diff options
Diffstat (limited to 'drivers/misc/vmw_balloon.c')
| -rw-r--r-- | drivers/misc/vmw_balloon.c | 1802 |
1 files changed, 1073 insertions, 729 deletions
diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c index 2543ef1ece17..9b0b3fa4f836 100644 --- a/drivers/misc/vmw_balloon.c +++ b/drivers/misc/vmw_balloon.c @@ -25,6 +25,9 @@ #include <linux/workqueue.h> #include <linux/debugfs.h> #include <linux/seq_file.h> +#include <linux/rwsem.h> +#include <linux/slab.h> +#include <linux/spinlock.h> #include <linux/vmw_vmci_defs.h> #include <linux/vmw_vmci_api.h> #include <asm/hypervisor.h> @@ -37,20 +40,20 @@ MODULE_ALIAS("vmware_vmmemctl"); MODULE_LICENSE("GPL"); /* - * Use __GFP_HIGHMEM to allow pages from HIGHMEM zone. We don't - * allow wait (__GFP_RECLAIM) for NOSLEEP page allocations. Use - * __GFP_NOWARN, to suppress page allocation failure warnings. + * Use __GFP_HIGHMEM to allow pages from HIGHMEM zone. We don't allow wait + * (__GFP_RECLAIM) for huge page allocations. Use __GFP_NOWARN, to suppress page + * allocation failure warnings. Disallow access to emergency low-memory pools. */ -#define VMW_PAGE_ALLOC_NOSLEEP (__GFP_HIGHMEM|__GFP_NOWARN) +#define VMW_HUGE_PAGE_ALLOC_FLAGS (__GFP_HIGHMEM|__GFP_NOWARN| \ + __GFP_NOMEMALLOC) /* - * Use GFP_HIGHUSER when executing in a separate kernel thread - * context and allocation can sleep. This is less stressful to - * the guest memory system, since it allows the thread to block - * while memory is reclaimed, and won't take pages from emergency - * low-memory pools. + * Use __GFP_HIGHMEM to allow pages from HIGHMEM zone. We allow lightweight + * reclamation (__GFP_NORETRY). Use __GFP_NOWARN, to suppress page allocation + * failure warnings. Disallow access to emergency low-memory pools. */ -#define VMW_PAGE_ALLOC_CANSLEEP (GFP_HIGHUSER) +#define VMW_PAGE_ALLOC_FLAGS (__GFP_HIGHMEM|__GFP_NOWARN| \ + __GFP_NOMEMALLOC|__GFP_NORETRY) /* Maximum number of refused pages we accumulate during inflation cycle */ #define VMW_BALLOON_MAX_REFUSED 16 @@ -77,225 +80,420 @@ enum vmwballoon_capabilities { | VMW_BALLOON_BATCHED_2M_CMDS \ | VMW_BALLOON_SIGNALLED_WAKEUP_CMD) -#define VMW_BALLOON_2M_SHIFT (9) -#define VMW_BALLOON_NUM_PAGE_SIZES (2) +#define VMW_BALLOON_2M_ORDER (PMD_SHIFT - PAGE_SHIFT) -/* - * Backdoor commands availability: - * - * START, GET_TARGET and GUEST_ID are always available, - * - * VMW_BALLOON_BASIC_CMDS: - * LOCK and UNLOCK commands, - * VMW_BALLOON_BATCHED_CMDS: - * BATCHED_LOCK and BATCHED_UNLOCK commands. - * VMW BALLOON_BATCHED_2M_CMDS: - * BATCHED_2M_LOCK and BATCHED_2M_UNLOCK commands, - * VMW VMW_BALLOON_SIGNALLED_WAKEUP_CMD: - * VMW_BALLOON_CMD_VMCI_DOORBELL_SET command. - */ -#define VMW_BALLOON_CMD_START 0 -#define VMW_BALLOON_CMD_GET_TARGET 1 -#define VMW_BALLOON_CMD_LOCK 2 -#define VMW_BALLOON_CMD_UNLOCK 3 -#define VMW_BALLOON_CMD_GUEST_ID 4 -#define VMW_BALLOON_CMD_BATCHED_LOCK 6 -#define VMW_BALLOON_CMD_BATCHED_UNLOCK 7 -#define VMW_BALLOON_CMD_BATCHED_2M_LOCK 8 -#define VMW_BALLOON_CMD_BATCHED_2M_UNLOCK 9 -#define VMW_BALLOON_CMD_VMCI_DOORBELL_SET 10 - - -/* error codes */ -#define VMW_BALLOON_SUCCESS 0 -#define VMW_BALLOON_FAILURE -1 -#define VMW_BALLOON_ERROR_CMD_INVALID 1 -#define VMW_BALLOON_ERROR_PPN_INVALID 2 -#define VMW_BALLOON_ERROR_PPN_LOCKED 3 -#define VMW_BALLOON_ERROR_PPN_UNLOCKED 4 -#define VMW_BALLOON_ERROR_PPN_PINNED 5 -#define VMW_BALLOON_ERROR_PPN_NOTNEEDED 6 -#define VMW_BALLOON_ERROR_RESET 7 -#define VMW_BALLOON_ERROR_BUSY 8 +enum vmballoon_page_size_type { + VMW_BALLOON_4K_PAGE, + VMW_BALLOON_2M_PAGE, + VMW_BALLOON_LAST_SIZE = VMW_BALLOON_2M_PAGE +}; -#define VMW_BALLOON_SUCCESS_WITH_CAPABILITIES (0x03000000) +#define VMW_BALLOON_NUM_PAGE_SIZES (VMW_BALLOON_LAST_SIZE + 1) -/* Batch page description */ +static const char * const vmballoon_page_size_names[] = { + [VMW_BALLOON_4K_PAGE] = "4k", + [VMW_BALLOON_2M_PAGE] = "2M" +}; -/* - * Layout of a page in the batch page: +enum vmballoon_op { + VMW_BALLOON_INFLATE, + VMW_BALLOON_DEFLATE +}; + +enum vmballoon_op_stat_type { + VMW_BALLOON_OP_STAT, + VMW_BALLOON_OP_FAIL_STAT +}; + +#define VMW_BALLOON_OP_STAT_TYPES (VMW_BALLOON_OP_FAIL_STAT + 1) + +/** + * enum vmballoon_cmd_type - backdoor commands. * - * +-------------+----------+--------+ - * | | | | - * | Page number | Reserved | Status | - * | | | | - * +-------------+----------+--------+ - * 64 PAGE_SHIFT 6 0 + * Availability of the commands is as followed: * - * The reserved field should be set to 0. + * %VMW_BALLOON_CMD_START, %VMW_BALLOON_CMD_GET_TARGET and + * %VMW_BALLOON_CMD_GUEST_ID are always available. + * + * If the host reports %VMW_BALLOON_BASIC_CMDS are supported then + * %VMW_BALLOON_CMD_LOCK and %VMW_BALLOON_CMD_UNLOCK commands are available. + * + * If the host reports %VMW_BALLOON_BATCHED_CMDS are supported then + * %VMW_BALLOON_CMD_BATCHED_LOCK and VMW_BALLOON_CMD_BATCHED_UNLOCK commands + * are available. + * + * If the host reports %VMW_BALLOON_BATCHED_2M_CMDS are supported then + * %VMW_BALLOON_CMD_BATCHED_2M_LOCK and %VMW_BALLOON_CMD_BATCHED_2M_UNLOCK + * are supported. + * + * If the host reports VMW_BALLOON_SIGNALLED_WAKEUP_CMD is supported then + * VMW_BALLOON_CMD_VMCI_DOORBELL_SET command is supported. + * + * @VMW_BALLOON_CMD_START: Communicating supported version with the hypervisor. + * @VMW_BALLOON_CMD_GET_TARGET: Gets the balloon target size. + * @VMW_BALLOON_CMD_LOCK: Informs the hypervisor about a ballooned page. + * @VMW_BALLOON_CMD_UNLOCK: Informs the hypervisor about a page that is about + * to be deflated from the balloon. + * @VMW_BALLOON_CMD_GUEST_ID: Informs the hypervisor about the type of OS that + * runs in the VM. + * @VMW_BALLOON_CMD_BATCHED_LOCK: Inform the hypervisor about a batch of + * ballooned pages (up to 512). + * @VMW_BALLOON_CMD_BATCHED_UNLOCK: Inform the hypervisor about a batch of + * pages that are about to be deflated from the + * balloon (up to 512). + * @VMW_BALLOON_CMD_BATCHED_2M_LOCK: Similar to @VMW_BALLOON_CMD_BATCHED_LOCK + * for 2MB pages. + * @VMW_BALLOON_CMD_BATCHED_2M_UNLOCK: Similar to + * @VMW_BALLOON_CMD_BATCHED_UNLOCK for 2MB + * pages. + * @VMW_BALLOON_CMD_VMCI_DOORBELL_SET: A command to set doorbell notification + * that would be invoked when the balloon + * size changes. + * @VMW_BALLOON_CMD_LAST: Value of the last command. */ -#define VMW_BALLOON_BATCH_MAX_PAGES (PAGE_SIZE / sizeof(u64)) -#define VMW_BALLOON_BATCH_STATUS_MASK ((1UL << 5) - 1) -#define VMW_BALLOON_BATCH_PAGE_MASK (~((1UL << PAGE_SHIFT) - 1)) - -struct vmballoon_batch_page { - u64 pages[VMW_BALLOON_BATCH_MAX_PAGES]; +enum vmballoon_cmd_type { + VMW_BALLOON_CMD_START, + VMW_BALLOON_CMD_GET_TARGET, + VMW_BALLOON_CMD_LOCK, + VMW_BALLOON_CMD_UNLOCK, + VMW_BALLOON_CMD_GUEST_ID, + /* No command 5 */ + VMW_BALLOON_CMD_BATCHED_LOCK = 6, + VMW_BALLOON_CMD_BATCHED_UNLOCK, + VMW_BALLOON_CMD_BATCHED_2M_LOCK, + VMW_BALLOON_CMD_BATCHED_2M_UNLOCK, + VMW_BALLOON_CMD_VMCI_DOORBELL_SET, + VMW_BALLOON_CMD_LAST = VMW_BALLOON_CMD_VMCI_DOORBELL_SET, }; -static u64 vmballoon_batch_get_pa(struct vmballoon_batch_page *batch, int idx) -{ - return batch->pages[idx] & VMW_BALLOON_BATCH_PAGE_MASK; -} +#define VMW_BALLOON_CMD_NUM (VMW_BALLOON_CMD_LAST + 1) + +enum vmballoon_error_codes { + VMW_BALLOON_SUCCESS, + VMW_BALLOON_ERROR_CMD_INVALID, + VMW_BALLOON_ERROR_PPN_INVALID, + VMW_BALLOON_ERROR_PPN_LOCKED, + VMW_BALLOON_ERROR_PPN_UNLOCKED, + VMW_BALLOON_ERROR_PPN_PINNED, + VMW_BALLOON_ERROR_PPN_NOTNEEDED, + VMW_BALLOON_ERROR_RESET, + VMW_BALLOON_ERROR_BUSY +}; -static int vmballoon_batch_get_status(struct vmballoon_batch_page *batch, - int idx) -{ - return (int)(batch->pages[idx] & VMW_BALLOON_BATCH_STATUS_MASK); -} +#define VMW_BALLOON_SUCCESS_WITH_CAPABILITIES (0x03000000) -static void