ unsigned long nr_pages, bool onlined)
{
for (; nr_pages--; pfn++) {
struct page *page = pfn_to_page(pfn);
@@ -763,16 +1097,17 @@ static void virtio_mem_clear_fake_offline(unsigned long pfn,
* Release a range of fake-offline pages to the buddy, effectively
* fake-onlining them.
*/
-static void virtio_mem_fake_online(unsigned long pfn, unsigned int nr_pages)
+static void virtio_mem_fake_online(unsigned long pfn, unsigned long nr_pages)
{
- const int order = MAX_ORDER - 1;
- int i;
+ const unsigned long max_nr_pages = MAX_ORDER_NR_PAGES;
+ unsigned long i;
/*
- * We are always called with subblock granularity, which is at least
- * aligned to MAX_ORDER - 1.
+ * We are always called at least with MAX_ORDER_NR_PAGES
+ * granularity/alignment (e.g., the way subblocks work). All pages
+ * inside such a block are alike.
*/
- for (i = 0; i < nr_pages; i += 1 << order) {
+ for (i = 0; i < nr_pages; i += max_nr_pages) {
struct page *page = pfn_to_page(pfn + i);
/*
@@ -782,42 +1117,128 @@ static void virtio_mem_fake_online(unsigned long pfn, unsigned int nr_pages)
* alike.
*/
if (PageDirty(page)) {
- virtio_mem_clear_fake_offline(pfn + i, 1 << order,
+ virtio_mem_clear_fake_offline(pfn + i, max_nr_pages,
false);
- generic_online_page(page, order);
+ generic_online_page(page, MAX_ORDER - 1);
} else {
- virtio_mem_clear_fake_offline(pfn + i, 1 << order,
+ virtio_mem_clear_fake_offline(pfn + i, max_nr_pages,
true);
- free_contig_range(pfn + i, 1 << order);
- adjust_managed_page_count(page, 1 << order);
+ free_contig_range(pfn + i, max_nr_pages);
+ adjust_managed_page_count(page, max_nr_pages);
}
}
}
+/*
+ * Try to allocate a range, marking pages fake-offline, effectively
+ * fake-offlining them.
+ */
+static int virtio_mem_fake_offline(unsigned long pfn, unsigned long nr_pages)
+{
+ const bool is_movable = zone_idx(page_zone(pfn_to_page(pfn))) ==
+ ZONE_MOVABLE;
+ int rc, retry_count;
+
+ /*
+ * TODO: We want an alloc_contig_range() mode that tries to allocate
+ * harder (e.g., dealing with temporarily pinned pages, PCP), especially
+ * with ZONE_MOVABLE. So for now, retry a couple of times with
+ * ZONE_MOVABLE before giving up - because that zone is supposed to give
+ * some guarantees.
+ */
+ for (retry_count = 0; retry_count < 5; retry_count++) {
+ rc = alloc_contig_range(pfn, pfn + nr_pages, MIGRATE_MOVABLE,
+ GFP_KERNEL);
+ if (rc == -ENOMEM)
+ /* whoops, out of memory */
+ return rc;
+ else if (rc && !is_movable)
+ break;
+ else if (rc)
+ continue;
+
+ virtio_mem_set_fake_offline(pfn, nr_pages, true);
+ adjust_managed_page_count(pfn_to_page(pfn), -nr_pages);
+ return 0;
+ }
+
+ return -EBUSY;
+}
+
+/*
+ * Handle fake-offline pages when memory is going offline - such that the
+ * pages can be skipped by mm-core when offlining.
+ */
+static void virtio_mem_fake_offline_going_offline(unsigned long pfn,
+ unsigned long nr_pages)
+{
+ struct page *page;
+ unsigned long i;
+
+ /*
+ * Drop our reference to the pages so the memory can get offlined
+ * and add the unplugged pages to the managed page counters (so
+ * offlining code can correctly subtract them again).
+ */
+ adjust_managed_page_count(pfn_to_page(pfn), nr_pages);
+ /* Drop our reference to the pages so the memory can get offlined. */
+ for (i = 0; i < nr_pages; i++) {
+ page = pfn_to_page(pfn + i);
+ if (WARN_ON(!page_ref_dec_and_test(page)))
+ dump_page(page, "fake-offline page referenced");
+ }
+}
+
+/*
+ * Handle fake-offline pages when memory offlining is canceled - to undo
+ * what we did in virtio_mem_fake_offline_going_offline().
+ */
+static void virtio_mem_fake_offline_cancel_offline(unsigned long pfn,
+ unsigned long nr_pages)
+{
+ unsigned long i;
+
+ /*
+ * Get the reference we dropped when going offline and subtract the
+ * unplugged pages from the managed page counters.
+ */
+ adjust_managed_page_count(pfn_to_page(pfn), -nr_pages);
+ for (i = 0; i < nr_pages; i++)
+ page_ref_inc(pfn_to_page(pfn + i));
+}
+
static void virtio_mem_online_page_cb(struct page *page, unsigned int order)
{
const unsigned long addr = page_to_phys(page);
- const unsigned long mb_id = virtio_mem_phys_to_mb_id(addr);
+ unsigned long id, sb_id;
struct virtio_mem *vm;
- int sb_id;
+ bool do_online;
- /*
- * We exploit here that subblocks have at least MAX_ORDER - 1
- * size/alignment and that this callback is is called with such a
- * size/alignment. So we cannot cross subblocks and therefore
- * also not memory blocks.
- */
rcu_read_lock();
list_for_each_entry_rcu(vm, &virtio_mem_devices, next) {
- if (!virtio_mem_owned_mb(vm, mb_id))
+ if (!virtio_mem_contains_range(vm, addr, PFN_PHYS(1 << order)))
continue;
- sb_id = virtio_mem_phys_to_sb_id(vm, addr);
- /*
- * If plugged, online the pages, otherwise, set them fake
- * offline (PageOffline).
- */
- if (virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id, 1))
+ if (vm->in_sbm) {
+ /*
+ * We exploit here that subblocks have at least
+ * MAX_ORDER_NR_PAGES size/alignment - so we cannot
+ * cross subblocks within one call.
+ */
+ id = virtio_mem_phys_to_mb_id(addr);
+ sb_id = virtio_mem_phys_to_sb_id(vm, addr);
+ do_online = virtio_mem_sbm_test_sb_plugged(vm, id,
+ sb_id, 1);
+ } else {
+ /*
+ * If the whole block is marked fake offline, keep
+ * everything that way.
