diff options
Diffstat (limited to 'drivers/gpu/drm/vmwgfx/vmwgfx_msg.c')
| -rw-r--r-- | drivers/gpu/drm/vmwgfx/vmwgfx_msg.c | 579 |
1 files changed, 577 insertions, 2 deletions
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c index 3d08f5700bdb..ed9c7b3a1e08 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c @@ -31,10 +31,12 @@ #include <linux/mem_encrypt.h> #include <asm/hypervisor.h> +#include <drm/drm_ioctl.h> #include "vmwgfx_drv.h" #include "vmwgfx_msg_x86.h" #include "vmwgfx_msg_arm64.h" +#include "vmwgfx_mksstat.h" #define MESSAGE_STATUS_SUCCESS 0x0001 #define MESSAGE_STATUS_DORECV 0x0002 @@ -56,6 +58,11 @@ #define VMW_PORT_CMD_RECVSIZE (MSG_TYPE_RECVSIZE << 16 | VMW_PORT_CMD_MSG) #define VMW_PORT_CMD_RECVSTATUS (MSG_TYPE_RECVSTATUS << 16 | VMW_PORT_CMD_MSG) +#define VMW_PORT_CMD_MKS_GUEST_STATS 85 +#define VMW_PORT_CMD_MKSGS_RESET (0 << 16 | VMW_PORT_CMD_MKS_GUEST_STATS) +#define VMW_PORT_CMD_MKSGS_ADD_PPN (1 << 16 | VMW_PORT_CMD_MKS_GUEST_STATS) +#define VMW_PORT_CMD_MKSGS_REMOVE_PPN (2 << 16 | VMW_PORT_CMD_MKS_GUEST_STATS) + #define HIGH_WORD(X) ((X & 0xFFFF0000) >> 16) #define MAX_USER_MSG_LENGTH PAGE_SIZE @@ -155,6 +162,7 @@ static unsigned long vmw_port_hb_out(struct rpc_channel *channel, /* HB port can't access encrypted memory. */ if (hb && !mem_encrypt_active()) { unsigned long bp = channel->cookie_high; + u32 channel_id = (channel->channel_id << 16); si = (uintptr_t) msg; di = channel->cookie_low; @@ -162,7 +170,7 @@ static unsigned long vmw_port_hb_out(struct rpc_channel *channel, VMW_PORT_HB_OUT( (MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG, msg_len, si, di, - VMWARE_HYPERVISOR_HB | (channel->channel_id << 16) | + VMWARE_HYPERVISOR_HB | channel_id | VMWARE_HYPERVISOR_OUT, VMW_HYPERVISOR_MAGIC, bp, eax, ebx, ecx, edx, si, di); @@ -210,6 +218,7 @@ static unsigned long vmw_port_hb_in(struct rpc_channel *channel, char *reply, /* HB port can't access encrypted memory */ if (hb && !mem_encrypt_active()) { unsigned long bp = channel->cookie_low; + u32 channel_id = (channel->channel_id << 16); si = channel->cookie_high; di = (uintptr_t) reply; @@ -217,7 +226,7 @@ static unsigned long vmw_port_hb_in(struct rpc_channel *channel, char *reply, VMW_PORT_HB_IN( (MESSAGE_STATUS_SUCCESS << 16) | VMW_PORT_CMD_HB_MSG, reply_len, si, di, - VMWARE_HYPERVISOR_HB | (channel->channel_id << 16), + VMWARE_HYPERVISOR_HB | channel_id, VMW_HYPERVISOR_MAGIC, bp, eax, ebx, ecx, edx, si, di); @@ -612,3 +621,569 @@ out_open: return -EINVAL; } + +/** + * reset_ppn_array: Resets a PPN64 array to INVALID_PPN64 content + * + * @arr: Array to reset. + * @size: Array length. + */ +static inline void reset_ppn_array(PPN64 *arr, size_t size) +{ + size_t i; + + BUG_ON(!arr || size == 0); + + for (i = 0; i < size; ++i) + arr[i] = INVALID_PPN64; +} + +/** + * hypervisor_ppn_reset_all: Removes all mksGuestStat instance descriptors from + * the hypervisor. All related pages should be subsequently unpinned or freed. + * + */ +static inline void hypervisor_ppn_reset_all(void) +{ + unsigned long eax, ebx, ecx, edx, si = 0, di = 0; + + VMW_PORT(VMW_PORT_CMD_MKSGS_RESET, + 0, si, di, + 0, + VMW_HYPERVISOR_MAGIC, + eax, ebx, ecx, edx, si, di); +} + +/** + * hypervisor_ppn_add: Adds a single mksGuestStat instance descriptor to the + * hypervisor. Any related userspace pages should be pinned in advance. + * + * @pfn: Physical page number of the instance descriptor + */ +static inline void hypervisor_ppn_add(PPN64 pfn) +{ + unsigned long eax, ebx, ecx, edx, si = 0, di = 0; + + VMW_PORT(VMW_PORT_CMD_MKSGS_ADD_PPN, + (unsigned long)pfn, si, di, + 0, + VMW_HYPERVISOR_MAGIC, + eax, ebx, ecx, edx, si, di); +} + +/** + * hypervisor_ppn_remove: Removes a single mksGuestStat instance descriptor from + * the hypervisor. All related pages should be subsequently unpinned or freed. + * + * @pfn: Physical page number of the instance descriptor + */ +static inline void hypervisor_ppn_remove(PPN64 pfn) +{ + unsigned long eax, ebx, ecx, edx, si = 0, di = 0; + + VMW_PORT(VMW_PORT_CMD_MKSGS_REMOVE_PPN, + (unsigned long)pfn, si, di, + 0, + VMW_HYPERVISOR_MAGIC, + eax, ebx, ecx, edx, si, di); +} + +#if IS_ENABLED(CONFIG_DRM_VMWGFX_MKSSTATS) + +/* Order of the total number of pages used for kernel-internal mksGuestStat; at least 2 */ +#define MKSSTAT_KERNEL_PAGES_ORDER 2 +/* Header to the text description of mksGuestStat instance descriptor */ +#define MKSSTAT_KERNEL_DESCRIPTION "vmwgfx" + +/* Kernel mksGuestStats counter names and desciptions; same order as enum mksstat_kern_stats_t */ +static const char* const mksstat_kern_name_desc[MKSSTAT_KERN_COUNT][2] = +{ + { "vmw_execbuf_ioctl", "vmw_execbuf_ioctl" }, +}; + +/** + * mksstat_init_record: Initializes an MKSGuestStatCounter-based record + * for the respective mksGuestStat index. + * + * @stat_idx: Index of the MKSGuestStatCounter-based mksGuestStat record. + * @pstat: Pointer to array of MKSGuestStatCounterTime. + * @pinfo: Pointer to array of MKSGuestStatInfoEntry. + * @pstrs: Pointer to current end of the name/description sequence. + * Return: Pointer to the new end of the names/description sequence. + */ + +static inline char *mksstat_init_record(mksstat_kern_stats_t stat_idx, + MKSGuestStatCounterTime *pstat, MKSGuestStatInfoEntry *pinfo, char *pstrs) +{ + char *const pstrd = pstrs + strlen(mksstat_kern_name_desc[stat_idx][0]) + 1; + strcpy(pstrs, mksstat_kern_name_desc[stat_idx][0]); + strcpy(pstrd, mksstat_kern_name_desc[stat_idx][1]); + + pinfo[stat_idx].name.s = pstrs; + pinfo[stat_idx].description.s = pstrd; + pinfo[stat_idx].flags = MKS_GUEST_STAT_FLAG_NONE; + pinfo[stat_idx].stat.counter = (MKSGuestStatCounter *)&pstat[stat_idx]; + + return pstrd + strlen(mksstat_kern_name_desc[stat_idx][1]) + 1; +} + +/** + * mksstat_init_record_time: Initializes an MKSGuestStatCounterTime-based record + * for the respective mksGuestStat index. + * + * @stat_idx: Index of the MKSGuestStatCounterTime-based mksGuestStat record. + * @pstat: Pointer to array of MKSGuestStatCounterTime. + * @pinfo: Pointer to array of MKSGuestStatInfoEntry. + * @pstrs: Pointer to current end of the name/description sequence. + * Return: Pointer to the new end of the names/description sequence. + */ + +static inline char *mksstat_init_record_time(mksstat_kern_stats_t stat_idx, + MKSGuestStatCounterTime *pstat, MKSGuestStatInfoEntry *pinfo, char *pstrs) +{ + char *const pstrd = pstrs + strlen(mksstat_kern_name_desc[stat_idx][0]) + 1; + strcpy(pstrs, mksstat_kern_name_desc[stat_idx][0]); + strcpy(pstrd, mksstat_kern_name_desc[stat_idx][1]); + + pinfo[stat_idx].name.s = pstrs; + pinfo[stat_idx].description.s = pstrd; + pinfo[stat_idx].flags = MKS_GUEST_STAT_FLAG_TIME; + pinfo[stat_idx].stat.counterTime = &pstat[stat_idx]; + + return pstrd + strlen(mksstat_kern_name_desc[stat_idx][1]) + 1; +} + +/** + * mksstat_init_kern_id: Creates a single mksGuestStat instance descriptor and + * kernel-internal counters. Adds PFN mapping to the hypervisor. + * + * Create a single mksGuestStat instance descriptor and corresponding structures + * for all kernel-internal counters. The corresponding PFNs are mapped with the + * hypervisor. + * + * @ppage: Output pointer to page containing the instance descriptor. + * Return: Zero on success, negative error code on error. + */ + +static int mksstat_init_kern_id(struct page **ppage) +{ + MKSGuestStatInstanceDescriptor *pdesc; + MKSGuestStatCounterTime *pstat; + MKSGuestStatInfoEntry *pinfo; + char *pstrs, *pstrs_acc; + + /* Allocate pages for the kernel-internal instance descriptor */ + struct page *page = alloc_pages(GFP_KERNEL | __GFP_ZERO, MKSSTAT_KERNEL_PAGES_ORDER); + + if (!page) + return -ENOMEM; + + pdesc = page_address(page); + pstat = vmw_mksstat_get_kern_pstat(pdesc); + pinfo = vmw_mksstat_get_kern_pinfo(pdesc); + pstrs = vmw_mksstat_get_kern_pstrs(pdesc); + + /* Set up all kernel-internal counters and corresponding structures */ + pstrs_acc = pstrs; + pstrs_acc = mksstat_init_record_time(MKSSTAT_KERN_EXECBUF, pstat, pinfo, pstrs_acc); + + /* Add new counters above, in their order of appearance in mksstat_kern_stats_t */ + + BUG_ON(pstrs_acc - pstrs > PAGE_SIZE); + + /* Set up the kernel-internal instance descriptor */ + pdesc->reservedMBZ = 0; + pdesc->statStartVA = (uintptr_t)pstat; + pdesc->strsStartVA = (uintptr_t)pstrs; + pdesc->statLength = sizeof(*pstat) * MKSSTAT_KERN_COUNT; + pdesc->infoLength = sizeof(*pinfo) * MKSSTAT_KERN_COUNT; + pdesc->strsLength = pstrs_acc - pstrs; + snprintf(pdesc->description, ARRAY_SIZE(pdesc->description) - 1, "%s pid=%d", + MKSSTAT_KERNEL_DESCRIPTION, current->pid); + + pdesc->statPPNs[0] = page_to_pfn(virt_to_page(pstat)); + reset_ppn_array(pdesc->statPPNs + 1, ARRAY_SIZE(pdesc->statPPNs) - 1); + + pdesc->infoPPNs[0] = page_to_pfn(virt_to_page(pinfo)); + reset_ppn_array(pdesc->infoPPNs + 1, ARRAY_SIZE(pdesc->infoPPNs) - 1); + + pdesc->strsPPNs[0] = page_to_pfn(virt_to_page(pstrs)); + reset_ppn_array(pdesc->strsPPNs + 1, ARRAY_SIZE(pdesc->strsPPNs) - 1); + + *ppage = page; + + hypervisor_ppn_add((PPN64)page_to_pfn(page)); + + return 0; +} + +/** + * vmw_mksstat_get_kern_slot: Acquires a slot for a single kernel-internal + * mksGuestStat instance descriptor. + * + * Find a slot for a single kernel-internal mksGuestStat instance descriptor. + * In case no such was already present, allocate a new one and set up a kernel- + * internal mksGuestStat instance descriptor for the former. + * + * @pid: Process for which a slot is sought. + * @dev_priv: Identifies the drm private device. + * Return: Non-negative slot on success, negative error code on error. + */ + +int vmw_mksstat_get_kern_slot(pid_t pid, struct vmw_private *dev_priv) +{ + const size_t base = (u32)hash_32(pid, MKSSTAT_CAPACITY_LOG2); + size_t i; + + for (i = 0; i < ARRAY_SIZE(dev_priv->mksstat_kern_pids); ++i) { + const size_t slot = (i + base) % ARRAY_SIZE(dev_priv->mksstat_kern_pids); + + /* Check if an instance descriptor for this pid is already present */ + if (pid == (pid_t)atomic_read(&dev_priv->mksstat_kern_pids[slot])) + return (int)slot; + + /* Set up a new instance descriptor