[PATCH v3 01/20] vmw_balloon: handle commands in a single function.
From: Nadav Amit
Date: Wed Sep 26 2018 - 15:16:40 EST
By inlining the hypercall interface, we can unify several operations
into one central point in the code:
- Updating the target.
- Updating when a reset is needed.
- Update statistics (which will be done later in the patch-set).
- Print debug-messages (although they cannot be enabled as selectively).
Reviewed-by: Xavier Deguillard <xdeguillard@xxxxxxxxxx>
Signed-off-by: Nadav Amit <namit@xxxxxxxxxx>
---
drivers/misc/vmw_balloon.c | 223 +++++++++++++++++++------------------
1 file changed, 116 insertions(+), 107 deletions(-)
diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c
index 2543ef1ece17..0a4d5501f805 100644
--- a/drivers/misc/vmw_balloon.c
+++ b/drivers/misc/vmw_balloon.c
@@ -138,6 +138,15 @@ enum vmwballoon_capabilities {
#define VMW_BALLOON_BATCH_STATUS_MASK ((1UL << 5) - 1)
#define VMW_BALLOON_BATCH_PAGE_MASK (~((1UL << PAGE_SHIFT) - 1))
+#define VMW_BALLOON_CMD_WITH_TARGET_MASK \
+ ((1UL << VMW_BALLOON_CMD_GET_TARGET) | \
+ (1UL << VMW_BALLOON_CMD_LOCK) | \
+ (1UL << VMW_BALLOON_CMD_UNLOCK) | \
+ (1UL << VMW_BALLOON_CMD_BATCHED_LOCK) | \
+ (1UL << VMW_BALLOON_CMD_BATCHED_UNLOCK) | \
+ (1UL << VMW_BALLOON_CMD_BATCHED_2M_LOCK) | \
+ (1UL << VMW_BALLOON_CMD_BATCHED_2M_UNLOCK))
+
struct vmballoon_batch_page {
u64 pages[VMW_BALLOON_BATCH_MAX_PAGES];
};
@@ -159,28 +168,6 @@ static void vmballoon_batch_set_pa(struct vmballoon_batch_page *batch, int idx,
batch->pages[idx] = pa;
}
-
-#define VMWARE_BALLOON_CMD(cmd, arg1, arg2, result) \
-({ \
- unsigned long __status, __dummy1, __dummy2, __dummy3; \
- __asm__ __volatile__ ("inl %%dx" : \
- "=a"(__status), \
- "=c"(__dummy1), \
- "=d"(__dummy2), \
- "=b"(result), \
- "=S" (__dummy3) : \
- "0"(VMW_BALLOON_HV_MAGIC), \
- "1"(VMW_BALLOON_CMD_##cmd), \
- "2"(VMW_BALLOON_HV_PORT), \
- "3"(arg1), \
- "4" (arg2) : \
- "memory"); \
- if (VMW_BALLOON_CMD_##cmd == VMW_BALLOON_CMD_START) \
- result = __dummy1; \
- result &= -1UL; \
- __status & -1UL; \
-})
-
#ifdef CONFIG_DEBUG_FS
struct vmballoon_stats {
unsigned int timer;
@@ -220,9 +207,9 @@ struct vmballoon;
struct vmballoon_ops {
void (*add_page)(struct vmballoon *b, int idx, struct page *p);
int (*lock)(struct vmballoon *b, unsigned int num_pages,
- bool is_2m_pages, unsigned int *target);
+ bool is_2m_pages);
int (*unlock)(struct vmballoon *b, unsigned int num_pages,
- bool is_2m_pages, unsigned int *target);
+ bool is_2m_pages);
};
struct vmballoon_page_size {
@@ -272,18 +259,64 @@ struct vmballoon {
static struct vmballoon balloon;
+static inline unsigned long
+__vmballoon_cmd(struct vmballoon *b, unsigned long cmd, unsigned long arg1,