+ */
+ id = virtio_mem_phys_to_bb_id(vm, addr);
+ do_online = virtio_mem_bbm_get_bb_state(vm, id) !=
+ VIRTIO_MEM_BBM_BB_FAKE_OFFLINE;
+ }
+ if (do_online)
generic_online_page(page, order);
else
virtio_mem_set_fake_offline(PFN_DOWN(addr), 1 << order,
@@ -870,23 +1291,33 @@ static int virtio_mem_send_plug_request(struct virtio_mem *vm, uint64_t addr,
.u.plug.addr = cpu_to_virtio64(vm->vdev, addr),
.u.plug.nb_blocks = cpu_to_virtio16(vm->vdev, nb_vm_blocks),
};
+ int rc = -ENOMEM;
if (atomic_read(&vm->config_changed))
return -EAGAIN;
+ dev_dbg(&vm->vdev->dev, "plugging memory: 0x%llx - 0x%llx\n", addr,
+ addr + size - 1);
+
switch (virtio_mem_send_request(vm, &req)) {
case VIRTIO_MEM_RESP_ACK:
vm->plugged_size += size;
return 0;
case VIRTIO_MEM_RESP_NACK:
- return -EAGAIN;
+ rc = -EAGAIN;
+ break;
case VIRTIO_MEM_RESP_BUSY:
- return -ETXTBSY;
+ rc = -ETXTBSY;
+ break;
case VIRTIO_MEM_RESP_ERROR:
- return -EINVAL;
+ rc = -EINVAL;
+ break;
default:
- return -ENOMEM;
+ break;
}
+
+ dev_dbg(&vm->vdev->dev, "plugging memory failed: %d\n", rc);
+ return rc;
}
static int virtio_mem_send_unplug_request(struct virtio_mem *vm, uint64_t addr,
@@ -898,21 +1329,30 @@ static int virtio_mem_send_unplug_request(struct virtio_mem *vm, uint64_t addr,
.u.unplug.addr = cpu_to_virtio64(vm->vdev, addr),
.u.unplug.nb_blocks = cpu_to_virtio16(vm->vdev, nb_vm_blocks),
};
+ int rc = -ENOMEM;
if (atomic_read(&vm->config_changed))
return -EAGAIN;
+ dev_dbg(&vm->vdev->dev, "unplugging memory: 0x%llx - 0x%llx\n", addr,
+ addr + size - 1);
+
switch (virtio_mem_send_request(vm, &req)) {
case VIRTIO_MEM_RESP_ACK:
vm->plugged_size -= size;
return 0;
case VIRTIO_MEM_RESP_BUSY:
- return -ETXTBSY;
+ rc = -ETXTBSY;
+ break;
case VIRTIO_MEM_RESP_ERROR:
- return -EINVAL;
+ rc = -EINVAL;
+ break;
default:
- return -ENOMEM;
+ break;
}
+
+ dev_dbg(&vm->vdev->dev, "unplugging memory failed: %d\n", rc);
+ return rc;
}
static int virtio_mem_send_unplug_all_request(struct virtio_mem *vm)
@@ -920,6 +1360,9 @@ static int virtio_mem_send_unplug_all_request(struct virtio_mem *vm)
const struct virtio_mem_req req = {
.type = cpu_to_virtio16(vm->vdev, VIRTIO_MEM_REQ_UNPLUG_ALL),
};
+ int rc = -ENOMEM;
+
+ dev_dbg(&vm->vdev->dev, "unplugging all memory");
switch (virtio_mem_send_request(vm, &req)) {
case VIRTIO_MEM_RESP_ACK:
@@ -929,30 +1372,31 @@ static int virtio_mem_send_unplug_all_request(struct virtio_mem *vm)
atomic_set(&vm->config_changed, 1);
return 0;
case VIRTIO_MEM_RESP_BUSY:
- return -ETXTBSY;
+ rc = -ETXTBSY;
+ break;
default:
- return -ENOMEM;
+ break;
}
+
+ dev_dbg(&vm->vdev->dev, "unplugging all memory failed: %d\n", rc);
+ return rc;
}
/*
* Plug selected subblocks. Updates the plugged state, but not the state
* of the memory block.
*/
-static int virtio_mem_mb_plug_sb(struct virtio_mem *vm, unsigned long mb_id,
- int sb_id, int count)
+static int virtio_mem_sbm_plug_sb(struct virtio_mem *vm, unsigned long mb_id,
+ int sb_id, int count)
{
const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size;
- const uint64_t size = count * vm->subblock_size;
+ sb_id * vm->sbm.sb_size;
+ const uint64_t size = count * vm->sbm.sb_size;
int rc;
- dev_dbg(&vm->vdev->dev, "plugging memory block: %lu : %i - %i\n", mb_id,
- sb_id, sb_id + count - 1);
-
rc = virtio_mem_send_plug_request(vm, addr, size);
if (!rc)
- virtio_mem_mb_set_sb_plugged(vm, mb_id, sb_id, count);
+ virtio_mem_sbm_set_sb_plugged(vm, mb_id, sb_id, count);
return rc;
}
@@ -960,24 +1404,47 @@ static int virtio_mem_mb_plug_sb(struct virtio_mem *vm, unsigned long mb_id,
* Unplug selected subblocks. Updates the plugged state, but not the state
* of the memory block.
*/
-static int virtio_mem_mb_unplug_sb(struct virtio_mem *vm, unsigned long mb_id,
- int sb_id, int count)
+static int virtio_mem_sbm_unplug_sb(struct virtio_mem *vm, unsigned long mb_id,
+ int sb_id, int count)
{
const uint64_t addr = virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size;
- const uint64_t size = count * vm->subblock_size;
+ sb_id * vm->sbm.sb_size;
+ const uint64_t size = count * vm->sbm.sb_size;
int rc;
- dev_dbg(&vm->vdev->dev, "unplugging memory block: %lu : %i - %i\n",
- mb_id, sb_id, sb_id + count - 1);
-
rc = virtio_mem_send_unplug_request(vm, addr, size);
if (!rc)
- virtio_mem_mb_set_sb_unplugged(vm, mb_id, sb_id, count);
+ virtio_mem_sbm_set_sb_unplugged(vm, mb_id, sb_id, count);
return rc;
}
/*
+ * Request to unplug a big block.
+ *
+ * Will not modify the state of the big block.
+ */
+static int virtio_mem_bbm_unplug_bb(struct virtio_mem *vm, unsigned long bb_id)
+{
+ const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
+ const uint64_t size = vm->bbm.bb_size;
+
+ return virtio_mem_send_unplug_request(vm, addr, size);
+}
+
+/*
+ * Request to plug a big block.
+ *
+ * Will not modify the state of the big block.
+ */
+static int virtio_mem_bbm_plug_bb(struct virtio_mem *vm, unsigned long bb_id)
+{
+ const uint64_t addr = virtio_mem_bb_id_to_phys(vm, bb_id);
+ const uint64_t size = vm->bbm.bb_size;
+
+ return virtio_mem_send_plug_request(vm, addr, size);
+}
+
+/*
* Unplug the desired number of plugged subblocks of a offline or not-added
* memory block. Will fail if any subblock cannot get unplugged (instead of
* skipping it).
@@ -986,29 +1453,29 @@ static int virtio_mem_mb_unplug_sb(struct virtio_mem *vm, unsigned long mb_id,
*
* Note: can fail after some subblocks were unplugged.