vmballoon_batch_set_pa(struct vmballoon_batch_page *batch, int idx, - u64 pa) -{ - batch->pages[idx] = pa; -} +#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)) + +static const char * const vmballoon_cmd_names[] = { + [VMW_BALLOON_CMD_START] = "start", + [VMW_BALLOON_CMD_GET_TARGET] = "target", + [VMW_BALLOON_CMD_LOCK] = "lock", + [VMW_BALLOON_CMD_UNLOCK] = "unlock", + [VMW_BALLOON_CMD_GUEST_ID] = "guestType", + [VMW_BALLOON_CMD_BATCHED_LOCK] = "batchLock", + [VMW_BALLOON_CMD_BATCHED_UNLOCK] = "batchUnlock", + [VMW_BALLOON_CMD_BATCHED_2M_LOCK] = "2m-lock", + [VMW_BALLOON_CMD_BATCHED_2M_UNLOCK] = "2m-unlock", + [VMW_BALLOON_CMD_VMCI_DOORBELL_SET] = "doorbellSet" +}; +enum vmballoon_stat_page { + VMW_BALLOON_PAGE_STAT_ALLOC, + VMW_BALLOON_PAGE_STAT_ALLOC_FAIL, + VMW_BALLOON_PAGE_STAT_REFUSED_ALLOC, + VMW_BALLOON_PAGE_STAT_REFUSED_FREE, + VMW_BALLOON_PAGE_STAT_FREE, + VMW_BALLOON_PAGE_STAT_LAST = VMW_BALLOON_PAGE_STAT_FREE +}; -#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; \ -}) +#define VMW_BALLOON_PAGE_STAT_NUM (VMW_BALLOON_PAGE_STAT_LAST + 1) -#ifdef CONFIG_DEBUG_FS -struct vmballoon_stats { - unsigned int timer; - unsigned int doorbell; - - /* allocation statistics */ - unsigned int alloc[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int alloc_fail[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int sleep_alloc; - unsigned int sleep_alloc_fail; - unsigned int refused_alloc[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int refused_free[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int free[VMW_BALLOON_NUM_PAGE_SIZES]; - - /* monitor operations */ - unsigned int lock[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int lock_fail[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int unlock[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int unlock_fail[VMW_BALLOON_NUM_PAGE_SIZES]; - unsigned int target; - unsigned int target_fail; - unsigned int start; - unsigned int start_fail; - unsigned int guest_type; - unsigned int guest_type_fail; - unsigned int doorbell_set; - unsigned int doorbell_unset; +enum vmballoon_stat_general { + VMW_BALLOON_STAT_TIMER, + VMW_BALLOON_STAT_DOORBELL, + VMW_BALLOON_STAT_RESET, + VMW_BALLOON_STAT_LAST = VMW_BALLOON_STAT_RESET }; -#define STATS_INC(stat) (stat)++ -#else -#define STATS_INC(stat) -#endif +#define VMW_BALLOON_STAT_NUM (VMW_BALLOON_STAT_LAST + 1) -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); - int (*unlock)(struct vmballoon *b, unsigned int num_pages, - bool is_2m_pages, unsigned int *target); +static DEFINE_STATIC_KEY_TRUE(vmw_balloon_batching); +static DEFINE_STATIC_KEY_FALSE(balloon_stat_enabled); + +struct vmballoon_ctl { + struct list_head pages; + struct list_head refused_pages; + unsigned int n_refused_pages; + unsigned int n_pages; + enum vmballoon_page_size_type page_size; + enum vmballoon_op op; }; struct vmballoon_page_size { /* list of reserved physical pages */ struct list_head pages; - - /* transient list of non-balloonable pages */ - struct list_head refused_pages; - unsigned int n_refused_pages; }; +/** + * struct vmballoon_batch_entry - a batch entry for lock or unlock. + * + * @status: the status of the operation, which is written by the hypervisor. + * @reserved: reserved for future use. Must be set to zero. + * @pfn: the physical frame number of the page to be locked or unlocked. + */ +struct vmballoon_batch_entry { + u64 status : 5; + u64 reserved : PAGE_SHIFT - 5; + u64 pfn : 52; +} __packed; + struct vmballoon { struct vmballoon_page_size page_sizes[VMW_BALLOON_NUM_PAGE_SIZES]; - /* supported page sizes. 1 == 4k pages only, 2 == 4k and 2m pages */ - unsigned supported_page_sizes; + /** + * @max_page_size: maximum supported page size for ballooning. + * + * Protected by @conf_sem + */ + enum vmballoon_page_size_type max_page_size; + + /** + * @size: balloon actual size in basic page size (frames). + * + * While we currently do not support size which is bigger than 32-bit, + * in preparation for future support, use 64-bits. + */ + atomic64_t size; - /* balloon size in pages */ - unsigned int size; - unsigned int target; + /** + * @target: balloon target size in basic page size (frames). + * + * We do not protect the target under the assumption that setting the + * value is always done through a single write. If this assumption ever + * breaks, we would have to use X_ONCE for accesses, and suffer the less + * optimized code. Although we may read stale target value if multiple + * accesses happen at once, the performance impact should be minor. + */ + unsigned long target; - /* reset flag */ + /** + * @reset_required: reset flag + * + * Setting this flag may introduce races, but the code is expected to + * handle them gracefully. In the worst case, another operation will + * fail as reset did not take place. Clearing the flag is done while + * holding @conf_sem for write. + */ bool reset_required; + /** + * @capabilities: hypervisor balloon capabilities. + * + * Protected by @conf_sem. + */ unsigned long capabilities; - struct vmballoon_batch_page *batch_page; + /** + * @batch_page: pointer to communication batch page. + * + * When batching is used, batch_page points to a page, which holds up to + * %VMW_BALLOON_BATCH_MAX_PAGES entries for locking or unlocking. + */ + struct vmballoon_batch_entry *batch_page; + + /** + * @batch_max_pages: maximum pages that can be locked/unlocked. + * + * Indicates the number of pages that the hypervisor can lock or unlock + * at once, according to whether batching is enabled. If batching is + * disabled, only a single page can be locked/unlock on each operation. + * + * Protected by @conf_sem. + */ unsigned int batch_max_pages; - struct page *page; - const struct vmballoon_ops *ops; + /** + * @page: page to be locked/unlocked by the hypervisor + * + * @page is only used when batching is disabled and a single page is + * reclaimed on each iteration. + * + * Protected by @comm_lock. + */ + struct page *page; -#ifdef CONFIG_DEBUG_FS /* statistics */ - struct vmballoon_stats stats; + struct vmballoon_stats *stats; +#ifdef CONFIG_DEBUG_FS /* debugfs file exporting statistics */ struct dentry *dbg_entry; #endif - struct sysinfo sysinfo; - struct delayed_work dwork; + /** + * @vmci_doorbell. + * + * Protected by @conf_sem. + */ struct vmci_handle vmci_doorbell; + + /** + * @conf_sem: semaphore to protect the configuration and the statistics. + */ + struct rw_semaphore conf_sem; + + /** + * @comm_lock: lock to protect the communication with the host. + * + * Lock ordering: @conf_sem -> @comm_lock . + */ + spinlock_t comm_lock; }; static struct vmballoon balloon; +struct vmballoon_stats { + /* timer / doorbell operations */ + atomic64_t general_stat[VMW_BALLOON_STAT_NUM]; + + /* allocation statistics for huge and small pages */ + atomic64_t + page_stat[VMW_BALLOON_PAGE_STAT_NUM][VMW_BALLOON_NUM_PAGE_SIZES]; + + /* Monitor operations: total operations, and failures */ + atomic64_t ops[VMW_BALLOON_CMD_NUM][VMW_BALLOON_OP_STAT_TYPES]; +}; + +static inline bool is_vmballoon_stats_on(void) +{ + return IS_ENABLED(CONFIG_DEBUG_FS) && + static_branch_unlikely(&balloon_stat_enabled); +} + +static inline void vmballoon_stats_op_inc(struct vmballoon *b, unsigned int op, + enum vmballoon_op_stat_type type) +{ + if (is_vmballoon_stats_on()) + atomic64_inc(&b->stats->ops[op][type]); +} + +static inline void vmballoon_stats_gen_inc(struct vmballoon *b, + enum vmballoon_stat_general stat) +{ + if (is_vmballoon_stats_on()) + atomic64_inc(&b->stats->general_stat[stat]); +} + +static inline void vmballoon_stats_gen_add(struct vmballoon *b, + enum vmballoon_stat_general stat, + unsigned int val) +{ + if (is_vmballoon_stats_on()) + atomic64_add(val, &b->stats->general_stat[stat]); +} + +static