+ unsigned long arg2, unsigned long *result)
+{
+ unsigned long status, dummy1, dummy2, dummy3, local_result;
+
+ asm volatile ("inl %%dx" :
+ "=a"(status),
+ "=c"(dummy1),
+ "=d"(dummy2),
+ "=b"(local_result),
+ "=S"(dummy3) :
+ "0"(VMW_BALLOON_HV_MAGIC),
+ "1"(cmd),
+ "2"(VMW_BALLOON_HV_PORT),
+ "3"(arg1),
+ "4"(arg2) :
+ "memory");
+
+ /* update the result if needed */
+ if (result)
+ *result = (cmd == VMW_BALLOON_CMD_START) ? dummy1 :
+ local_result;
+
+ /* update target when applicable */
+ if (status == VMW_BALLOON_SUCCESS &&
+ ((1ul << cmd) & VMW_BALLOON_CMD_WITH_TARGET_MASK))
+ b->target = local_result;
+
+ /* mark reset required accordingly */
+ if (status == VMW_BALLOON_ERROR_RESET)
+ b->reset_required = true;
+
+ return status;
+}
+
+static __always_inline unsigned long
+vmballoon_cmd(struct vmballoon *b, unsigned long cmd, unsigned long arg1,
+ unsigned long arg2)
+{
+ unsigned long dummy;
+
+ return __vmballoon_cmd(b, cmd, arg1, arg2, &dummy);
+}
+
/*
* Send "start" command to the host, communicating supported version
* of the protocol.
*/
static bool vmballoon_send_start(struct vmballoon *b, unsigned long req_caps)
{
- unsigned long status, capabilities, dummy = 0;
+ unsigned long status, capabilities;
bool success;
STATS_INC(b->stats.start);
- status = VMWARE_BALLOON_CMD(START, req_caps, dummy, capabilities);
+ status = __vmballoon_cmd(b, VMW_BALLOON_CMD_START, req_caps, 0,
+ &capabilities);
switch (status) {
case VMW_BALLOON_SUCCESS_WITH_CAPABILITIES:
@@ -316,21 +349,6 @@ static bool vmballoon_send_start(struct vmballoon *b, unsigned long req_caps)
return success;
}
-static bool vmballoon_check_status(struct vmballoon *b, unsigned long status)
-{
- switch (status) {
- case VMW_BALLOON_SUCCESS:
- return true;
-
- case VMW_BALLOON_ERROR_RESET:
- b->reset_required = true;
- /* fall through */
-
- default:
- return false;
- }
-}
-
/*
* Communicate guest type to the host so that it can adjust ballooning
* algorithm to the one most appropriate for the guest. This command
@@ -339,14 +357,14 @@ static bool vmballoon_check_status(struct vmballoon *b, unsigned long status)
*/
static bool vmballoon_send_guest_id(struct vmballoon *b)
{
- unsigned long status, dummy = 0;
+ unsigned long status;
- status = VMWARE_BALLOON_CMD(GUEST_ID, VMW_BALLOON_GUEST_ID, dummy,
- dummy);
+ status = vmballoon_cmd(b, VMW_BALLOON_CMD_GUEST_ID,
+ VMW_BALLOON_GUEST_ID, 0);
STATS_INC(b->stats.guest_type);
- if (vmballoon_check_status(b, status))
+ if (status == VMW_BALLOON_SUCCESS)
return true;
pr_debug("%s - failed, hv returns %ld\n", __func__, status);
@@ -365,12 +383,10 @@ static u16 vmballoon_page_size(bool is_2m_page)
/*
* Retrieve desired balloon size from the host.