*/
-static int virtio_mem_mb_unplug_any_sb(struct virtio_mem *vm,
- unsigned long mb_id, uint64_t *nb_sb)
+static int virtio_mem_sbm_unplug_any_sb(struct virtio_mem *vm,
+ unsigned long mb_id, uint64_t *nb_sb)
{
int sb_id, count;
int rc;
- sb_id = vm->nb_sb_per_mb - 1;
+ sb_id = vm->sbm.sbs_per_mb - 1;
while (*nb_sb) {
/* Find the next candidate subblock */
while (sb_id >= 0 &&
- virtio_mem_mb_test_sb_unplugged(vm, mb_id, sb_id, 1))
+ virtio_mem_sbm_test_sb_unplugged(vm, mb_id, sb_id, 1))
sb_id--;
if (sb_id < 0)
break;
/* Try to unplug multiple subblocks at a time */
count = 1;
while (count < *nb_sb && sb_id > 0 &&
- virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id - 1, 1)) {
+ virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id - 1, 1)) {
count++;
sb_id--;
}
- rc = virtio_mem_mb_unplug_sb(vm, mb_id, sb_id, count);
+ rc = virtio_mem_sbm_unplug_sb(vm, mb_id, sb_id, count);
if (rc)
return rc;
*nb_sb -= count;
@@ -1025,63 +1492,50 @@ static int virtio_mem_mb_unplug_any_sb(struct virtio_mem *vm,
*
* Note: can fail after some subblocks were unplugged.
*/
-static int virtio_mem_mb_unplug(struct virtio_mem *vm, unsigned long mb_id)
+static int virtio_mem_sbm_unplug_mb(struct virtio_mem *vm, unsigned long mb_id)
{
- uint64_t nb_sb = vm->nb_sb_per_mb;
+ uint64_t nb_sb = vm->sbm.sbs_per_mb;
- return virtio_mem_mb_unplug_any_sb(vm, mb_id, &nb_sb);
+ return virtio_mem_sbm_unplug_any_sb(vm, mb_id, &nb_sb);
}
/*
* Prepare tracking data for the next memory block.
*/
-static int virtio_mem_prepare_next_mb(struct virtio_mem *vm,
- unsigned long *mb_id)
+static int virtio_mem_sbm_prepare_next_mb(struct virtio_mem *vm,
+ unsigned long *mb_id)
{
int rc;
- if (vm->next_mb_id > vm->last_usable_mb_id)
+ if (vm->sbm.next_mb_id > vm->sbm.last_usable_mb_id)
return -ENOSPC;
/* Resize the state array if required. */
- rc = virtio_mem_mb_state_prepare_next_mb(vm);
+ rc = virtio_mem_sbm_mb_states_prepare_next_mb(vm);
if (rc)
return rc;
/* Resize the subblock bitmap if required. */
- rc = virtio_mem_sb_bitmap_prepare_next_mb(vm);
+ rc = virtio_mem_sbm_sb_states_prepare_next_mb(vm);
if (rc)
return rc;
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_UNUSED]++;
- *mb_id = vm->next_mb_id++;
+ vm->sbm.mb_count[VIRTIO_MEM_SBM_MB_UNUSED]++;
+ *mb_id = vm->sbm.next_mb_id++;
return 0;
}
/*
- * Don't add too many blocks that are not onlined yet to avoid running OOM.
- */
-static bool virtio_mem_too_many_mb_offline(struct virtio_mem *vm)
-{
- unsigned long nb_offline;
-
- nb_offline = vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE] +
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL];
- return nb_offline >= VIRTIO_MEM_NB_OFFLINE_THRESHOLD;
-}
-
-/*
* Try to plug the desired number of subblocks and add the memory block
* to Linux.
*
* Will modify the state of the memory block.
*/
-static int virtio_mem_mb_plug_and_add(struct virtio_mem *vm,
- unsigned long mb_id,
- uint64_t *nb_sb)
+static int virtio_mem_sbm_plug_and_add_mb(struct virtio_mem *vm,
+ unsigned long mb_id, uint64_t *nb_sb)
{
- const int count = min_t(int, *nb_sb, vm->nb_sb_per_mb);
- int rc, rc2;
+ const int count = min_t(int, *nb_sb, vm->sbm.sbs_per_mb);
+ int rc;
if (WARN_ON_ONCE(!count))
return -EINVAL;
@@ -1090,7 +1544,7 @@ static int virtio_mem_mb_plug_and_add(struct virtio_mem *vm,
* Plug the requested number of subblocks before adding it to linux,
* so that onlining will directly online all plugged subblocks.
*/
- rc = virtio_mem_mb_plug_sb(vm, mb_id, 0, count);
+ rc = virtio_mem_sbm_plug_sb(vm, mb_id, 0, count);
if (rc)
return rc;
@@ -1098,29 +1552,21 @@ static int virtio_mem_mb_plug_and_add(struct virtio_mem *vm,
* Mark the block properly offline before adding it to Linux,
* so the memory notifiers will find the block in the right state.
*/
- if (count == vm->nb_sb_per_mb)
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE);
+ if (count == vm->sbm.sbs_per_mb)
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE);
else
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL);
/* Add the memory block to linux - if that fails, try to unplug. */
- rc = virtio_mem_mb_add(vm, mb_id);
+ rc = virtio_mem_sbm_add_mb(vm, mb_id);
if (rc) {
- enum virtio_mem_mb_state new_state = VIRTIO_MEM_MB_STATE_UNUSED;
+ int new_state = VIRTIO_MEM_SBM_MB_UNUSED;
- dev_err(&vm->vdev->dev,
- "adding memory block %lu failed with %d\n", mb_id, rc);
- rc2 = virtio_mem_mb_unplug_sb(vm, mb_id, 0, count);
-
- /*
- * TODO: Linux MM does not properly clean up yet in all cases
- * where adding of memory failed - especially on -ENOMEM.
- */
- if (rc2)
- new_state = VIRTIO_MEM_MB_STATE_PLUGGED;
- virtio_mem_mb_set_state(vm, mb_id, new_state);
+ if (virtio_mem_sbm_unplug_sb(vm, mb_id, 0, count))
+ new_state = VIRTIO_MEM_SBM_MB_PLUGGED;
+ virtio_mem_sbm_set_mb_state(vm, mb_id, new_state);
return rc;
}
@@ -1136,8 +1582,9 @@ static int virtio_mem_mb_plug_and_add(struct virtio_mem *vm,
*
* Note: Can fail after some subblocks were successfully plugged.
*/
-static int virtio_mem_mb_plug_any_sb(struct virtio_mem *vm, unsigned long mb_id,
- uint64_t *nb_sb, bool online)
+static int virtio_mem_sbm_plug_any_sb(struct virtio_mem *vm,
+ unsigned long mb_id, uint64_t *nb_sb,
+ bool online)
{
unsigned long pfn, nr_pages;
int sb_id, count;
@@ -1147,17 +1594,16 @@ static int virtio_mem_mb_plug_any_sb(struct virtio_mem *vm, unsigned long mb_id,
return -EINVAL;
while (*nb_sb) {
- sb_id = virtio_mem_mb_first_unplugged_sb(vm, mb_id);
- if (sb_id >= vm->nb_sb_per_mb)
+ sb_id = virtio_mem_sbm_first_unplugged_sb(vm, mb_id);
+ if (sb_id >= vm->sbm.sbs_per_mb)
break;
count = 1;
while (count < *nb_sb &&
- sb_id + count < vm->nb_sb_per_mb &&
- !virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id + count,
- 1))
+ sb_id + count < vm->sbm.sbs_per_mb &&
+ !virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id + count, 1))
count++;
- rc = virtio_mem_mb_plug_sb(vm, mb_id, sb_id, count);
+ rc = virtio_mem_sbm_plug_sb(vm, mb_id, sb_id, count);
if (rc)
return rc;
*nb_sb -= count;
@@ -1166,29 +1612,26 @@ static int virtio_mem_mb_plug_any_sb(struct virtio_mem *vm, unsigned long mb_id,
/* fake-online the pages if the memory block is online */
pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size);
- nr_pages = PFN_DOWN(count * vm->subblock_size);
+ sb_id * vm->sbm.sb_size);
+ nr_pages = PFN_DOWN(count * vm->sbm.sb_size);
virtio_mem_fake_online(pfn, nr_pages);
}
- if (virtio_mem_mb_test_sb_plugged(vm, mb_id, 0, vm->nb_sb_per_mb)) {
+ if (virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) {
if (online)
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE);
else
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE);
}
return 0;
}
-/*
- * Try to plug the requested amount of memory.