inline void vmballoon_stats_page_inc(struct vmballoon *b, + enum vmballoon_stat_page stat, + enum vmballoon_page_size_type size) +{ + if (is_vmballoon_stats_on()) + atomic64_inc(&b->stats->page_stat[stat][size]); +} + +static inline void vmballoon_stats_page_add(struct vmballoon *b, + enum vmballoon_stat_page stat, + enum vmballoon_page_size_type size, + unsigned int val) +{ + if (is_vmballoon_stats_on()) + atomic64_add(val, &b->stats->page_stat[stat][size]); +} + +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; + + vmballoon_stats_op_inc(b, cmd, VMW_BALLOON_OP_STAT); + + 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)) + WRITE_ONCE(b->target, local_result); + + if (status != VMW_BALLOON_SUCCESS && + status != VMW_BALLOON_SUCCESS_WITH_CAPABILITIES) { + vmballoon_stats_op_inc(b, cmd, VMW_BALLOON_OP_FAIL_STAT); + pr_debug("%s: %s [0x%lx,0x%lx) failed, returned %ld\n", + __func__, vmballoon_cmd_names[cmd], arg1, arg2, + status); + } + + /* 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) +static int vmballoon_send_start(struct vmballoon *b, unsigned long req_caps) { - unsigned long status, capabilities, dummy = 0; - bool success; - - STATS_INC(b->stats.start); + unsigned long status, capabilities; - 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: b->capabilities = capabilities; - success = true; break; case VMW_BALLOON_SUCCESS: b->capabilities = VMW_BALLOON_BASIC_CMDS; - success = true; break; default: - success = false; + return -EIO; } /* @@ -303,626 +501,693 @@ static bool vmballoon_send_start(struct vmballoon *b, unsigned long req_caps) * reason disabled, do not use 2MB pages, since otherwise the legacy * mechanism is used with 2MB pages, causing a failure. */ + b->max_page_size = VMW_BALLOON_4K_PAGE; if ((b->capabilities & VMW_BALLOON_BATCHED_2M_CMDS) && (b->capabilities & VMW_BALLOON_BATCHED_CMDS)) - b->supported_page_sizes = 2; - else - b->supported_page_sizes = 1; - - if (!success) { - pr_debug("%s - failed, hv returns %ld\n", __func__, status); - STATS_INC(b->stats.start_fail); - } - return success; -} + b->max_page_size = VMW_BALLOON_2M_PAGE; -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; - } + return 0; } -/* +/** + * vmballoon_send_guest_id - communicate guest type to the host. + * + * @b: pointer to the balloon. + * * Communicate guest type to the host so that it can adjust ballooning * algorithm to the one most appropriate for the guest. This command * is normally issued after sending "start" command and is part of * standard reset sequence. + * + * Return: zero on success or appropriate error code. */ -static bool vmballoon_send_guest_id(struct vmballoon *b) +static int vmballoon_send_guest_id(struct vmballoon *b) { - unsigned long status, dummy = 0; - - status = VMWARE_BALLOON_CMD(GUEST_ID, VMW_BALLOON_GUEST_ID, dummy, - dummy); - - STATS_INC(b->stats.guest_type); + unsigned long status; - if (vmballoon_check_status(b, status)) - return true; + status = vmballoon_cmd(b, VMW_BALLOON_CMD_GUEST_ID, + VMW_BALLOON_GUEST_ID, 0); - pr_debug("%s - failed, hv returns %ld\n", __func__, status); - STATS_INC(b->stats.guest_type_fail); - return false; + return status == VMW_BALLOON_SUCCESS ? 0 : -EIO; } -static u16 vmballoon_page_size(bool is_2m_page) +/** + * vmballoon_page_order() - return the order of the page + * @page_size: the size of the page. + * + * Return: the allocation order. + */ +static inline +unsigned int vmballoon_page_order(enum vmballoon_page_size_type page_size) { - if (is_2m_page) - return 1 << VMW_BALLOON_2M_SHIFT; + return page_size == VMW_BALLOON_2M_PAGE ? VMW_BALLOON_2M_ORDER : 0; +} - return 1; +/** + * vmballoon_page_in_frames() - returns the number of frames in a page. + * @page_size: the size of the page. + * + * Return: the number of 4k frames. + */ +static inline unsigned int +vmballoon_page_in_frames(enum vmballoon_page_size_type page_size) +{ + return 1 << vmballoon_page_order(page_size); } -/* - * Retrieve desired balloon size from the host. +/** + * vmballoon_send_get_target() - Retrieve desired balloon size from the host. + * + * @b: pointer to the balloon. + * + * Return: zero on success, EINVAL if limit does not fit in 32-bit, as required + * by the host-guest protocol and EIO if an error occurred in communicating with + * the host. */ -static bool vmballoon_send_get_target(struct vmballoon *b, u32 *new_target) +static int vmballoon_send_get_target(struct vmballoon *b) { unsigned long status; - unsigned long target; unsigned long limit; - unsigned long dummy = 0; - u32 limit32; - /* - * si_meminfo() is cheap. Moreover, we want to provide dynamic - * max balloon size later. So let us call si_meminfo() every - * iteration. - */ - si_meminfo(&b->sysinfo); - limit = b->sysinfo.totalram; + limit = totalram_pages; /* Ensure limit fits in 32-bits */ - limit32 = (u32)limit; - if (limit != limit32) - return false; - - /* update stats */ - STATS_INC(b->stats.target); + if (limit != (u32)limit) + return -EINVAL; - status = VMWARE_BALLOON_CMD(GET_TARGET, limit, dummy, target); - if (vmballoon_check_status(b, status)) { - *new_target = target; - return true; - } + status = vmballoon_cmd(b, VMW_BALLOON_CMD_GET_TARGET, limit, 0); - pr_debug("%s - failed, hv returns %ld\n", __func__, status); - STATS_INC(b->stats.target_fail); - return false; + return status == VMW_BALLOON_SUCCESS ? 0 : -EIO; } -/* - * Notify the host about allocated page so that host can use it without - * fear that guest will need it. Host may reject some pages, we need to - * check the return value and maybe submit a different page. +/** + * vmballoon_alloc_page_list - allocates a list of pages. + * + * @b: pointer to the balloon. + * @ctl: pointer for the %struct vmballoon_ctl, which defines the operation. + * @req_n_pages: the number of requested pages. + * + * Tries to allocate @req_n_pages. Add them to the list of balloon pages in + * @ctl.pages and updates @ctl.n_pages to reflect the number of pages. + * + * Return: zero on success or error code otherwise. */ -static int vmballoon_send_lock_page(struct vmballoon *b, unsigned long pfn, - unsigned int *hv_status, unsigned int *target) +static int vmballoon_alloc_page_list(struct vmballoon *b, + struct vmballoon_ctl *ctl, + unsigned int req_n_pages) { - unsigned long status, dummy = 0; - u32 pfn32; - - pfn32 = (u32)pfn; - if (pfn32 != pfn) - return -EINVAL; - - STATS_INC(b->stats.lock[false]); + struct page *page; + unsigned int i; - *hv_status = status = VMWARE_BALLOON_CMD(LOCK, pfn, dummy, *target); - if (vmballoon_check_status(b, status)) - return 0; + for (i = 0; i < req_n_pages; i++) { + if (ctl->page_size == VMW_BALLOON_2M_PAGE) + page = alloc_pages(VMW_HUGE_PAGE_ALLOC_FLAGS, + VMW_BALLOON_2M_ORDER); + else + page = alloc_page(VMW_PAGE_ALLOC_FLAGS); - pr_debug("%s - ppn %lx, hv returns %ld\n", __func__, pfn, status); - STATS_INC(b->stats.lock_fail[false]); - return -EIO; -} + /* Update statistics */ + vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_ALLOC, + ctl->page_size); -static int vmballoon_send_batched_lock(struct vmballoon *b, - unsigned int num_pages, bool is_2m_pages, unsigned int *target) -{ - unsigned long status; - unsigned long pfn = PHYS_PFN(virt_to_phys(b->batch_page)); + if (page) { + /* Success. Add the page to the list and continue. */ + list_add(&page->lru, &ctl->pages); + continue; + } - STATS_INC(b->stats.lock[is_2m_pages]); + /* Allocation failed. Update statistics and stop. */ + vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_ALLOC_FAIL, + ctl->page_size); + break; + } - 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); + ctl->n_pages = i; - if (vmballoon_check_status(b, status)) - return 0; - - pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status); - STATS_INC(b->stats.lock_fail[is_2m_pages]); - return 1; + return req_n_pages == ctl->n_pages ? 