*/
-static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
+static bool vmballoon_send_get_target(struct vmballoon *b)
{
unsigned long status;
- unsigned long target;
unsigned long limit;
- unsigned long dummy = 0;
u32 limit32;
/*
@@ -389,11 +405,10 @@ static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
/* update stats */
STATS_INC(b->stats.target);
- status = VMWARE_BALLOON_CMD(GET_TARGET, limit, dummy, target);
- if (vmballoon_check_status(b, status)) {
- *new_target = target;
+ status = vmballoon_cmd(b, VMW_BALLOON_CMD_GET_TARGET, limit, 0);
+
+ if (status == VMW_BALLOON_SUCCESS)
return true;
- }
pr_debug("%s - failed, hv returns %ld\n", __func__, status);
STATS_INC(b->stats.target_fail);
@@ -406,9 +421,9 @@ static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target)
* check the return value and maybe submit a different page.
*/
static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
- unsigned int *hv_status, unsigned int *target)
+ unsigned int *hv_status)
{
- unsigned long status, dummy = 0;
+ unsigned long status;
u32 pfn32;
pfn32 = (u32)pfn;
@@ -417,8 +432,9 @@ static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
STATS_INC(b->stats.lock[false]);
- *hv_status = status = VMWARE_BALLOON_CMD(LOCK, pfn, dummy, *target);
- if (vmballoon_check_status(b, status))
+ *hv_status = status = vmballoon_cmd(b, VMW_BALLOON_CMD_LOCK, pfn, 0);
+
+ if (status == VMW_BALLOON_SUCCESS)
return 0;
pr_debug("%s - ppn %lx, hv returns %ld\n", __func__, pfn, status);
@@ -427,21 +443,19 @@ static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn,
}
static int vmballoon_send_batched_lock(struct vmballoon *b,
- unsigned int num_pages, bool is_2m_pages, unsigned int *target)
+ unsigned int num_pages, bool is_2m_pages)
{
- unsigned long status;
unsigned long pfn = PHYS_PFN(virt_to_phys(b->batch_page));
+ unsigned long status, cmd;
STATS_INC(b->stats.lock[is_2m_pages]);
- if (is_2m_pages)
- status = VMWARE_BALLOON_CMD(BATCHED_2M_LOCK, pfn, num_pages,
- *target);
- else
- status = VMWARE_BALLOON_CMD(BATCHED_LOCK, pfn, num_pages,
- *target);
+ cmd = is_2m_pages ? VMW_BALLOON_CMD_BATCHED_2M_LOCK :
+ VMW_BALLOON_CMD_BATCHED_LOCK;
- if (vmballoon_check_status(b, status))
+ status = vmballoon_cmd(b, cmd, pfn, num_pages);
+
+ if (status == VMW_BALLOON_SUCCESS)
return 0;
pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status);
@@ -453,10 +467,9 @@ static int vmballoon_send_batched_lock(struct vmballoon *b,
* Notify the host that guest intends to release given page back into
* the pool of available (to the guest) pages.
*/
-static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn,
- unsigned int *target)
+static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn)
{
- unsigned long status, dummy = 0;
+ unsigned long status;
u32 pfn32;
pfn32 = (u32)pfn;
@@ -465,8 +478,8 @@ static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn,
STATS_INC(b->stats.unlock[false]);
- status = VMWARE_BALLOON_CMD(UNLOCK, pfn, dummy, *target);
- if (vmballoon_check_status(b, status))
+ status = vmballoon_cmd(b, VMW_BALLOON_CMD_UNLOCK, pfn, 0);
+ if (status == VMW_BALLOON_SUCCESS)
return true;
pr_debug("%s - ppn %lx, hv returns %ld\n", __func__, pfn, status);
@@ -475,21 +488,19 @@ static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn,
}
static bool vmballoon_send_batched_unlock(struct vmballoon *b,
- unsigned int num_pages, bool is_2m_pages, unsigned int *target)
+ unsigned int num_pages, bool is_2m_pages)
{
- unsigned long status;
unsigned long pfn = PHYS_PFN(virt_to_phys(b->batch_page));
+ unsigned long status, cmd;
STATS_INC(b->stats.unlock[is_2m_pages]);
- if (is_2m_pages)
- status = VMWARE_BALLOON_CMD(BATCHED_2M_UNLOCK, pfn, num_pages,
- *target);
- else
- status = VMWARE_BALLOON_CMD(BATCHED_UNLOCK, pfn, num_pages,
- *target);
+ cmd = is_2m_pages ? VMW_BALLOON_CMD_BATCHED_2M_UNLOCK :
+ VMW_BALLOON_CMD_BATCHED_UNLOCK;
+
+ status = vmballoon_cmd(b, cmd, pfn, num_pages);
- if (vmballoon_check_status(b, status))
+ if (status == VMW_BALLOON_SUCCESS)
return true;
pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status);
@@ -550,7 +561,7 @@ static void vmballoon_pop(struct vmballoon *b)
* inflation cycle.