- */
-static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
+static int virtio_mem_sbm_plug_request(struct virtio_mem *vm, uint64_t diff)
{
- uint64_t nb_sb = diff / vm->subblock_size;
+ uint64_t nb_sb = diff / vm->sbm.sb_size;
unsigned long mb_id;
int rc;
@@ -1199,18 +1642,18 @@ static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
mutex_lock(&vm->hotplug_mutex);
/* Try to plug subblocks of partially plugged online blocks. */
- virtio_mem_for_each_mb_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL) {
- rc = virtio_mem_mb_plug_any_sb(vm, mb_id, &nb_sb, true);
+ virtio_mem_sbm_for_each_mb(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL) {
+ rc = virtio_mem_sbm_plug_any_sb(vm, mb_id, &nb_sb, true);
if (rc || !nb_sb)
goto out_unlock;
cond_resched();
}
/* Try to plug subblocks of partially plugged offline blocks. */
- virtio_mem_for_each_mb_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL) {
- rc = virtio_mem_mb_plug_any_sb(vm, mb_id, &nb_sb, false);
+ virtio_mem_sbm_for_each_mb(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) {
+ rc = virtio_mem_sbm_plug_any_sb(vm, mb_id, &nb_sb, false);
if (rc || !nb_sb)
goto out_unlock;
cond_resched();
@@ -1223,11 +1666,11 @@ static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
mutex_unlock(&vm->hotplug_mutex);
/* Try to plug and add unused blocks */
- virtio_mem_for_each_mb_state(vm, mb_id, VIRTIO_MEM_MB_STATE_UNUSED) {
- if (virtio_mem_too_many_mb_offline(vm))
+ virtio_mem_sbm_for_each_mb(vm, mb_id, VIRTIO_MEM_SBM_MB_UNUSED) {
+ if (!virtio_mem_could_add_memory(vm, memory_block_size_bytes()))
return -ENOSPC;
- rc = virtio_mem_mb_plug_and_add(vm, mb_id, &nb_sb);
+ rc = virtio_mem_sbm_plug_and_add_mb(vm, mb_id, &nb_sb);
if (rc || !nb_sb)
return rc;
cond_resched();
@@ -1235,13 +1678,13 @@ static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
/* Try to prepare, plug and add new blocks */
while (nb_sb) {
- if (virtio_mem_too_many_mb_offline(vm))
+ if (!virtio_mem_could_add_memory(vm, memory_block_size_bytes()))
return -ENOSPC;
- rc = virtio_mem_prepare_next_mb(vm, &mb_id);
+ rc = virtio_mem_sbm_prepare_next_mb(vm, &mb_id);
if (rc)
return rc;
- rc = virtio_mem_mb_plug_and_add(vm, mb_id, &nb_sb);
+ rc = virtio_mem_sbm_plug_and_add_mb(vm, mb_id, &nb_sb);
if (rc)
return rc;
cond_resched();
@@ -1254,6 +1697,112 @@ out_unlock:
}
/*
+ * Plug a big block and add it to Linux.
+ *
+ * Will modify the state of the big block.
+ */
+static int virtio_mem_bbm_plug_and_add_bb(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ int rc;
+
+ if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) !=
+ VIRTIO_MEM_BBM_BB_UNUSED))
+ return -EINVAL;
+
+ rc = virtio_mem_bbm_plug_bb(vm, bb_id);
+ if (rc)
+ return rc;
+ virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED);
+
+ rc = virtio_mem_bbm_add_bb(vm, bb_id);
+ if (rc) {
+ if (!virtio_mem_bbm_unplug_bb(vm, bb_id))
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_UNUSED);
+ else
+ /* Retry from the main loop. */
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_PLUGGED);
+ return rc;
+ }
+ return 0;
+}
+
+/*
+ * Prepare tracking data for the next big block.
+ */
+static int virtio_mem_bbm_prepare_next_bb(struct virtio_mem *vm,
+ unsigned long *bb_id)
+{
+ int rc;
+
+ if (vm->bbm.next_bb_id > vm->bbm.last_usable_bb_id)
+ return -ENOSPC;
+
+ /* Resize the big block state array if required. */
+ rc = virtio_mem_bbm_bb_states_prepare_next_bb(vm);
+ if (rc)
+ return rc;
+
+ vm->bbm.bb_count[VIRTIO_MEM_BBM_BB_UNUSED]++;
+ *bb_id = vm->bbm.next_bb_id;
+ vm->bbm.next_bb_id++;
+ return 0;
+}
+
+static int virtio_mem_bbm_plug_request(struct virtio_mem *vm, uint64_t diff)
+{
+ uint64_t nb_bb = diff / vm->bbm.bb_size;
+ unsigned long bb_id;
+ int rc;
+
+ if (!nb_bb)
+ return 0;
+
+ /* Try to plug and add unused big blocks */
+ virtio_mem_bbm_for_each_bb(vm, bb_id, VIRTIO_MEM_BBM_BB_UNUSED) {
+ if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size))
+ return -ENOSPC;
+
+ rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id);
+ if (!rc)
+ nb_bb--;
+ if (rc || !nb_bb)
+ return rc;
+ cond_resched();
+ }
+
+ /* Try to prepare, plug and add new big blocks */
+ while (nb_bb) {
+ if (!virtio_mem_could_add_memory(vm, vm->bbm.bb_size))
+ return -ENOSPC;
+
+ rc = virtio_mem_bbm_prepare_next_bb(vm, &bb_id);
+ if (rc)
+ return rc;
+ rc = virtio_mem_bbm_plug_and_add_bb(vm, bb_id);
+ if (!rc)
+ nb_bb--;
+ if (rc)
+ return rc;
+ cond_resched();
+ }
+
+ return 0;
+}
+
+/*
+ * Try to plug the requested amount of memory.
+ */
+static int virtio_mem_plug_request(struct virtio_mem *vm, uint64_t diff)
+{
+ if (vm->in_sbm)
+ return virtio_mem_sbm_plug_request(vm, diff);
+ return virtio_mem_bbm_plug_request(vm, diff);
+}
+
+/*
* Unplug the desired number of plugged subblocks of an offline memory block.
* Will fail if any subblock cannot get unplugged (instead of skipping it).
*
@@ -1262,33 +1811,33 @@ out_unlock:
*
* Note: Can fail after some subblocks were successfully unplugged.
