vmmon: use build time version check in MapCrossPage()

Previous commit breaks build against kernels older than 5.3 as there used
to be one more argument of handler called by apply_to_page_range(). Use
preprocessor version check so that code intended for kernel 5.8 and later
is not compiled at all when building against older kernels. Also compile
crosspage_set_exec() conditionally to avoid compiler warning.

vmmon-only/include/x86msr.h

@@ -638,7 +638,9 @@ MSRQuery;
 #define MSR_HYPERV_GUESTOSID_OS_WINNT_DERIVATIVE 4ULL
 
 /* MSR for forcing RTM abort to recover PMC3 (see PR 2333817) */
+#ifndef MSR_TSX_FORCE_ABORT
 #define MSR_TSX_FORCE_ABORT                      0x0000010f
+#endif
 #define MSR_TSX_FORCE_ABORT_RTM_BIT_INDEX        0
 
 /*

vmmon-only/linux/hostif.c

@@ -47,13 +47,16 @@
 #include <asm/asm.h>
 #include <asm/io.h>
 #include <asm/page.h>
+#include <asm/tlbflush.h>
 #include <asm/uaccess.h>
+#include <asm/irq_vectors.h>
 #include <linux/capability.h>
 #include <linux/kthread.h>
 #include <linux/wait.h>
 #include <linux/hrtimer.h>
 #include <linux/signal.h>
 #include <linux/taskstats_kern.h> // For linux/sched/signal.h without version check
+#include <linux/eventfd.h>
 
 #include "vmware.h"
 #include "x86apic.h"
@@ -615,6 +618,15 @@ HostIF_FastClockUnlock(int callerID) // IN
    MutexUnlock(&fastClockMutex, callerID);
 }
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0)
+static int crosspage_set_exec(pte_t *pte, unsigned long addr, void *data)
+{
+	struct page *p = data;
+
+	set_pte(pte, mk_pte(p, VM_PAGE_KERNEL_EXEC));
+	return 0;
+}
+#endif
 
 /*
  *----------------------------------------------------------------------
@@ -635,7 +647,29 @@ HostIF_FastClockUnlock(int callerID) // IN
 static void *
 MapCrossPage(struct page *p)  // IN:
 {
+#if COMPAT_LINUX_VERSION_CHECK_LT(5, 8, 0)
    return vmap(&p, 1, VM_MAP, VM_PAGE_KERNEL_EXEC);
+#else
+   void *addr;
+
+   addr = vmap(&p, 1, VM_MAP, VM_PAGE_KERNEL_EXEC);
+   if (!addr)
+	   return NULL;
+
+   /* Starting with 5.8, vmap() always sets the NX bit, but the cross
+    * page needs to be executable. */
+   if (apply_to_page_range(current->mm, (unsigned long)addr, PAGE_SIZE,
+			   crosspage_set_exec, p)) {
+      vunmap(addr);
+      return NULL;
+   }
+
+   preempt_disable();
+   __flush_tlb_all();
+   preempt_enable();
+
+   return addr;
+#endif
 }
 
 
@@ -1739,8 +1773,11 @@ HostIF_EstimateLockedPageLimit(const VMDriver* vm,                // IN
 #else
    lockedPages += global_page_state(NR_PAGETABLE);
 #endif
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
+   /* NR_SLAB_* converted to byte counters in 5.9 */
+   lockedPages += global_node_page_state_pages(NR_SLAB_UNRECLAIMABLE_B);
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 13, 0)
    /* NR_SLAB_* moved from zone to node in 4.13. */
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 13, 0)
    lockedPages += global_node_page_state(NR_SLAB_UNRECLAIMABLE);
 #else
    lockedPages += global_page_state(NR_SLAB_UNRECLAIMABLE);
@@ -2371,6 +2408,27 @@ HostIF_VMLockIsHeld(VMDriver *vm) // IN
 
 #if defined(CONFIG_SMP) || defined(CONFIG_X86_UP_IOAPIC) || \
     defined(CONFIG_X86_UP_APIC) || defined(CONFIG_X86_LOCAL_APIC)
+
+#if COMPAT_LINUX_VERSION_CHECK_LT(5, 8, 0)
+static long compat_copy_from_kernel_nofault(void *dst, VA src, size_t size)
+{
+   mm_segment_t old_fs;
+   long ret;
+
+   old_fs = get_fs();
+   set_fs(KERNEL_DS);
+   ret = HostIF_CopyFromUser(dst, src, size);
+   set_fs(old_fs);
+
+   return ret;
+}
+#else
+static long compat_copy_from_kernel_nofault(void *dst, VA src, size_t size)
+{
+   return copy_from_kernel_nofault(dst, (const void *)src, size);
+}
+#endif
+
 /*
  *----------------------------------------------------------------------
  *
@@ -2390,15 +2448,11 @@ HostIF_VMLockIsHeld(VMDriver *vm) // IN
 static Bool
 isVAReadable(VA r)  // IN:
 {
-   mm_segment_t old_fs;
    uint32 dummy;
-   int ret;
+   long ret;
 