*/
static int vmballoon_lock_page(struct vmballoon *b, unsigned int num_pages,
- bool is_2m_pages, unsigned int *target)
+ bool is_2m_pages)
{
int locked, hv_status;
struct page *page = b->page;
@@ -558,8 +569,8 @@ static int vmballoon_lock_page(struct vmballoon *b, unsigned int num_pages,
/* is_2m_pages can never happen as 2m pages support implies batching */
- locked = vmballoon_send_lock_page(b, page_to_pfn(page), &hv_status,
- target);
+ locked = vmballoon_send_lock_page(b, page_to_pfn(page), &hv_status);
+
if (locked) {
STATS_INC(b->stats.refused_alloc[false]);
@@ -594,13 +605,13 @@ static int vmballoon_lock_page(struct vmballoon *b, unsigned int num_pages,
}
static int vmballoon_lock_batched_page(struct vmballoon *b,
- unsigned int num_pages, bool is_2m_pages, unsigned int *target)
+ unsigned int num_pages, bool is_2m_pages)
{
int locked, i;
u16 size_per_page = vmballoon_page_size(is_2m_pages);
- locked = vmballoon_send_batched_lock(b, num_pages, is_2m_pages,
- target);
+ locked = vmballoon_send_batched_lock(b, num_pages, is_2m_pages);
+
if (locked > 0) {
for (i = 0; i < num_pages; i++) {
u64 pa = vmballoon_batch_get_pa(b->batch_page, i);
@@ -653,14 +664,14 @@ static int vmballoon_lock_batched_page(struct vmballoon *b,
* to use, if needed.
*/
static int vmballoon_unlock_page(struct vmballoon *b, unsigned int num_pages,
- bool is_2m_pages, unsigned int *target)
+ bool is_2m_pages)
{
struct page *page = b->page;
struct vmballoon_page_size *page_size = &b->page_sizes[false];
/* is_2m_pages can never happen as 2m pages support implies batching */
- if (!vmballoon_send_unlock_page(b, page_to_pfn(page), target)) {
+ if (!vmballoon_send_unlock_page(b, page_to_pfn(page))) {
list_add(&page->lru, &page_size->pages);
return -EIO;
}
@@ -676,15 +687,14 @@ static int vmballoon_unlock_page(struct vmballoon *b, unsigned int num_pages,
}
static int vmballoon_unlock_batched_page(struct vmballoon *b,
- unsigned int num_pages, bool is_2m_pages,
- unsigned int *target)
+ unsigned int num_pages, bool is_2m_pages)
{
int locked, i, ret = 0;
bool hv_success;
u16 size_per_page = vmballoon_page_size(is_2m_pages);
- hv_success = vmballoon_send_batched_unlock(b, num_pages, is_2m_pages,
- target);
+ hv_success = vmballoon_send_batched_unlock(b, num_pages, is_2m_pages);
+
if (!hv_success)
ret = -EIO;
@@ -799,7 +809,7 @@ static void vmballoon_inflate(struct vmballoon *b)
STATS_INC(b->stats.alloc_fail[is_2m_pages]);
if (is_2m_pages) {
- b->ops->lock(b, num_pages, true, &b->target);
+ b->ops->lock(b, num_pages, true);
/*
* ignore errors from locking as we now switch