*/
-static int virtio_mem_mb_unplug_any_sb_offline(struct virtio_mem *vm,
- unsigned long mb_id,
- uint64_t *nb_sb)
+static int virtio_mem_sbm_unplug_any_sb_offline(struct virtio_mem *vm,
+ unsigned long mb_id,
+ uint64_t *nb_sb)
{
int rc;
- rc = virtio_mem_mb_unplug_any_sb(vm, mb_id, nb_sb);
+ rc = virtio_mem_sbm_unplug_any_sb(vm, mb_id, nb_sb);
/* some subblocks might have been unplugged even on failure */
- if (!virtio_mem_mb_test_sb_plugged(vm, mb_id, 0, vm->nb_sb_per_mb))
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL);
+ if (!virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb))
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL);
if (rc)
return rc;
- if (virtio_mem_mb_test_sb_unplugged(vm, mb_id, 0, vm->nb_sb_per_mb)) {
+ if (virtio_mem_sbm_test_sb_unplugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) {
/*
* Remove the block from Linux - this should never fail.
* Hinder the block from getting onlined by marking it
* unplugged. Temporarily drop the mutex, so
* any pending GOING_ONLINE requests can be serviced/rejected.
*/
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_UNUSED);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_UNUSED);
mutex_unlock(&vm->hotplug_mutex);
- rc = virtio_mem_mb_remove(vm, mb_id);
+ rc = virtio_mem_sbm_remove_mb(vm, mb_id);
BUG_ON(rc);
mutex_lock(&vm->hotplug_mutex);
}
@@ -1300,38 +1849,31 @@ static int virtio_mem_mb_unplug_any_sb_offline(struct virtio_mem *vm,
*
* Will modify the state of the memory block.
*/
-static int virtio_mem_mb_unplug_sb_online(struct virtio_mem *vm,
- unsigned long mb_id, int sb_id,
- int count)
+static int virtio_mem_sbm_unplug_sb_online(struct virtio_mem *vm,
+ unsigned long mb_id, int sb_id,
+ int count)
{
- const unsigned long nr_pages = PFN_DOWN(vm->subblock_size) * count;
+ const unsigned long nr_pages = PFN_DOWN(vm->sbm.sb_size) * count;
unsigned long start_pfn;
int rc;
start_pfn = PFN_DOWN(virtio_mem_mb_id_to_phys(mb_id) +
- sb_id * vm->subblock_size);
- rc = alloc_contig_range(start_pfn, start_pfn + nr_pages,
- MIGRATE_MOVABLE, GFP_KERNEL);
- if (rc == -ENOMEM)
- /* whoops, out of memory */
- return rc;
- if (rc)
- return -EBUSY;
+ sb_id * vm->sbm.sb_size);
- /* Mark it as fake-offline before unplugging it */
- virtio_mem_set_fake_offline(start_pfn, nr_pages, true);
- adjust_managed_page_count(pfn_to_page(start_pfn), -nr_pages);
+ rc = virtio_mem_fake_offline(start_pfn, nr_pages);
+ if (rc)
+ return rc;
/* Try to unplug the allocated memory */
- rc = virtio_mem_mb_unplug_sb(vm, mb_id, sb_id, count);
+ rc = virtio_mem_sbm_unplug_sb(vm, mb_id, sb_id, count);
if (rc) {
/* Return the memory to the buddy. */
virtio_mem_fake_online(start_pfn, nr_pages);
return rc;
}
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL);
return 0;
}
@@ -1345,34 +1887,34 @@ static int virtio_mem_mb_unplug_sb_online(struct virtio_mem *vm,
* Note: Can fail after some subblocks were successfully unplugged. Can
* return 0 even if subblocks were busy and could not get unplugged.
*/
-static int virtio_mem_mb_unplug_any_sb_online(struct virtio_mem *vm,
- unsigned long mb_id,
- uint64_t *nb_sb)
+static int virtio_mem_sbm_unplug_any_sb_online(struct virtio_mem *vm,
+ unsigned long mb_id,
+ uint64_t *nb_sb)
{
int rc, sb_id;
/* If possible, try to unplug the complete block in one shot. */
- if (*nb_sb >= vm->nb_sb_per_mb &&
- virtio_mem_mb_test_sb_plugged(vm, mb_id, 0, vm->nb_sb_per_mb)) {
- rc = virtio_mem_mb_unplug_sb_online(vm, mb_id, 0,
- vm->nb_sb_per_mb);
+ if (*nb_sb >= vm->sbm.sbs_per_mb &&
+ virtio_mem_sbm_test_sb_plugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) {
+ rc = virtio_mem_sbm_unplug_sb_online(vm, mb_id, 0,
+ vm->sbm.sbs_per_mb);
if (!rc) {
- *nb_sb -= vm->nb_sb_per_mb;
+ *nb_sb -= vm->sbm.sbs_per_mb;
goto unplugged;
} else if (rc != -EBUSY)
return rc;
}
/* Fallback to single subblocks. */
- for (sb_id = vm->nb_sb_per_mb - 1; sb_id >= 0 && *nb_sb; sb_id--) {
+ for (sb_id = vm->sbm.sbs_per_mb - 1; sb_id >= 0 && *nb_sb; sb_id--) {
/* Find the next candidate subblock */
while (sb_id >= 0 &&
- !virtio_mem_mb_test_sb_plugged(vm, mb_id, sb_id, 1))
+ !virtio_mem_sbm_test_sb_plugged(vm, mb_id, sb_id, 1))
sb_id--;
if (sb_id < 0)
break;
- rc = virtio_mem_mb_unplug_sb_online(vm, mb_id, sb_id, 1);
+ rc = virtio_mem_sbm_unplug_sb_online(vm, mb_id, sb_id, 1);
if (rc == -EBUSY)
continue;
else if (rc)
@@ -1386,24 +1928,21 @@ unplugged:
* remove it. This will usually not fail, as no memory is in use
* anymore - however some other notifiers might NACK the request.
*/
- if (virtio_mem_mb_test_sb_unplugged(vm, mb_id, 0, vm->nb_sb_per_mb)) {
+ if (virtio_mem_sbm_test_sb_unplugged(vm, mb_id, 0, vm->sbm.sbs_per_mb)) {
mutex_unlock(&vm->hotplug_mutex);
- rc = virtio_mem_mb_offline_and_remove(vm, mb_id);
+ rc = virtio_mem_sbm_offline_and_remove_mb(vm, mb_id);
mutex_lock(&vm->hotplug_mutex);
if (!rc)
- virtio_mem_mb_set_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_UNUSED);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_UNUSED);
}
return 0;
}
-/*
- * Try to unplug the requested amount of memory.