0 : -ENOMEM; } -/* - * Notify the host that guest intends to release given page back into - * the pool of available (to the guest) pages. +/** + * vmballoon_handle_one_result - Handle lock/unlock result for a single page. + * + * @b: pointer for %struct vmballoon. + * @page: pointer for the page whose result should be handled. + * @page_size: size of the page. + * @status: status of the operation as provided by the hypervisor. */ -static bool vmballoon_send_unlock_page(struct vmballoon *b, unsigned long pfn, - unsigned int *target) +static int vmballoon_handle_one_result(struct vmballoon *b, struct page *page, + enum vmballoon_page_size_type page_size, + unsigned long status) { - unsigned long status, dummy = 0; - u32 pfn32; - - pfn32 = (u32)pfn; - if (pfn32 != pfn) - return false; + /* On success do nothing. The page is already on the balloon list. */ + if (likely(status == VMW_BALLOON_SUCCESS)) + return 0; - STATS_INC(b->stats.unlock[false]); + pr_debug("%s: failed comm pfn %lx status %lu page_size %s\n", __func__, + page_to_pfn(page), status, + vmballoon_page_size_names[page_size]); - status = VMWARE_BALLOON_CMD(UNLOCK, pfn, dummy, *target); - if (vmballoon_check_status(b, status)) - return true; + /* Error occurred */ + vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_REFUSED_ALLOC, + page_size); - pr_debug("%s - ppn %lx, hv returns %ld\n", __func__, pfn, status); - STATS_INC(b->stats.unlock_fail[false]); - return false; + return -EIO; } -static bool vmballoon_send_batched_unlock(struct vmballoon *b, - unsigned int num_pages, bool is_2m_pages, unsigned int *target) +/** + * vmballoon_status_page - returns the status of (un)lock operation + * + * @b: pointer to the balloon. + * @idx: index for the page for which the operation is performed. + * @p: pointer to where the page struct is returned. + * + * Following a lock or unlock operation, returns the status of the operation for + * an individual page. Provides the page that the operation was performed on on + * the @page argument. + * + * Returns: The status of a lock or unlock operation for an individual page. + */ +static unsigned long vmballoon_status_page(struct vmballoon *b, int idx, + struct page **p) { - unsigned long status; - unsigned long pfn = PHYS_PFN(virt_to_phys(b->batch_page)); - - 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); + if (static_branch_likely(&vmw_balloon_batching)) { + /* batching mode */ + *p = pfn_to_page(b->batch_page[idx].pfn); + return b->batch_page[idx].status; + } - if (vmballoon_check_status(b, status)) - return true; + /* non-batching mode */ + *p = b->page; - pr_debug("%s - batch ppn %lx, hv returns %ld\n", __func__, pfn, status); - STATS_INC(b->stats.unlock_fail[is_2m_pages]); - return false; + /* + * If a failure occurs, the indication will be provided in the status + * of the entire operation, which is considered before the individual + * page status. So for non-batching mode, the indication is always of + * success. + */ + return VMW_BALLOON_SUCCESS; } -static struct page *vmballoon_alloc_page(gfp_t flags, bool is_2m_page) +/** + * vmballoon_lock_op - notifies the host about inflated/deflated pages. + * @b: pointer to the balloon. + * @num_pages: number of inflated/deflated pages. + * @page_size: size of the page. + * @op: the type of operation (lock or unlock). + * + * Notify the host about page(s) that were ballooned (or removed from the + * balloon) so that host can use it without fear that guest will need it (or + * stop using them since the VM does). Host may reject some pages, we need to + * check the return value and maybe submit a different page. The pages that are + * inflated/deflated are pointed by @b->page. + * + * Return: result as provided by the hypervisor. + */ +static unsigned long vmballoon_lock_op(struct vmballoon *b, + unsigned int num_pages, + enum vmballoon_page_size_type page_size, + enum vmballoon_op op) { - if (is_2m_page) - return alloc_pages(flags, VMW_BALLOON_2M_SHIFT); + unsigned long cmd, pfn; - return alloc_page(flags); -} + lockdep_assert_held(&b->comm_lock); -static void vmballoon_free_page(struct page *page, bool is_2m_page) -{ - if (is_2m_page) - __free_pages(page, VMW_BALLOON_2M_SHIFT); - else - __free_page(page); + if (static_branch_likely(&vmw_balloon_batching)) { + if (op == VMW_BALLOON_INFLATE) + cmd = page_size == VMW_BALLOON_2M_PAGE ? + VMW_BALLOON_CMD_BATCHED_2M_LOCK : + VMW_BALLOON_CMD_BATCHED_LOCK; + else + cmd = page_size == VMW_BALLOON_2M_PAGE ? + VMW_BALLOON_CMD_BATCHED_2M_UNLOCK : + VMW_BALLOON_CMD_BATCHED_UNLOCK; + + pfn = PHYS_PFN(virt_to_phys(b->batch_page)); + } else { + cmd = op == VMW_BALLOON_INFLATE ? VMW_BALLOON_CMD_LOCK : + VMW_BALLOON_CMD_UNLOCK; + pfn = page_to_pfn(b->page); + + /* In non-batching mode, PFNs must fit in 32-bit */ + if (unlikely(pfn != (u32)pfn)) + return VMW_BALLOON_ERROR_PPN_INVALID; + } + + return vmballoon_cmd(b, cmd, pfn, num_pages); } -/* - * Quickly release all pages allocated for the balloon. This function is - * called when host decides to "reset" balloon for one reason or another. - * Unlike normal "deflate" we do not (shall not) notify host of the pages - * being released. +/** + * vmballoon_add_page - adds a page towards lock/unlock operation. + * + * @b: pointer to the balloon. + * @idx: index of the page to be ballooned in this batch. + * @p: pointer to the page that is about to be ballooned. + * + * Adds the page to be ballooned. Must be called while holding @comm_lock. */ -static void vmballoon_pop(struct vmballoon *b) +static void vmballoon_add_page(struct vmballoon *b, unsigned int idx, + struct page *p) { - struct page *page, *next; - unsigned is_2m_pages; - - for (is_2m_pages = 0; is_2m_pages < VMW_BALLOON_NUM_PAGE_SIZES; - is_2m_pages++) { - struct vmballoon_page_size *page_size = - &b->page_sizes[is_2m_pages]; - u16 size_per_page = vmballoon_page_size(is_2m_pages); - - list_for_each_entry_safe(page, next, &page_size->pages, lru) { - list_del(&page->lru); - vmballoon_free_page(page, is_2m_pages); - STATS_INC(b->stats.free[is_2m_pages]); - b->size -= size_per_page; - cond_resched(); - } - } + lockdep_assert_held(&b->comm_lock); - /* Clearing the batch_page unconditionally has no adverse effect */ - free_page((unsigned long)b->batch_page); - b->batch_page = NULL; + if (static_branch_likely(&vmw_balloon_batching)) + b->batch_page[idx] = (struct vmballoon_batch_entry) + { .pfn = page_to_pfn(p) }; + else + b->page = p; } -/* - * Notify the host of a ballooned page. If host rejects the page put it on the - * refuse list, those refused page are then released at the end of the - * inflation cycle. +/** + * vmballoon_lock - lock or unlock a batch of pages. + * + * @b: pointer to the balloon. + * @ctl: pointer for the %struct vmballoon_ctl, which defines the operation. + * + * Notifies the host of about ballooned pages (after inflation or deflation, + * according to @ctl). If the host rejects the page put it on the + * @ctl refuse list. These refused page are then released when moving to the + * next size of pages. + * + * Note that we neither free any @page here nor put them back on the ballooned + * pages list. Instead we queue it for later processing. We do that for several + * reasons. First, we do not want to free the page under the lock. Second, it + * allows us to unify the handling of lock and unlock. In the inflate case, the + * caller will check if there are too many refused pages and release them. + * Although it is not identical to the past behavior, it should not affect + * performance. */ -static int vmballoon_lock_page(struct vmballoon *b, unsigned int num_pages, - bool is_2m_pages, unsigned int *target) +static int