-   old_fs = get_fs();
-   set_fs(KERNEL_DS);
    r = APICR_TO_ADDR(r, APICR_VERSION);
-   ret = HostIF_CopyFromUser(&dummy, r, sizeof dummy);
-   set_fs(old_fs);
+   ret = compat_copy_from_kernel_nofault(&dummy, r, sizeof(dummy));
 
    return ret == 0;
 }
@@ -2554,11 +2608,12 @@ HostIF_SemaphoreWait(VMDriver *vm,   // IN:
                      uint64 *args)   // IN:
 {
    struct file *file;
-   mm_segment_t old_fs;
    int res;
    int waitFD = args[0];
    int timeoutms = args[2];
    uint64 value;
+   struct poll_wqueues table;
+   unsigned int mask;
 
    ASSERT(vcpuid < vm->numVCPUs);
 
@@ -2567,33 +2622,29 @@ HostIF_SemaphoreWait(VMDriver *vm,   // IN:
       return MX_WAITERROR;
    }
 
-   old_fs = get_fs();
-   set_fs(KERNEL_DS);
-
-   {
-      struct poll_wqueues table;
-      unsigned int mask;
-
-      poll_initwait(&table);
-      current->state = TASK_INTERRUPTIBLE;
-      mask = compat_vfs_poll(file, &table.pt);
-      if (!(mask & (POLLIN | POLLERR | POLLHUP))) {
-         vm->vmhost->vcpuSemaTask[vcpuid] = current;
-         schedule_timeout(timeoutms * HZ / 1000);  // convert to Hz
-         vm->vmhost->vcpuSemaTask[vcpuid] = NULL;
-      }
-      current->state = TASK_RUNNING;
-      poll_freewait(&table);
+   poll_initwait(&table);
+   current->state = TASK_INTERRUPTIBLE;
+   mask = compat_vfs_poll(file, &table.pt);
+   if (!(mask & (POLLIN | POLLERR | POLLHUP))) {
+      vm->vmhost->vcpuSemaTask[vcpuid] = current;
+      schedule_timeout(timeoutms * HZ / 1000);  // convert to Hz
+      vm->vmhost->vcpuSemaTask[vcpuid] = NULL;
    }
+   current->state = TASK_RUNNING;
+   poll_freewait(&table);
 
    /*
     * Userland only writes in multiples of sizeof(uint64). This will allow
     * the code to happily deal with a pipe or an eventfd. We only care about
     * reading no bytes (EAGAIN - non blocking fd) or sizeof(uint64).
+    *
+    * Upstream Linux changed the function parameter types/ordering in 4.14.0.
     */
-
-   res = file->f_op->read(file, (char *) &value, sizeof value, &file->f_pos);
-
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 14, 0)
+   res = kernel_read(file, file->f_pos, (char *)&value, sizeof value);
+#else
+   res = kernel_read(file, &value, sizeof value, &file->f_pos);
+#endif
    if (res == sizeof value) {
       res = MX_WAITNORMAL;
    } else {
@@ -2602,7 +2653,6 @@ HostIF_SemaphoreWait(VMDriver *vm,   // IN:
       }
    }
 
-   set_fs(old_fs);
    fput(file);
 
    /*
@@ -2689,8 +2739,8 @@ HostIF_SemaphoreForceWakeup(VMDriver *vm,       // IN:
 int
 HostIF_SemaphoreSignal(uint64 *args)  // IN:
 {
+   struct eventfd_ctx *eventfd;
    struct file *file;
-   mm_segment_t old_fs;
    int res;
    int signalFD = args[1];
    uint64 value = 1;  // make an eventfd happy should it be there
@@ -2700,22 +2750,34 @@ HostIF_SemaphoreSignal(uint64 *args)  // IN:
       return MX_WAITERROR;
    }
 
-   old_fs = get_fs();
-   set_fs(KERNEL_DS);
+   /*
+    * If it's eventfd, use specific eventfd interface as kernel writes
+    * to eventfd may not be allowed in kernel 5.10 and later.
+    */
+   eventfd = eventfd_ctx_fileget(file);
+   if (!IS_ERR(eventfd)) {
+      eventfd_signal(eventfd, 1);
+      fput(file);
+      return MX_WAITNORMAL;
+   }
 