- */
-static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
+static int virtio_mem_sbm_unplug_request(struct virtio_mem *vm, uint64_t diff)
{
- uint64_t nb_sb = diff / vm->subblock_size;
+ uint64_t nb_sb = diff / vm->sbm.sb_size;
unsigned long mb_id;
int rc;
@@ -1418,20 +1957,17 @@ static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
mutex_lock(&vm->hotplug_mutex);
/* Try to unplug subblocks of partially plugged offline blocks. */
- virtio_mem_for_each_mb_state_rev(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL) {
- rc = virtio_mem_mb_unplug_any_sb_offline(vm, mb_id,
- &nb_sb);
+ virtio_mem_sbm_for_each_mb_rev(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) {
+ rc = virtio_mem_sbm_unplug_any_sb_offline(vm, mb_id, &nb_sb);
if (rc || !nb_sb)
goto out_unlock;
cond_resched();
}
/* Try to unplug subblocks of plugged offline blocks. */
- virtio_mem_for_each_mb_state_rev(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE) {
- rc = virtio_mem_mb_unplug_any_sb_offline(vm, mb_id,
- &nb_sb);
+ virtio_mem_sbm_for_each_mb_rev(vm, mb_id, VIRTIO_MEM_SBM_MB_OFFLINE) {
+ rc = virtio_mem_sbm_unplug_any_sb_offline(vm, mb_id, &nb_sb);
if (rc || !nb_sb)
goto out_unlock;
cond_resched();
@@ -1443,10 +1979,9 @@ static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
}
/* Try to unplug subblocks of partially plugged online blocks. */
- virtio_mem_for_each_mb_state_rev(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL) {
- rc = virtio_mem_mb_unplug_any_sb_online(vm, mb_id,
- &nb_sb);
+ virtio_mem_sbm_for_each_mb_rev(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_ONLINE_PARTIAL) {
+ rc = virtio_mem_sbm_unplug_any_sb_online(vm, mb_id, &nb_sb);
if (rc || !nb_sb)
goto out_unlock;
mutex_unlock(&vm->hotplug_mutex);
@@ -1455,10 +1990,8 @@ static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
}
/* Try to unplug subblocks of plugged online blocks. */
- virtio_mem_for_each_mb_state_rev(vm, mb_id,
- VIRTIO_MEM_MB_STATE_ONLINE) {
- rc = virtio_mem_mb_unplug_any_sb_online(vm, mb_id,
- &nb_sb);
+ virtio_mem_sbm_for_each_mb_rev(vm, mb_id, VIRTIO_MEM_SBM_MB_ONLINE) {
+ rc = virtio_mem_sbm_unplug_any_sb_online(vm, mb_id, &nb_sb);
if (rc || !nb_sb)
goto out_unlock;
mutex_unlock(&vm->hotplug_mutex);
@@ -1474,19 +2007,211 @@ out_unlock:
}
/*
+ * Try to offline and remove a big block from Linux and unplug it. Will fail
+ * with -EBUSY if some memory is busy and cannot get unplugged.
+ *
+ * Will modify the state of the memory block. Might temporarily drop the
+ * hotplug_mutex.
+ */
+static int virtio_mem_bbm_offline_remove_and_unplug_bb(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ const unsigned long start_pfn = PFN_DOWN(virtio_mem_bb_id_to_phys(vm, bb_id));
+ const unsigned long nr_pages = PFN_DOWN(vm->bbm.bb_size);
+ unsigned long end_pfn = start_pfn + nr_pages;
+ unsigned long pfn;
+ struct page *page;
+ int rc;
+
+ if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) !=
+ VIRTIO_MEM_BBM_BB_ADDED))
+ return -EINVAL;
+
+ if (bbm_safe_unplug) {
+ /*
+ * Start by fake-offlining all memory. Once we marked the device
+ * block as fake-offline, all newly onlined memory will
+ * automatically be kept fake-offline. Protect from concurrent
+ * onlining/offlining until we have a consistent state.
+ */
+ mutex_lock(&vm->hotplug_mutex);
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_FAKE_OFFLINE);
+
+ for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+ page = pfn_to_online_page(pfn);
+ if (!page)
+ continue;
+
+ rc = virtio_mem_fake_offline(pfn, PAGES_PER_SECTION);
+ if (rc) {
+ end_pfn = pfn;
+ goto rollback_safe_unplug;
+ }
+ }
+ mutex_unlock(&vm->hotplug_mutex);
+ }
+
+ rc = virtio_mem_bbm_offline_and_remove_bb(vm, bb_id);
+ if (rc) {
+ if (bbm_safe_unplug) {
+ mutex_lock(&vm->hotplug_mutex);
+ goto rollback_safe_unplug;
+ }
+ return rc;
+ }
+
+ rc = virtio_mem_bbm_unplug_bb(vm, bb_id);
+ if (rc)
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_PLUGGED);
+ else
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_UNUSED);
+ return rc;
+
+rollback_safe_unplug:
+ for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
+ page = pfn_to_online_page(pfn);
+ if (!page)
+ continue;
+ virtio_mem_fake_online(pfn, PAGES_PER_SECTION);
+ }
+ virtio_mem_bbm_set_bb_state(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED);
+ mutex_unlock(&vm->hotplug_mutex);
+ return rc;
+}
+
+/*
+ * Try to remove a big block from Linux and unplug it. Will fail with
+ * -EBUSY if some memory is online.
+ *
+ * Will modify the state of the memory block.
+ */
+static int virtio_mem_bbm_remove_and_unplug_bb(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ int rc;
+
+ if (WARN_ON_ONCE(virtio_mem_bbm_get_bb_state(vm, bb_id) !=
+ VIRTIO_MEM_BBM_BB_ADDED))
+ return -EINVAL;
+
+ rc = virtio_mem_bbm_remove_bb(vm, bb_id);
+ if (rc)
+ return -EBUSY;
+
+ rc = virtio_mem_bbm_unplug_bb(vm, bb_id);
+ if (rc)
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_PLUGGED);
+ else
+ virtio_mem_bbm_set_bb_state(vm, bb_id,
+ VIRTIO_MEM_BBM_BB_UNUSED);
+ return rc;
+}
+
+/*
+ * Test if a big block is completely offline.
+ */
+static bool virtio_mem_bbm_bb_is_offline(struct virtio_mem *vm,
+ unsigned long bb_id)
+{
+ const unsigned long start_pfn = PFN_DOWN(virtio_mem_bb_id_to_phys(vm, bb_id));
+ const unsigned long nr_pages = PFN_DOWN(vm->bbm.bb_size);
+ unsigned long pfn;
+
+ for (pfn = start_pfn; pfn < start_pfn + nr_pages;
+ pfn += PAGES_PER_SECTION) {
+ if (pfn_to_online_page(pfn))
+ return false;
+ }
+
+ return true;
+}
+
+static int virtio_mem_bbm_unplug_request(struct virtio_mem *vm, uint64_t diff)
+{
+ uint64_t nb_bb = diff / vm->bbm.bb_size;
+ uint64_t bb_id;
+ int rc;
+
+ if (!nb_bb)
+ return 0;
+
+ /* Try to unplug completely offline big blocks first. */
+ virtio_mem_bbm_for_each_bb_rev(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED) {
+ cond_resched();
+ /*
+ * As we're holding no locks, this check is racy as memory
+ * can get onlined in the meantime - but we'll fail gracefully.
+ */
+ if (!virtio_mem_bbm_bb_is_offline(vm, bb_id))
+ continue;
+ rc = virtio_mem_bbm_remove_and_unplug_bb(vm, bb_id);
+ if (rc == -EBUSY)
+ continue;
+ if (!rc)
+ nb_bb--;
+ if (rc || !nb_bb)
+ return rc;
+ }
+
+ if (!unplug_online)
+ return 0;
+
+ /* Try to unplug any big blocks. */
+ virtio_mem_bbm_for_each_bb_rev(vm, bb_id, VIRTIO_MEM_BBM_BB_ADDED) {
+ cond_resched();
+ rc = virtio_mem_bbm_offline_remove_and_unplug_bb(vm, bb_id);
+ if (rc == -EBUSY)
+ continue;
+ if (!rc)
+ nb_bb--;
+ if (rc || !nb_bb)
+ return rc;
+ }
+
+ return nb_bb ? -EBUSY : 0;
+}
+
+/*
+ * Try to unplug the requested amount of memory.