vmballoon_lock(struct vmballoon *b, struct vmballoon_ctl *ctl) { - int locked, hv_status; - 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 */ - - locked = vmballoon_send_lock_page(b, page_to_pfn(page), &hv_status, - target); - if (locked) { - STATS_INC(b->stats.refused_alloc[false]); - - if (locked == -EIO && - (hv_status == VMW_BALLOON_ERROR_RESET || - hv_status == VMW_BALLOON_ERROR_PPN_NOTNEEDED)) { - vmballoon_free_page(page, false); - return -EIO; - } - - /* - * Place page on the list of non-balloonable pages - * and retry allocation, unless we already accumulated - * too many of them, in which case take a breather. - */ - if (page_size->n_refused_pages < VMW_BALLOON_MAX_REFUSED) { - page_size->n_refused_pages++; - list_add(&page->lru, &page_size->refused_pages); - } else { - vmballoon_free_page(page, false); - } - return locked; - } - - /* track allocated page */ - list_add(&page->lru, &page_size->pages); + unsigned long batch_status; + struct page *page; + unsigned int i, num_pages; - /* update balloon size */ - b->size++; + num_pages = ctl->n_pages; + if (num_pages == 0) + return 0; - return 0; -} + /* communication with the host is done under the communication lock */ + spin_lock(&b->comm_lock); -static int vmballoon_lock_batched_page(struct vmballoon *b, - unsigned int num_pages, bool is_2m_pages, unsigned int *target) -{ - int locked, i; - u16 size_per_page = vmballoon_page_size(is_2m_pages); + i = 0; + list_for_each_entry(page, &ctl->pages, lru) + vmballoon_add_page(b, i++, page); - locked = vmballoon_send_batched_lock(b, num_pages, is_2m_pages, - target); - if (locked > 0) { - for (i = 0; i < num_pages; i++) { - u64 pa = vmballoon_batch_get_pa(b->batch_page, i); - struct page *p = pfn_to_page(pa >> PAGE_SHIFT); + batch_status = vmballoon_lock_op(b, ctl->n_pages, ctl->page_size, + ctl->op); - vmballoon_free_page(p, is_2m_pages); - } + /* + * Iterate over the pages in the provided list. Since we are changing + * @ctl->n_pages we are saving the original value in @num_pages and + * use this value to bound the loop. + */ + for (i = 0; i < num_pages; i++) { + unsigned long status; - return -EIO; - } + status = vmballoon_status_page(b, i, &page); - for (i = 0; i < num_pages; i++) { - u64 pa = vmballoon_batch_get_pa(b->batch_page, i); - struct page *p = pfn_to_page(pa >> PAGE_SHIFT); - struct vmballoon_page_size *page_size = - &b->page_sizes[is_2m_pages]; + /* + * Failure of the whole batch overrides a single operation + * results. + */ + if (batch_status != VMW_BALLOON_SUCCESS) + status = batch_status; - locked = vmballoon_batch_get_status(b->batch_page, i); + /* Continue if no error happened */ + if (!vmballoon_handle_one_result(b, page, ctl->page_size, + status)) + continue; - switch (locked) { - case VMW_BALLOON_SUCCESS: - list_add(&p->lru, &page_size->pages); - b->size += size_per_page; - break; - case VMW_BALLOON_ERROR_PPN_PINNED: - case VMW_BALLOON_ERROR_PPN_INVALID: - if (page_size->n_refused_pages - < VMW_BALLOON_MAX_REFUSED) { - list_add(&p->lru, &page_size->refused_pages); - page_size->n_refused_pages++; - break; - } - /* Fallthrough */ - case VMW_BALLOON_ERROR_RESET: - case VMW_BALLOON_ERROR_PPN_NOTNEEDED: - vmballoon_free_page(p, is_2m_pages); - break; - default: - /* This should never happen */ - WARN_ON_ONCE(true); - } + /* + * Error happened. Move the pages to the refused list and update + * the pages number. + */ + list_move(&page->lru, &ctl->refused_pages); + ctl->n_pages--; + ctl->n_refused_pages++; } - return 0; + spin_unlock(&b->comm_lock); + + return batch_status == VMW_BALLOON_SUCCESS ? 0 : -EIO; } -/* - * Release the page allocated for the balloon. Note that we first notify - * the host so it can make sure the page will be available for the guest - * to use, if needed. +/** + * vmballoon_release_page_list() - Releases a page list + * + * @page_list: list of pages to release. + * @n_pages: pointer to the number of pages. + * @page_size: whether the pages in the list are 2MB (or else 4KB). + * + * Releases the list of pages and zeros the number of pages. */ -static int vmballoon_unlock_page(struct vmballoon *b, unsigned int num_pages, - bool is_2m_pages, unsigned int *target) +static void vmballoon_release_page_list(struct list_head *page_list, + int *n_pages, + enum vmballoon_page_size_type page_size) { - 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 */ + struct page *page, *tmp; - if (!vmballoon_send_unlock_page(b, page_to_pfn(page), target)) { - list_add(&page->lru, &page_size->pages); - return -EIO; + list_for_each_entry_safe(page, tmp, page_list, lru) { + list_del(&page->lru); + __free_pages(page, vmballoon_page_order(page_size)); } - /* deallocate page */ - vmballoon_free_page(page, false); - STATS_INC(b->stats.free[false]); + *n_pages = 0; +} - /* update balloon size */ - b->size--; - return 0; +/* + * Release pages that were allocated while attempting to inflate the + * balloon but were refused by the host for one reason or another. + */ +static void vmballoon_release_refused_pages(struct vmballoon *b, + struct vmballoon_ctl *ctl) +{ + vmballoon_stats_page_inc(b, VMW_BALLOON_PAGE_STAT_REFUSED_FREE, + ctl->page_size); + + vmballoon_release_page_list(&ctl->refused_pages, &ctl->n_refused_pages, + ctl->page_size); } -static int vmballoon_unlock_batched_page(struct vmballoon *b, - unsigned int num_pages, bool is_2m_pages, - unsigned int *target) +/** + * vmballoon_change - retrieve the required balloon change + * + * @b: pointer for the balloon. + * + * Return: the required change for the balloon size. A positive number + * indicates inflation, a negative number indicates a deflation. + */ +static int64_t vmballoon_change(struct vmballoon *b) { - int locked, i, ret = 0; - bool hv_success; - u16 size_per_page = vmballoon_page_size(is_2m_pages); + int64_t size, target; - hv_success = vmballoon_send_batched_unlock(b, num_pages, is_2m_pages, - target); - if (!hv_success) - ret = -EIO; + size = atomic64_read(&b->size); + target = READ_ONCE(b->target); - for (i = 0; i < num_pages; i++) { - u64 pa = vmballoon_batch_get_pa(b->batch_page, i); - struct page *p = pfn_to_page(pa >> PAGE_SHIFT); - struct vmballoon_page_size *page_size = - &b->page_sizes[is_2m_pages]; + /* + * We must cast first because of int sizes + * Otherwise we might get huge positives instead of negatives + */ - locked = vmballoon_batch_get_status(b->batch_page, i); - if (!hv_success || locked != VMW_BALLOON_SUCCESS) { - /* - * That page wasn't successfully unlocked by the - * hypervisor, re-add it to the list of pages owned by - * the balloon driver. - */ - list_add(&p->lru, &page_size->pages); - } else { - /* deallocate page */ - vmballoon_free_page(p, is_2m_pages); - STATS_INC(b->stats.free[is_2m_pages]); - - /* update balloon size */ - b->size -= size_per_page; - } - } + if (b->reset_required) + return 0; + + /* consider a 2MB slack on deflate, unless the balloon is emptied */ + if (target < size && target != 0 && + size - target < vmballoon_page_in_frames(VMW_BALLOON_2M_PAGE)) + return 0; - return ret; + return target - size; } -/* - * Release pages that were allocated while attempting to inflate the - * balloon but were refused by the host for one reason or another. +/** + * vmballoon_enqueue_page_list() - Enqueues list of pages after inflation. + * + * @b: pointer to balloon. + * @pages: list of pages to enqueue. + * @n_pages: pointer to number of pages in list. The value is zeroed. + * @page_size: whether the pages are 2MB or 4KB pages. + * + * Enqueues the provides list of pages in the ballooned page list, clears the + * list and zeroes the number of pages that was provided. */ -static void vmballoon_release_refused_pages(struct vmballoon *b, - bool is_2m_pages) +static void vmballoon_enqueue_page_list(struct