for this pid */ + if (!atomic_cmpxchg(&dev_priv->mksstat_kern_pids[slot], 0, MKSSTAT_PID_RESERVED)) { + const int ret = mksstat_init_kern_id(&dev_priv->mksstat_kern_pages[slot]); + + if (!ret) { + /* Reset top-timer tracking for this slot */ + dev_priv->mksstat_kern_top_timer[slot] = MKSSTAT_KERN_COUNT; + + atomic_set(&dev_priv->mksstat_kern_pids[slot], pid); + return (int)slot; + } + + atomic_set(&dev_priv->mksstat_kern_pids[slot], 0); + return ret; + } + } + + return -ENOSPC; +} + +#endif + +/** + * vmw_mksstat_cleanup_descriptor: Frees a single userspace-originating + * mksGuestStat instance-descriptor page and unpins all related user pages. + * + * Unpin all user pages realated to this instance descriptor and free + * the instance-descriptor page itself. + * + * @page: Page of the instance descriptor. + */ + +static void vmw_mksstat_cleanup_descriptor(struct page *page) +{ + MKSGuestStatInstanceDescriptor *pdesc = page_address(page); + size_t i; + + for (i = 0; i < ARRAY_SIZE(pdesc->statPPNs) && pdesc->statPPNs[i] != INVALID_PPN64; ++i) + unpin_user_page(pfn_to_page(pdesc->statPPNs[i])); + + for (i = 0; i < ARRAY_SIZE(pdesc->infoPPNs) && pdesc->infoPPNs[i] != INVALID_PPN64; ++i) + unpin_user_page(pfn_to_page(pdesc->infoPPNs[i])); + + for (i = 0; i < ARRAY_SIZE(pdesc->strsPPNs) && pdesc->strsPPNs[i] != INVALID_PPN64; ++i) + unpin_user_page(pfn_to_page(pdesc->strsPPNs[i])); + + __free_page(page); +} + +/** + * vmw_mksstat_remove_all: Resets all mksGuestStat instance descriptors + * from the hypervisor. + * + * Discard all hypervisor PFN mappings, containing active mksGuestState instance + * descriptors, unpin the related userspace pages and free the related kernel pages. + * + * @dev_priv: Identifies the drm private device. + * Return: Zero on success, negative error code on error. + */ + +int vmw_mksstat_remove_all(struct vmw_private *dev_priv) +{ + int ret = 0; + size_t i; + + /* Discard all PFN mappings with the hypervisor */ + hypervisor_ppn_reset_all(); + + /* Discard all userspace-originating instance descriptors and unpin all related pages */ + for (i = 0; i < ARRAY_SIZE(dev_priv->mksstat_user_pids); ++i) { + const pid_t pid0 = (pid_t)atomic_read(&dev_priv->mksstat_user_pids[i]); + + if (!pid0) + continue; + + if (pid0 != MKSSTAT_PID_RESERVED) { + const pid_t pid1 = atomic_cmpxchg(&dev_priv->mksstat_user_pids[i], pid0, MKSSTAT_PID_RESERVED); + + if (!pid1) + continue; + + if (pid1 == pid0) { + struct page *const page = dev_priv->mksstat_user_pages[i]; + + BUG_ON(!page); + + dev_priv->mksstat_user_pages[i] = NULL; + atomic_set(&dev_priv->mksstat_user_pids[i], 0); + + vmw_mksstat_cleanup_descriptor(page); + continue; + } + } + + ret = -EAGAIN; + } + +#if IS_ENABLED(CONFIG_DRM_VMWGFX_MKSSTATS) + /* Discard all kernel-internal instance descriptors and free all related pages */ + for (i = 0; i < ARRAY_SIZE(dev_priv->mksstat_kern_pids); ++i) { + const pid_t pid0 = (pid_t)atomic_read(&dev_priv->mksstat_kern_pids[i]); + + if (!pid0) + continue; + + if (pid0 != MKSSTAT_PID_RESERVED) { + const pid_t pid1 = atomic_cmpxchg(&dev_priv->mksstat_kern_pids[i], pid0, MKSSTAT_PID_RESERVED); + + if (!pid1) + continue; + + if (pid1 == pid0) { + struct page *const page = dev_priv->mksstat_kern_pages[i]; + + BUG_ON(!page); + + dev_priv->mksstat_kern_pages[i] = NULL; + atomic_set(&dev_priv->mksstat_kern_pids[i], 