+ */
+static int virtio_mem_unplug_request(struct virtio_mem *vm, uint64_t diff)
+{
+ if (vm->in_sbm)
+ return virtio_mem_sbm_unplug_request(vm, diff);
+ return virtio_mem_bbm_unplug_request(vm, diff);
+}
+
+/*
* Try to unplug all blocks that couldn't be unplugged before, for example,
* because the hypervisor was busy.
*/
static int virtio_mem_unplug_pending_mb(struct virtio_mem *vm)
{
- unsigned long mb_id;
+ unsigned long id;
int rc;
- virtio_mem_for_each_mb_state(vm, mb_id, VIRTIO_MEM_MB_STATE_PLUGGED) {
- rc = virtio_mem_mb_unplug(vm, mb_id);
+ if (!vm->in_sbm) {
+ virtio_mem_bbm_for_each_bb(vm, id,
+ VIRTIO_MEM_BBM_BB_PLUGGED) {
+ rc = virtio_mem_bbm_unplug_bb(vm, id);
+ if (rc)
+ return rc;
+ virtio_mem_bbm_set_bb_state(vm, id,
+ VIRTIO_MEM_BBM_BB_UNUSED);
+ }
+ return 0;
+ }
+
+ virtio_mem_sbm_for_each_mb(vm, id, VIRTIO_MEM_SBM_MB_PLUGGED) {
+ rc = virtio_mem_sbm_unplug_mb(vm, id);
if (rc)
return rc;
- virtio_mem_mb_set_state(vm, mb_id, VIRTIO_MEM_MB_STATE_UNUSED);
+ virtio_mem_sbm_set_mb_state(vm, id,
+ VIRTIO_MEM_SBM_MB_UNUSED);
}
return 0;
@@ -1511,7 +2236,13 @@ static void virtio_mem_refresh_config(struct virtio_mem *vm)
usable_region_size, &usable_region_size);
end_addr = vm->addr + usable_region_size;
end_addr = min(end_addr, phys_limit);
- vm->last_usable_mb_id = virtio_mem_phys_to_mb_id(end_addr) - 1;
+
+ if (vm->in_sbm)
+ vm->sbm.last_usable_mb_id =
+ virtio_mem_phys_to_mb_id(end_addr) - 1;
+ else
+ vm->bbm.last_usable_bb_id =
+ virtio_mem_phys_to_bb_id(vm, end_addr) - 1;
/* see if there is a request to change the size */
virtio_cread_le(vm->vdev, struct virtio_mem_config, requested_size,
@@ -1535,6 +2266,7 @@ static void virtio_mem_run_wq(struct work_struct *work)
if (vm->broken)
return;
+ atomic_set(&vm->wq_active, 1);
retry:
rc = 0;
@@ -1595,6 +2327,8 @@ retry:
"unknown error, marking device broken: %d\n", rc);
vm->broken = true;
}
+
+ atomic_set(&vm->wq_active, 0);
}
static enum hrtimer_restart virtio_mem_timer_expired(struct hrtimer *timer)
@@ -1631,6 +2365,7 @@ static int virtio_mem_init_vq(struct virtio_mem *vm)
static int virtio_mem_init(struct virtio_mem *vm)
{
const uint64_t phys_limit = 1UL << MAX_PHYSMEM_BITS;
+ uint64_t sb_size, addr;
uint16_t node_id;
if (!vm->vdev->config->get) {
@@ -1659,15 +2394,9 @@ static int virtio_mem_init(struct virtio_mem *vm)
virtio_cread_le(vm->vdev, struct virtio_mem_config, region_size,
&vm->region_size);
- /*
- * We always hotplug memory in memory block granularity. This way,
- * we have to wait for exactly one memory block to online.
- */
- if (vm->device_block_size > memory_block_size_bytes()) {
- dev_err(&vm->vdev->dev,
- "The block size is not supported (too big).\n");
- return -EINVAL;
- }
+ /* Determine the nid for the device based on the lowest address. */
+ if (vm->nid == NUMA_NO_NODE)
+ vm->nid = memory_add_physaddr_to_nid(vm->addr);
/* bad device setup - warn only */
if (!IS_ALIGNED(vm->addr, memory_block_size_bytes()))
@@ -1681,23 +2410,57 @@ static int virtio_mem_init(struct virtio_mem *vm)
"Some memory is not addressable. This can make some memory unusable.\n");
/*
- * Calculate the subblock size:
- * - At least MAX_ORDER - 1 / pageblock_order.
- * - At least the device block size.
- * In the worst case, a single subblock per memory block.
+ * We want subblocks to span at least MAX_ORDER_NR_PAGES and
+ * pageblock_nr_pages pages. This:
+ * - Simplifies our page onlining code (virtio_mem_online_page_cb)
+ * and fake page onlining code (virtio_mem_fake_online).
+ * - Is required for now for alloc_contig_range() to work reliably -
+ * it doesn't properly handle smaller granularity on ZONE_NORMAL.