vmballoon *b, + struct list_head *pages, + unsigned int *n_pages, + enum vmballoon_page_size_type page_size) { - struct page *page, *next; - struct vmballoon_page_size *page_size = - &b->page_sizes[is_2m_pages]; + struct vmballoon_page_size *page_size_info = &b->page_sizes[page_size]; - list_for_each_entry_safe(page, next, &page_size->refused_pages, lru) { - list_del(&page->lru); - vmballoon_free_page(page, is_2m_pages); - STATS_INC(b->stats.refused_free[is_2m_pages]); - } - - page_size->n_refused_pages = 0; + list_splice_init(pages, &page_size_info->pages); + *n_pages = 0; } -static void vmballoon_add_page(struct vmballoon *b, int idx, struct page *p) +/** + * vmballoon_dequeue_page_list() - Dequeues page lists for deflation. + * + * @b: pointer to balloon. + * @pages: list of pages to enqueue. + * @n_pages: pointer to number of pages in list. The value is zeroed. + * @page_size: whether the pages are 2MB or 4KB pages. + * @n_req_pages: the number of requested pages. + * + * Dequeues the number of requested pages from the balloon for deflation. The + * number of dequeued pages may be lower, if not enough pages in the requested + * size are available. + */ +static void vmballoon_dequeue_page_list(struct vmballoon *b, + struct list_head *pages, + unsigned int *n_pages, + enum vmballoon_page_size_type page_size, + unsigned int n_req_pages) { - b->page = p; -} + struct vmballoon_page_size *page_size_info = &b->page_sizes[page_size]; + struct page *page, *tmp; + unsigned int i = 0; -static void vmballoon_add_batched_page(struct vmballoon *b, int idx, - struct page *p) -{ - vmballoon_batch_set_pa(b->batch_page, idx, - (u64)page_to_pfn(p) << PAGE_SHIFT); + list_for_each_entry_safe(page, tmp, &page_size_info->pages, lru) { + list_move(&page->lru, pages); + if (++i == n_req_pages) + break; + } + *n_pages = i; } -/* - * Inflate the balloon towards its target size. Note that we try to limit - * the rate of allocation to make sure we are not choking the rest of the - * system. +/** + * vmballoon_inflate() - Inflate the balloon towards its target size. + * + * @b: pointer to the balloon. */ static void vmballoon_inflate(struct vmballoon *b) { - unsigned int num_pages = 0; - int error = 0; - gfp_t flags = VMW_PAGE_ALLOC_NOSLEEP; - bool is_2m_pages; + int64_t to_inflate_frames; + struct vmballoon_ctl ctl = { + .pages = LIST_HEAD_INIT(ctl.pages), + .refused_pages = LIST_HEAD_INIT(ctl.refused_pages), + .page_size = b->max_page_size, + .op = VMW_BALLOON_INFLATE + }; - pr_debug("%s - size: %d, target %d\n", __func__, b->size, b->target); + while ((to_inflate_frames = vmballoon_change(b)) > 0) { + unsigned int to_inflate_pages, page_in_frames; + int alloc_error, lock_error = 0; - /* - * First try NOSLEEP page allocations to inflate balloon. - * - * If we do not throttle nosleep allocations, we can drain all - * free pages in the guest quickly (if the balloon target is high). - * As a side-effect, draining free pages helps to inform (force) - * the guest to start swapping if balloon target is not met yet, - * which is a desired behavior. However, balloon driver can consume - * all available CPU cycles if too many pages are allocated in a - * second. Therefore, we throttle nosleep allocations even when - * the guest is not under memory pressure. OTOH, if we have already - * predicted that the guest is under memory pressure, then we - * slowdown page allocations considerably. - */ + VM_BUG_ON(!list_empty(&ctl.pages)); + VM_BUG_ON(ctl.n_pages != 0); - /* - * Start with no sleep allocation rate which may be higher - * than sleeping allocation rate. - */ - is_2m_pages = b->supported_page_sizes == VMW_BALLOON_NUM_PAGE_SIZES; + page_in_frames = vmballoon_page_in_frames(ctl.page_size); - pr_debug("%s - goal: %d", __func__, b->target - b->size); + to_inflate_pages = min_t(unsigned long, b->batch_max_pages, + DIV_ROUND_UP_ULL(to_inflate_frames, + page_in_frames)); - while (!b->reset_required && - b->size + num_pages * vmballoon_page_size(is_2m_pages) - < b->target) { - struct page *page; + /* Start by allocating */ + alloc_error = vmballoon_alloc_page_list(b, &ctl, + to_inflate_pages); - if (flags == VMW_PAGE_ALLOC_NOSLEEP) - STATS_INC(b->stats.alloc[is_2m_pages]); - else - STATS_INC(b->stats.sleep_alloc); - - page = vmballoon_alloc_page(flags, is_2m_pages); - if (!page) { - STATS_INC(b->stats.alloc_fail[is_2m_pages]); - - if (is_2m_pages) { - b->ops->lock(b, num_pages, true, &b->target); - - /* - * ignore errors from locking as we now switch - * to 4k pages and we might get different - * errors. - */ - - num_pages = 0; - is_2m_pages = false; - continue; - } - - if (flags == VMW_PAGE_ALLOC_CANSLEEP) { - /* - * CANSLEEP page allocation failed, so guest - * is under severe memory pressure. We just log - * the event, but do not stop the inflation - * due to its negative impact on performance. - */ - STATS_INC(b->stats.sleep_alloc_fail); + /* Actually lock the pages by telling the hypervisor */ + lock_error = vmballoon_lock(b, &ctl); + + /* + * If an error indicates that something serious went wrong, + * stop the inflation. + */ + if (lock_error) + break; + + /* Update the balloon size */ + atomic64_add(ctl.n_pages * page_in_frames, &b->size); + + vmballoon_enqueue_page_list(b, &ctl.pages, &ctl.n_pages, + ctl.page_size); + + /* + * If allocation failed or the number of refused pages exceeds + * the maximum allowed, move to the next page size. + */ + if (alloc_error || + ctl.n_refused_pages >= VMW_BALLOON_MAX_REFUSED) { + if (ctl.page_size == VMW_BALLOON_4K_PAGE) break; - } /* - * NOSLEEP page allocation failed, so the guest is - * under memory pressure. Slowing down page alloctions - * seems to be reasonable, but doing so might actually - * cause the hypervisor to throttle us down, resulting - * in degraded performance. We will count on the - * scheduler and standard memory management mechanisms - * for now. + * Ignore errors from locking as we now switch to 4k + * pages and we might get different errors. */ - flags = VMW_PAGE_ALLOC_CANSLEEP; - continue; - } - - 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); - num_pages = 0; - if (error) - break; + vmballoon_release_refused_pages(b, &ctl); + ctl.page_size--; } cond_resched(); } - if (num_pages > 0) - b->ops->lock(b, num_pages, is_2m_pages, &b->target); - - vmballoon_release_refused_pages(b, true); - vmballoon_release_refused_pages(b, false); + /* + * Release pages that were allocated while attempting to inflate the + * balloon but were refused by the host for one reason or another, + * and update the statistics. + */ + if (ctl.n_refused_pages != 0) + vmballoon_release_refused_pages(b, &ctl); } -/* +/** + * vmballoon_deflate() - Decrease the size of the balloon. + * + * @b: pointer to the balloon + * @n_frames: the number of frames to deflate. If zero, automatically + * calculated according to the target size. + * @coordinated: whether to coordinate with the host + * * Decrease the size of the balloon allowing guest to use more memory. + * + * Return: The number of deflated frames (i.e., basic page size units) */ -static void vmballoon_deflate(struct vmballoon *b) +static unsigned long vmballoon_deflate(struct vmballoon *b, uint64_t n_frames, + bool coordinated) { - unsigned is_2m_pages; - - pr_debug("%s - size: %d, target %d\n", __func__, b->size, b->target); + unsigned long deflated_frames = 0; + unsigned long tried_frames = 0; + struct vmballoon_ctl ctl = { + .pages = LIST_HEAD_INIT(ctl.pages), + .refused_pages = LIST_HEAD_INIT(ctl.refused_pages), + .page_size = VMW_BALLOON_4K_PAGE, + .op = VMW_BALLOON_DEFLATE + }; /* free pages to reach target */ - for (is_2m_pages = 0; is_2m_pages < b->supported_page_sizes; - is_2m_pages++) { - struct page *page, *next; - unsigned