@@ -838,8 +848,8 @@ static void vmballoon_inflate(struct vmballoon *b)
b->ops->add_page(b, num_pages++, page);
if (num_pages == b->batch_max_pages) {
- error = b->ops->lock(b, num_pages, is_2m_pages,
- &b->target);
+ error = b->ops->lock(b, num_pages, is_2m_pages);
+
num_pages = 0;
if (error)
break;
@@ -849,7 +859,7 @@ static void vmballoon_inflate(struct vmballoon *b)
}
if (num_pages > 0)
- b->ops->lock(b, num_pages, is_2m_pages, &b->target);
+ b->ops->lock(b, num_pages, is_2m_pages);
vmballoon_release_refused_pages(b, true);
vmballoon_release_refused_pages(b, false);
@@ -887,7 +897,7 @@ static void vmballoon_deflate(struct vmballoon *b)
int error;
error = b->ops->unlock(b, num_pages,
- is_2m_pages, &b->target);
+ is_2m_pages);
num_pages = 0;
if (error)
return;
@@ -897,7 +907,7 @@ static void vmballoon_deflate(struct vmballoon *b)
}
if (num_pages > 0)
- b->ops->unlock(b, num_pages, is_2m_pages, &b->target);
+ b->ops->unlock(b, num_pages, is_2m_pages);
}
}
@@ -942,10 +952,9 @@ static void vmballoon_doorbell(void *client_data)
*/
static void vmballoon_vmci_cleanup(struct vmballoon *b)
{
- int error;
+ vmballoon_cmd(b, VMW_BALLOON_CMD_VMCI_DOORBELL_SET,
+ VMCI_INVALID_ID, VMCI_INVALID_ID);
- VMWARE_BALLOON_CMD(VMCI_DOORBELL_SET, VMCI_INVALID_ID,
- VMCI_INVALID_ID, error);
STATS_INC(b->stats.doorbell_unset);
if (!vmci_handle_is_invalid(b->vmci_doorbell)) {
@@ -959,7 +968,7 @@ static void vmballoon_vmci_cleanup(struct vmballoon *b)
*/
static int vmballoon_vmci_init(struct vmballoon *b)
{
- unsigned long error, dummy;
+ unsigned long error;
if ((b->capabilities & VMW_BALLOON_SIGNALLED_WAKEUP_CMD) == 0)
return 0;
@@ -971,8 +980,9 @@ static int vmballoon_vmci_init(struct vmballoon *b)
if (error != VMCI_SUCCESS)
goto fail;
- error = VMWARE_BALLOON_CMD(VMCI_DOORBELL_SET, b->vmci_doorbell.context,
- b->vmci_doorbell.resource, dummy);
+ error = __vmballoon_cmd(b, VMW_BALLOON_CMD_VMCI_DOORBELL_SET,
+ b->vmci_doorbell.context,
+ b->vmci_doorbell.resource, NULL);
STATS_INC(b->stats.doorbell_set);
@@ -1038,17 +1048,16 @@ static void vmballoon_work(struct work_struct *work)
{
struct delayed_work *dwork = to_delayed_work(work);
struct vmballoon *b = container_of(dwork, struct vmballoon, dwork);
- unsigned int target;
STATS_INC(b->stats.timer);
if (b->reset_required)
vmballoon_reset(b);
- if (!b->reset_required && vmballoon_send_get_target(b, &target)) {
- /* update target, adjust size */
- b->target = target;
+ if (!b->reset_required && vmballoon_send_get_target(b)) {
+ unsigned long target = b->target;
+ /* update target, adjust size */
if (b->size < target)
vmballoon_inflate(b);
else if (target == 0 ||
--
2.17.1