*/
- vm->subblock_size = PAGE_SIZE * 1ul << max_t(uint32_t, MAX_ORDER - 1,
- pageblock_order);
- vm->subblock_size = max_t(uint64_t, vm->device_block_size,
- vm->subblock_size);
- vm->nb_sb_per_mb = memory_block_size_bytes() / vm->subblock_size;
-
- /* Round up to the next full memory block */
- vm->first_mb_id = virtio_mem_phys_to_mb_id(vm->addr - 1 +
- memory_block_size_bytes());
- vm->next_mb_id = vm->first_mb_id;
- vm->last_mb_id = virtio_mem_phys_to_mb_id(vm->addr +
- vm->region_size) - 1;
+ sb_size = max_t(uint64_t, MAX_ORDER_NR_PAGES,
+ pageblock_nr_pages) * PAGE_SIZE;
+ sb_size = max_t(uint64_t, vm->device_block_size, sb_size);
+
+ if (sb_size < memory_block_size_bytes() && !force_bbm) {
+ /* SBM: At least two subblocks per Linux memory block. */
+ vm->in_sbm = true;
+ vm->sbm.sb_size = sb_size;
+ vm->sbm.sbs_per_mb = memory_block_size_bytes() /
+ vm->sbm.sb_size;
+
+ /* Round up to the next full memory block */
+ addr = vm->addr + memory_block_size_bytes() - 1;
+ vm->sbm.first_mb_id = virtio_mem_phys_to_mb_id(addr);
+ vm->sbm.next_mb_id = vm->sbm.first_mb_id;
+ } else {
+ /* BBM: At least one Linux memory block. */
+ vm->bbm.bb_size = max_t(uint64_t, vm->device_block_size,
+ memory_block_size_bytes());
+
+ if (bbm_block_size) {
+ if (!is_power_of_2(bbm_block_size)) {
+ dev_warn(&vm->vdev->dev,
+ "bbm_block_size is not a power of 2");
+ } else if (bbm_block_size < vm->bbm.bb_size) {
+ dev_warn(&vm->vdev->dev,
+ "bbm_block_size is too small");
+ } else {
+ vm->bbm.bb_size = bbm_block_size;
+ }
+ }
+
+ /* Round up to the next aligned big block */
+ addr = vm->addr + vm->bbm.bb_size - 1;
+ vm->bbm.first_bb_id = virtio_mem_phys_to_bb_id(vm, addr);
+ vm->bbm.next_bb_id = vm->bbm.first_bb_id;
+ }
+
+ /* Prepare the offline threshold - make sure we can add two blocks. */
+ vm->offline_threshold = max_t(uint64_t, 2 * memory_block_size_bytes(),
+ VIRTIO_MEM_DEFAULT_OFFLINE_THRESHOLD);
+ /* In BBM, we also want at least two big blocks. */
+ vm->offline_threshold = max_t(uint64_t, 2 * vm->bbm.bb_size,
+ vm->offline_threshold);
dev_info(&vm->vdev->dev, "start address: 0x%llx", vm->addr);
dev_info(&vm->vdev->dev, "region size: 0x%llx", vm->region_size);
@@ -1705,9 +2468,13 @@ static int virtio_mem_init(struct virtio_mem *vm)
(unsigned long long)vm->device_block_size);
dev_info(&vm->vdev->dev, "memory block size: 0x%lx",
memory_block_size_bytes());
- dev_info(&vm->vdev->dev, "subblock size: 0x%llx",
- (unsigned long long)vm->subblock_size);
- if (vm->nid != NUMA_NO_NODE)
+ if (vm->in_sbm)
+ dev_info(&vm->vdev->dev, "subblock size: 0x%llx",
+ (unsigned long long)vm->sbm.sb_size);
+ else
+ dev_info(&vm->vdev->dev, "big block size: 0x%llx",
+ (unsigned long long)vm->bbm.bb_size);
+ if (vm->nid != NUMA_NO_NODE && IS_ENABLED(CONFIG_NUMA))
dev_info(&vm->vdev->dev, "nid: %d", vm->nid);
return 0;
@@ -1753,6 +2520,20 @@ static void virtio_mem_delete_resource(struct virtio_mem *vm)
vm->parent_resource = NULL;
}
+static int virtio_mem_range_has_system_ram(struct resource *res, void *arg)
+{
+ return 1;
+}
+
+static bool virtio_mem_has_memory_added(struct virtio_mem *vm)
+{
+ const unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
+
+ return walk_iomem_res_desc(IORES_DESC_NONE, flags, vm->addr,
+ vm->addr + vm->region_size, NULL,
+ virtio_mem_range_has_system_ram) == 1;
+}
+
static int virtio_mem_probe(struct virtio_device *vdev)
{
struct virtio_mem *vm;
@@ -1849,21 +2630,24 @@ static void virtio_mem_remove(struct virtio_device *vdev)
cancel_work_sync(&vm->wq);
hrtimer_cancel(&vm->retry_timer);
- /*
- * After we unregistered our callbacks, user space can online partially
- * plugged offline blocks. Make sure to remove them.
- */
- virtio_mem_for_each_mb_state(vm, mb_id,
- VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL) {
- rc = virtio_mem_mb_remove(vm, mb_id);
- BUG_ON(rc);
- virtio_mem_mb_set_state(vm, mb_id, VIRTIO_MEM_MB_STATE_UNUSED);
+ if (vm->in_sbm) {
+ /*
+ * After we unregistered our callbacks, user space can online
+ * partially plugged offline blocks. Make sure to remove them.
+ */
+ virtio_mem_sbm_for_each_mb(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_OFFLINE_PARTIAL) {
+ rc = virtio_mem_sbm_remove_mb(vm, mb_id);
+ BUG_ON(rc);
+ virtio_mem_sbm_set_mb_state(vm, mb_id,
+ VIRTIO_MEM_SBM_MB_UNUSED);
+ }
+ /*
+ * After we unregistered our callbacks, user space can no longer
+ * offline partially plugged online memory blocks. No need to
+ * worry about them.
+ */
}
- /*
- * After we unregistered our callbacks, user space can no longer
- * offline partially plugged online memory blocks. No need to worry
- * about them.
- */
/* unregister callbacks */
unregister_virtio_mem_device(vm);
@@ -1874,10 +2658,7 @@ static void virtio_mem_remove(struct virtio_device *vdev)
* the system. And there is no way to stop the driver/device from going
* away. Warn at least.
*/
- if (vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE] ||
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_OFFLINE_PARTIAL] ||
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_ONLINE] ||
- vm->nb_mb_state[VIRTIO_MEM_MB_STATE_ONLINE_PARTIAL]) {
+ if (virtio_mem_has_memory_added(vm)) {
dev_warn(&vdev->dev, "device still has system memory added\n");
} else {
virtio_mem_delete_resource(vm);
@@ -1885,8 +2666,12 @@ static void virtio_mem_remove(struct virtio_device *vdev)
}
/* remove all tracking data - no locking needed */
- vfree(vm->mb_state);
- vfree(vm->sb_bitmap);
+ if (vm->in_sbm) {
+ vfree(vm->sbm.mb_states);
+ vfree(vm->sbm.sb_states);
+ } else {
+ vfree(vm->bbm.bb_states);
+ }
/* reset the device and cleanup the queues */
vdev->config->reset(vdev);
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index becc77697960..71e16b53e9c1 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1608,7 +1608,6 @@ static struct virtqueue *vring_create_virtqueue_packed(
vq->num_added = 0;
vq->packed_ring = true;
vq->use_dma_api = vring_use_dma_api(vdev);
- list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
vq->in_use = false;
vq->last_add_time_valid = false;
@@ -1669,6 +1668,7 @@ static struct virtqueue *vring_create_virtqueue_packed(
cpu_to_le16(vq->packed.event_flags_shadow);
}
+ list_add_tail(&vq->vq.list, &vdev->vqs);
return &vq->vq;
err_desc_extra:
@@ -1676,9 +1676,9 @@ err_desc_extra:
err_desc_state:
kfree(vq);
err_vq:
- vring_free_queue(vdev, event_size_in_bytes, device, ring_dma_addr);
+ vring_free_queue(vdev, event_size_in_bytes, device, device_event_dma_addr);
err_device:
- vring_free_queue(vdev, event_size_in_bytes, driver, ring_dma_addr);
+ vring_free_queue(vdev, event_size_in_bytes, driver, driver_event_dma_addr);
err_driver:
vring_free_queue(vdev, ring_size_in_bytes, ring, ring_dma_addr);
err_ring:
@@ -2085,7 +2085,6 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
vq->last_used_idx = 0;
vq->num_added = 0;
vq->use_dma_api = vring_use_dma_api(vdev);
- list_add_tail(&vq->vq.list, &vdev->vqs);
#ifdef DEBUG
vq->in_use = false;
vq->last_add_time_valid = false;
@@ -2127,6 +2126,7 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index,
memset(vq->split.desc_state, 0, vring.num *
sizeof(struct vring_desc_state_split));
+ list_add_tail(&vq->vq.list, &vdev->vqs);
return &vq->vq;
}
EXPORT_SYMBOL_GPL(__vring_new_virtqueue);