int num_pages = 0; - struct vmballoon_page_size *page_size = - &b->page_sizes[is_2m_pages]; - - list_for_each_entry_safe(page, next, &page_size->pages, lru) { - if (b->reset_required || - (b->target > 0 && - b->size - num_pages - * vmballoon_page_size(is_2m_pages) - < b->target + vmballoon_page_size(true))) - break; + while (true) { + unsigned int to_deflate_pages, n_unlocked_frames; + unsigned int page_in_frames; + int64_t to_deflate_frames; + bool deflated_all; + + page_in_frames = vmballoon_page_in_frames(ctl.page_size); + + VM_BUG_ON(!list_empty(&ctl.pages)); + VM_BUG_ON(ctl.n_pages); + VM_BUG_ON(!list_empty(&ctl.refused_pages)); + VM_BUG_ON(ctl.n_refused_pages); + + /* + * If we were requested a specific number of frames, we try to + * deflate this number of frames. Otherwise, deflation is + * performed according to the target and balloon size. + */ + to_deflate_frames = n_frames ? n_frames - tried_frames : + -vmballoon_change(b); + + /* break if no work to do */ + if (to_deflate_frames <= 0) + break; + + /* + * Calculate the number of frames based on current page size, + * but limit the deflated frames to a single chunk + */ + to_deflate_pages = min_t(unsigned long, b->batch_max_pages, + DIV_ROUND_UP_ULL(to_deflate_frames, + page_in_frames)); + + /* First take the pages from the balloon pages. */ + vmballoon_dequeue_page_list(b, &ctl.pages, &ctl.n_pages, + ctl.page_size, to_deflate_pages); + + /* + * Before pages are moving to the refused list, count their + * frames as frames that we tried to deflate. + */ + tried_frames += ctl.n_pages * page_in_frames; + + /* + * Unlock the pages by communicating with the hypervisor if the + * communication is coordinated (i.e., not pop). We ignore the + * return code. Instead we check if all the pages we manage to + * unlock all the pages. If we failed, we will move to the next + * page size, and would eventually try again later. + */ + if (coordinated) + vmballoon_lock(b, &ctl); + + /* + * Check if we deflated enough. We will move to the next page + * size if we did not manage to do so. This calculation takes + * place now, as once the pages are released, the number of + * pages is zeroed. + */ + deflated_all = (ctl.n_pages == to_deflate_pages); + + /* Update local and global counters */ + n_unlocked_frames = ctl.n_pages * page_in_frames; + atomic64_sub(n_unlocked_frames, &b->size); + deflated_frames += n_unlocked_frames; - list_del(&page->lru); - b->ops->add_page(b, num_pages++, page); + vmballoon_stats_page_add(b, VMW_BALLOON_PAGE_STAT_FREE, + ctl.page_size, ctl.n_pages); - if (num_pages == b->batch_max_pages) { - int error; + /* free the ballooned pages */ + vmballoon_release_page_list(&ctl.pages, &ctl.n_pages, + ctl.page_size); - error = b->ops->unlock(b, num_pages, - is_2m_pages, &b->target); - num_pages = 0; - if (error) - return; - } + /* Return the refused pages to the ballooned list. */ + vmballoon_enqueue_page_list(b, &ctl.refused_pages, + &ctl.n_refused_pages, + ctl.page_size); - cond_resched(); + /* If we failed to unlock all the pages, move to next size. */ + if (!deflated_all) { + if (ctl.page_size == b->max_page_size) + break; + ctl.page_size++; } - if (num_pages > 0) - b->ops->unlock(b, num_pages, is_2m_pages, &b->target); + cond_resched(); } -} -static const struct vmballoon_ops vmballoon_basic_ops = { - .add_page = vmballoon_add_page, - .lock = vmballoon_lock_page, - .unlock = vmballoon_unlock_page -}; + return deflated_frames; +} -static const struct vmballoon_ops vmballoon_batched_ops = { - .add_page = vmballoon_add_batched_page, - .lock = vmballoon_lock_batched_page, - .unlock = vmballoon_unlock_batched_page -}; +/** + * vmballoon_deinit_batching - disables batching mode. + * + * @b: pointer to &struct vmballoon. + * + * Disables batching, by deallocating the page for communication with the + * hypervisor and disabling the static key to indicate that batching is off. + */ +static void vmballoon_deinit_batching(struct vmballoon *b) +{ + free_page((unsigned long)b->batch_page); + b->batch_page = NULL; + static_branch_disable(&vmw_balloon_batching); + b->batch_max_pages = 1; +} -static bool vmballoon_init_batching(struct vmballoon *b) +/** + * vmballoon_init_batching - enable batching mode. + * + * @b: pointer to &struct vmballoon. + * + * Enables batching, by allocating a page for communication with the hypervisor + * and enabling the static_key to use batching. + * + * Return: zero on success or an appropriate error-code. + */ +static int vmballoon_init_batching(struct vmballoon *b) { struct page *page; page = alloc_page(GFP_KERNEL | __GFP_ZERO); if (!page) - return false; + return -ENOMEM; b->batch_page = page_address(page); - return true; + b->batch_max_pages = PAGE_SIZE / sizeof(struct vmballoon_batch_entry); + + static_branch_enable(&vmw_balloon_batching); + + return 0; } /* @@ -932,7 +1197,7 @@ static void vmballoon_doorbell(void *client_data) { struct vmballoon *b = client_data; - STATS_INC(b->stats.doorbell); + vmballoon_stats_gen_inc(b, VMW_BALLOON_STAT_DOORBELL); mod_delayed_work(system_freezable_wq, &b->dwork, 0); } @@ -942,11 +1207,8 @@ static void vmballoon_doorbell(void *client_data) */ static void vmballoon_vmci_cleanup(struct vmballoon *b) { - int error; - - VMWARE_BALLOON_CMD(VMCI_DOORBELL_SET, VMCI_INVALID_ID, - VMCI_INVALID_ID, error); - STATS_INC(b->stats.doorbell_unset); + vmballoon_cmd(b, VMW_BALLOON_CMD_VMCI_DOORBELL_SET, + VMCI_INVALID_ID, VMCI_INVALID_ID); if (!vmci_handle_is_invalid(b->vmci_doorbell)) { vmci_doorbell_destroy(b->vmci_doorbell); @@ -954,12 +1216,19 @@ static void vmballoon_vmci_cleanup(struct vmballoon *b) } } -/* - * Initialize vmci doorbell, to get notified as soon as balloon changes +/** + * vmballoon_vmci_init - Initialize vmci doorbell. + * + * @b: pointer to the balloon. + * + * Return: zero on success or when wakeup command not supported. Error-code + * otherwise. + * + * Initialize vmci doorbell, to get notified as soon as balloon changes. */ 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; @@ -971,10 +1240,9 @@ 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); - - STATS_INC(b->stats.doorbell_set); + error = __vmballoon_cmd(b, VMW_BALLOON_CMD_VMCI_DOORBELL_SET, + b->vmci_doorbell.context, + b->vmci_doorbell.resource, NULL); if (error != VMW_BALLOON_SUCCESS) goto fail; @@ -985,6 +1253,23 @@ fail: return -EIO; } +/** + * vmballoon_pop - Quickly release all pages allocate for the balloon. + * + * @b: pointer to the balloon. + * + * This function is called when host decides to "reset" balloon for one reason + * or another. Unlike normal "deflate" we do not (shall not) notify host of the + * pages being released. + */ +static void vmballoon_pop(struct vmballoon *b) +{ + unsigned long size; + + while ((size = atomic64_read(&b->size))) + vmballoon_deflate(b, size, false); +} + /* * Perform standard reset sequence by popping the balloon (in case it * is not empty) and then restarting protocol. This operation normally @@ -994,18 +1279,18 @@ static void vmballoon_reset(struct vmballoon *b) { int error; + down_write(&b->conf_sem); + vmballoon_vmci_cleanup(b); /* free all pages, skipping monitor unlock */ vmballoon_pop(b); - if (!vmballoon_send_start(b, VMW_BALLOON_CAPABILITIES)) + if (vmballoon_send_start(b, VMW_BALLOON_CAPABILITIES)) return; if ((b->capabilities & VMW_BALLOON_BATCHED_CMDS) != 0) { - b->ops = &vmballoon_batched_ops; - b->batch_max_pages = VMW_BALLOON_BATCH_MAX_PAGES; - if (!vmballoon_init_batching(b)) { + if (vmballoon_init_batching(b)) { /* * We failed to initialize batching, inform the monitor * about it by sending a null capability. @@ -1016,52 +1301,70 @@ static void vmballoon_reset(struct vmballoon *b) return; } } else if ((b->capabilities & VMW_BALLOON_BASIC_CMDS) != 