0); + + __free_pages(page, MKSSTAT_KERNEL_PAGES_ORDER); + continue; + } + } + + ret = -EAGAIN; + } + +#endif + return ret; +} + +/** + * vmw_mksstat_reset_ioctl: Resets all mksGuestStat instance descriptors + * from the hypervisor. + * + * Discard all hypervisor PFN mappings, containing active mksGuestStat instance + * descriptors, unpin the related userspace pages and free the related kernel pages. + * + * @dev: Identifies the drm device. + * @data: Pointer to the ioctl argument. + * @file_priv: Identifies the caller; unused. + * Return: Zero on success, negative error code on error. + */ + +int vmw_mksstat_reset_ioctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + struct vmw_private *const dev_priv = vmw_priv(dev); + return vmw_mksstat_remove_all(dev_priv); +} + +/** + * vmw_mksstat_add_ioctl: Creates a single userspace-originating mksGuestStat + * instance descriptor and registers that with the hypervisor. + * + * Create a hypervisor PFN mapping, containing a single mksGuestStat instance + * descriptor and pin the corresponding userspace pages. + * + * @dev: Identifies the drm device. + * @data: Pointer to the ioctl argument. + * @file_priv: Identifies the caller; unused. + * Return: Zero on success, negative error code on error. + */ + +int vmw_mksstat_add_ioctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + struct drm_vmw_mksstat_add_arg *arg = + (struct drm_vmw_mksstat_add_arg *) data; + + struct vmw_private *const dev_priv = vmw_priv(dev); + + struct page *page; + MKSGuestStatInstanceDescriptor *pdesc; + const size_t num_pages_stat = vmw_num_pages(arg->stat_len); + const size_t num_pages_info = vmw_num_pages(arg->info_len); + const size_t num_pages_strs = vmw_num_pages(arg->strs_len); + long desc_len; + long nr_pinned_stat; + long nr_pinned_info; + long nr_pinned_strs; + struct page *pages_stat[ARRAY_SIZE(pdesc->statPPNs)]; + struct page *pages_info[ARRAY_SIZE(pdesc->infoPPNs)]; + struct page *pages_strs[ARRAY_SIZE(pdesc->strsPPNs)]; + size_t i, slot; + + arg->id = -1; + + if (!arg->stat || !arg->info || !arg->strs) + return -EINVAL; + + if (!arg->stat_len || !arg->info_len || !arg->strs_len) + return -EINVAL; + + if (!arg->description) + return -EINVAL; + + if (num_pages_stat > ARRAY_SIZE(pdesc->statPPNs) || + num_pages_info > ARRAY_SIZE(pdesc->infoPPNs) || + num_pages_strs > ARRAY_SIZE(pdesc->strsPPNs)) + return -EINVAL; + + /* Find an available slot in the mksGuestStats user array and reserve it */ + for (slot = 0; slot < ARRAY_SIZE(dev_priv->mksstat_user_pids); ++slot) + if (!atomic_cmpxchg(&dev_priv->mksstat_user_pids[slot], 0, MKSSTAT_PID_RESERVED)) + break; + + if (slot == ARRAY_SIZE(dev_priv->mksstat_user_pids)) + return -ENOSPC; + + BUG_ON(dev_priv->mksstat_user_pages[slot]); + + /* Allocate a page for the instance descriptor */ + page = alloc_page(GFP_KERNEL | __GFP_ZERO); + + if (!page) { + atomic_set(&dev_priv->mksstat_user_pids[slot], 0); + return -ENOMEM; + } + + /* Set up the instance descriptor */ + pdesc = page_address(page); + + pdesc->reservedMBZ = 0; + pdesc->statStartVA = arg->stat; + pdesc->strsStartVA = arg->strs; + pdesc->statLength = arg->stat_len; + pdesc->infoLength = arg->info_len; + pdesc->strsLength = arg->strs_len; + desc_len = strncpy_from_user(pdesc->description, u64_to_user_ptr(arg->description), + ARRAY_SIZE(pdesc->description) - 1); + + if (desc_len < 