0) { - b->ops = &vmballoon_basic_ops; - b->batch_max_pages = 1; + vmballoon_deinit_batching(b); } + vmballoon_stats_gen_inc(b, VMW_BALLOON_STAT_RESET); b->reset_required = false; error = vmballoon_vmci_init(b); if (error) pr_err("failed to initialize vmci doorbell\n"); - if (!vmballoon_send_guest_id(b)) + if (vmballoon_send_guest_id(b)) pr_err("failed to send guest ID to the host\n"); + + up_write(&b->conf_sem); } -/* - * Balloon work function: reset protocol, if needed, get the new size and - * adjust balloon as needed. Repeat in 1 sec. +/** + * vmballoon_work - periodic balloon worker for reset, inflation and deflation. + * + * @work: pointer to the &work_struct which is provided by the workqueue. + * + * Resets the protocol if needed, gets the new size and adjusts balloon as + * needed. Repeat in 1 sec. */ 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); + int64_t change = 0; if (b->reset_required) vmballoon_reset(b); - if (!b->reset_required && vmballoon_send_get_target(b, &target)) { - /* update target, adjust size */ - b->target = target; + down_read(&b->conf_sem); + + /* + * Update the stats while holding the semaphore to ensure that + * @stats_enabled is consistent with whether the stats are actually + * enabled + */ + vmballoon_stats_gen_inc(b, VMW_BALLOON_STAT_TIMER); + + if (!vmballoon_send_get_target(b)) + change = vmballoon_change(b); + + if (change != 0) { + pr_debug("%s - size: %llu, target %lu\n", __func__, + atomic64_read(&b->size), READ_ONCE(b->target)); - if (b->size < target) + if (change > 0) vmballoon_inflate(b); - else if (target == 0 || - b->size > target + vmballoon_page_size(true)) - vmballoon_deflate(b); + else /* (change < 0) */ + vmballoon_deflate(b, 0, true); } + up_read(&b->conf_sem); + /* * We are using a freezable workqueue so that balloon operations are * stopped while the system transitions to/from sleep/hibernation. */ queue_delayed_work(system_freezable_wq, dwork, round_jiffies_relative(HZ)); + } /* @@ -1069,64 +1372,100 @@ static void vmballoon_work(struct work_struct *work) */ #ifdef CONFIG_DEBUG_FS +static const char * const vmballoon_stat_page_names[] = { + [VMW_BALLOON_PAGE_STAT_ALLOC] = "alloc", + [VMW_BALLOON_PAGE_STAT_ALLOC_FAIL] = "allocFail", + [VMW_BALLOON_PAGE_STAT_REFUSED_ALLOC] = "errAlloc", + [VMW_BALLOON_PAGE_STAT_REFUSED_FREE] = "errFree", + [VMW_BALLOON_PAGE_STAT_FREE] = "free" +}; + +static const char * const vmballoon_stat_names[] = { + [VMW_BALLOON_STAT_TIMER] = "timer", + [VMW_BALLOON_STAT_DOORBELL] = "doorbell", + [VMW_BALLOON_STAT_RESET] = "reset", +}; + +static int vmballoon_enable_stats(struct vmballoon *b) +{ + int r = 0; + + down_write(&b->conf_sem); + + /* did we somehow race with another reader which enabled stats? */ + if (b->stats) + goto out; + + b->stats = kzalloc(sizeof(*b->stats), GFP_KERNEL); + + if (!b->stats) { + /* allocation failed */ + r = -ENOMEM; + goto out; + } + static_key_enable(&balloon_stat_enabled.key); +out: + up_write(&b->conf_sem); + return r; +} + +/** + * vmballoon_debug_show - shows statistics of balloon operations. + * @f: pointer to the &struct seq_file. + * @offset: ignored. + * + * Provides the statistics that can be accessed in vmmemctl in the debugfs. + * To avoid the overhead - mainly that of memory - of collecting the statistics, + * we only collect statistics after the first time the counters are read. + * + * Return: zero on success or an error code. + */ static int vmballoon_debug_show(struct seq_file *f, void *offset) { struct vmballoon *b = f->private; - struct vmballoon_stats *stats = &b->stats; + int i, j; + + /* enables stats if they are disabled */ + if (!b->stats) { + int r = vmballoon_enable_stats(b); + + if (r) + return r; + } /* format capabilities info */ - seq_printf(f, - "balloon capabilities: %#4x\n" - "used capabilities: %#4lx\n" - "is resetting: %c\n", - VMW_BALLOON_CAPABILITIES, b->capabilities, - b->reset_required ? 'y' : 'n'); + seq_printf(f, "%-22s: %#16x\n", "balloon capabilities", + VMW_BALLOON_CAPABILITIES); + seq_printf(f, "%-22s: %#16lx\n", "used capabilities", b->capabilities); + seq_printf(f, "%-22s: %16s\n", "is resetting", + b->reset_required ? "y" : "n"); /* format size info */ - seq_printf(f, - "target: %8d pages\n" - "current: %8d pages\n", - b->target, b->size); - - seq_printf(f, - "\n" - "timer: %8u\n" - "doorbell: %8u\n" - "start: %8u (%4u failed)\n" - "guestType: %8u (%4u failed)\n" - "2m-lock: %8u (%4u failed)\n" - "lock: %8u (%4u failed)\n" - "2m-unlock: %8u (%4u failed)\n" - "unlock: %8u (%4u failed)\n" - "target: %8u (%4u failed)\n" - "prim2mAlloc: %8u (%4u failed)\n" - "primNoSleepAlloc: %8u (%4u failed)\n" - "primCanSleepAlloc: %8u (%4u failed)\n" - "prim2mFree: %8u\n" - "primFree: %8u\n" - "err2mAlloc: %8u\n" - "errAlloc: %8u\n" - "err2mFree: %8u\n" - "errFree: %8u\n" - "doorbellSet: %8u\n" - "doorbellUnset: %8u\n", - stats->timer, - stats->doorbell, - stats->start, stats->start_fail, - stats->guest_type, stats->guest_type_fail, - stats->lock[true], stats->lock_fail[true], - stats->lock[false], stats->lock_fail[false], - stats->unlock[true], stats->unlock_fail[true], - stats->unlock[false], stats->unlock_fail[false], - stats->target, stats->target_fail, - stats->alloc[true], stats->alloc_fail[true], - stats->alloc[false], stats->alloc_fail[false], - stats->sleep_alloc, stats->sleep_alloc_fail, - stats->free[true], - stats->free[false], - stats->refused_alloc[true], stats->refused_alloc[false], - stats->refused_free[true], stats->refused_free[false], - stats->doorbell_set, stats->doorbell_unset); + seq_printf(f, "%-22s: %16lu\n", "target", READ_ONCE(b->target)); + seq_printf(f, "%-22s: %16llu\n", "current", atomic64_read(&b->size)); + + for (i = 0; i < VMW_BALLOON_CMD_NUM; i++) { + if (vmballoon_cmd_names[i] == NULL) + continue; + + seq_printf(f, "%-22s: %16llu (%llu failed)\n", + vmballoon_cmd_names[i], + atomic64_read(&b->stats->ops[i][VMW_BALLOON_OP_STAT]), + atomic64_read(&b->stats->ops[i][VMW_BALLOON_OP_FAIL_STAT])); + } + + for (i = 0; i < VMW_BALLOON_STAT_NUM; i++) + seq_printf(f, "%-22s: %16llu\n", + vmballoon_stat_names[i], + atomic64_read(&b->stats->general_stat[i])); + + for (i = 0; i < VMW_BALLOON_PAGE_STAT_NUM; i++) { + for (j = 0; j < VMW_BALLOON_NUM_PAGE_SIZES; j++) + seq_printf(f, "%-18s(%s): %16llu\n", + vmballoon_stat_page_names[i], + vmballoon_page_size_names[j], + atomic64_read(&b->stats->page_stat[i][j])); + } return 0; } @@ -1161,7 +1500,10 @@ static int __init vmballoon_debugfs_init(struct vmballoon *b) static void __exit vmballoon_debugfs_exit(struct vmballoon *b) { + static_key_disable(&balloon_stat_enabled.key); debugfs_remove(b->dbg_entry); + kfree(b->stats); + b->stats = NULL; } #else @@ -1179,8 +1521,9 @@ static inline void vmballoon_debugfs_exit(struct vmballoon *b) static int __init vmballoon_init(void) { + enum vmballoon_page_size_type page_size; int error; - unsigned is_2m_pages; + /* * Check if we are running on VMware's hypervisor and bail out * if we are not. @@ -1188,11 +1531,10 @@ static int __init vmballoon_init(void) if (x86_hyper_type != X86_HYPER_VMWARE) return -ENODEV; - for (is_2m_pages = 0; is_2m_pages < VMW_BALLOON_NUM_PAGE_SIZES; - is_2m_pages++) { - INIT_LIST_HEAD(&balloon.page_sizes[is_2m_pages].pages); - INIT_LIST_HEAD(&balloon.page_sizes[is_2m_pages].refused_pages); - } + for (page_size = VMW_BALLOON_4K_PAGE; + page_size <= VMW_BALLOON_LAST_SIZE; page_size++) + INIT_LIST_HEAD(&balloon.page_sizes[page_size].pages); + INIT_DELAYED_WORK(&balloon.dwork, vmballoon_work); @@ -1200,6 +1542,8 @@ static int __init vmballoon_init(void) if (error) return error; + spin_lock_init(&balloon.comm_lock); + init_rwsem(&balloon.conf_sem); balloon.vmci_doorbell = VMCI_INVALID_HANDLE; balloon.batch_page = NULL; balloon.page = NULL; |