0) { + atomic_set(&dev_priv->mksstat_user_pids[slot], 0); + return -EFAULT; + } + + reset_ppn_array(pdesc->statPPNs, ARRAY_SIZE(pdesc->statPPNs)); + reset_ppn_array(pdesc->infoPPNs, ARRAY_SIZE(pdesc->infoPPNs)); + reset_ppn_array(pdesc->strsPPNs, ARRAY_SIZE(pdesc->strsPPNs)); + + /* Pin mksGuestStat user pages and store those in the instance descriptor */ + nr_pinned_stat = pin_user_pages(arg->stat, num_pages_stat, FOLL_LONGTERM, pages_stat, NULL); + if (num_pages_stat != nr_pinned_stat) + goto err_pin_stat; + + for (i = 0; i < num_pages_stat; ++i) + pdesc->statPPNs[i] = page_to_pfn(pages_stat[i]); + + nr_pinned_info = pin_user_pages(arg->info, num_pages_info, FOLL_LONGTERM, pages_info, NULL); + if (num_pages_info != nr_pinned_info) + goto err_pin_info; + + for (i = 0; i < num_pages_info; ++i) + pdesc->infoPPNs[i] = page_to_pfn(pages_info[i]); + + nr_pinned_strs = pin_user_pages(arg->strs, num_pages_strs, FOLL_LONGTERM, pages_strs, NULL); + if (num_pages_strs != nr_pinned_strs) + goto err_pin_strs; + + for (i = 0; i < num_pages_strs; ++i) + pdesc->strsPPNs[i] = page_to_pfn(pages_strs[i]); + + /* Send the descriptor to the host via a hypervisor call. The mksGuestStat + pages will remain in use until the user requests a matching remove stats + or a stats reset occurs. */ + hypervisor_ppn_add((PPN64)page_to_pfn(page)); + + dev_priv->mksstat_user_pages[slot] = page; + atomic_set(&dev_priv->mksstat_user_pids[slot], task_pgrp_vnr(current)); + + arg->id = slot; + + DRM_DEV_INFO(dev->dev, "pid=%d arg.description='%.*s' id=%zu\n", current->pid, (int)desc_len, pdesc->description, slot); + + return 0; + +err_pin_strs: + if (nr_pinned_strs > 0) + unpin_user_pages(pages_strs, nr_pinned_strs); + +err_pin_info: + if (nr_pinned_info > 0) + unpin_user_pages(pages_info, nr_pinned_info); + +err_pin_stat: + if (nr_pinned_stat > 0) + unpin_user_pages(pages_stat, nr_pinned_stat); + + atomic_set(&dev_priv->mksstat_user_pids[slot], 0); + __free_page(page); + return -ENOMEM; +} + +/** + * vmw_mksstat_remove_ioctl: Removes a single userspace-originating mksGuestStat + * instance descriptor from the hypervisor. + * + * Discard a hypervisor PFN mapping, containing a single mksGuestStat instance + * descriptor and unpin the corresponding userspace pages. + * + * @dev: Identifies the drm device. + * @data: Pointer to the ioctl argument. + * @file_priv: Identifies the caller; unused. + * Return: Zero on success, negative error code on error. + */ + +int vmw_mksstat_remove_ioctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + struct drm_vmw_mksstat_remove_arg *arg = + (struct drm_vmw_mksstat_remove_arg *) data; + + struct vmw_private *const dev_priv = vmw_priv(dev); + + const size_t slot = arg->id; + pid_t pgid, pid; + + if (slot >= ARRAY_SIZE(dev_priv->mksstat_user_pids)) + return -EINVAL; + + DRM_DEV_INFO(dev->dev, "pid=%d arg.id=%zu\n", current->pid, slot); + + pgid = task_pgrp_vnr(current); + pid = atomic_cmpxchg(&dev_priv->mksstat_user_pids[slot], pgid, MKSSTAT_PID_RESERVED); + + if (!pid) + return 0; + + if (pid == pgid) { + struct page *const page = dev_priv->mksstat_user_pages[slot]; + + BUG_ON(!page); + + dev_priv->mksstat_user_pages[slot] = NULL; + atomic_set(&dev_priv->mksstat_user_pids[slot], 0); + + hypervisor_ppn_remove((PPN64)page_to_pfn(page)); + + vmw_mksstat_cleanup_descriptor(page); + return 0; + } + + return -EAGAIN; +} |