    /*
     * Always write sizeof(uint64) bytes. This works fine for eventfd and
     * pipes. The data written is formatted to make an eventfd happy should
     * it be present.
+    *
+    * Upstream Linux changed the function parameter types/ordering in 4.14.0.
     */
-
-   res = file->f_op->write(file, (char *) &value, sizeof value, &file->f_pos);
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 14, 0)
+   res = kernel_write(file, (char *)&value, sizeof value, file->f_pos);
+#else
+   res = kernel_write(file, &value, sizeof value, &file->f_pos);
+#endif
 
    if (res == sizeof value) {
       res = MX_WAITNORMAL;
    }
 
-   set_fs(old_fs);
    fput(file);
 
    /*
@@ -3262,12 +3324,9 @@ static int
 HostIFFastClockThread(void *unused)  // IN:
 {
    int res;
-   mm_segment_t oldFS;
    unsigned int rate = 0;
    unsigned int prevRate = 0;
 
-   oldFS = get_fs();
-   set_fs(KERNEL_DS);
    allow_signal(SIGKILL);
 
    while ((rate = linuxState.fastClockRate) > MIN_RATE) {
@@ -3290,8 +3349,6 @@ HostIFFastClockThread(void *unused)  // IN:
    }
 
  out:
-   set_fs(oldFS);
-
    /*
     * Do not exit thread until we are told to do so.
     */

vmnet-only/bridge.c

@@ -66,7 +66,7 @@
 #endif
 
 #if LOGLEVEL >= 4
-static struct timeval vnetTime;
+static u64 vnetTime;
 #endif
 
 typedef struct VNetBridge VNetBridge;
@@ -693,7 +693,7 @@ VNetBridgeReceiveFromVNet(VNetJack        *this, // IN: jack
 
 	 netif_rx_ni(clone);
 #	 if LOGLEVEL >= 4
-	 do_gettimeofday(&vnetTime);
+	 vnetTime = ktime_get_ns();
 #	 endif
       }
    }
@@ -1490,12 +1490,11 @@ VNetBridgeReceiveFromDev(struct sk_buff *skb,         // IN: packet to receive
 
 #  if LOGLEVEL >= 4
    {
-      struct timeval now;
-      do_gettimeofday(&now);
+      u64 now;
+
+      now = ktime_get_ns();
       LOG(3, (KERN_DEBUG "bridge-%s: time %d\n",
-	      bridge->name,
-	      (int)((now.tv_sec * 1000000 + now.tv_usec)
-                    - (vnetTime.tv_sec * 1000000 + vnetTime.tv_usec))));
+	      bridge->name, (int)((now - vnetTime) / NSEC_PER_USEC)));
    }
 #  endif
 

vmnet-only/userif.c

@@ -81,10 +81,30 @@ extern unsigned int  vnet_max_qlen;
 #   define skb_frag_page(frag) (frag)->page
 #   define skb_frag_size(frag) (frag)->size
 #endif
-#if COMPAT_LINUX_VERSION_CHECK_LT(5, 4, 0)
+#if COMPAT_LINUX_VERSION_CHECK_LT(5, 4, 0) && \
+    !(defined(CONFIG_SUSE_VERSION) && CONFIG_SUSE_VERSION == 15 && \
+      defined(CONFIG_SUSE_PATCHLEVEL) && CONFIG_SUSE_PATCHLEVEL >= 2)
 #   define skb_frag_off(frag) (frag)->page_offset
 #endif
 
+#if COMPAT_LINUX_VERSION_CHECK_LT(5, 10, 0)
+static inline
+__wsum compat_csum_and_copy_to_user(const void *src, void __user *dst, int len)
+{
+	int err;
+	__wsum ret;
+
+	ret = csum_and_copy_to_user(src, dst, len, 0, &err);
+	return err ? 0 : ret;
+}
+#else
+static inline
+__wsum compat_csum_and_copy_to_user(const void *src, void __user *dst, int len)
+{
+	return csum_and_copy_to_user(src, dst, len);
+}
+#endif
+
 /*
  *-----------------------------------------------------------------------------
  *
@@ -546,7 +566,6 @@ VNetCsumCopyDatagram(const struct sk_buff *skb,	// IN: skb to copy
 		     char *buf)			// OUT: where to copy data
 {
    unsigned int csum;
-   int err = 0;
    int len = skb_headlen(skb) - offset;
    char *curr = buf;
    const skb_frag_t *frag;
@@ -559,10 +578,9 @@ VNetCsumCopyDatagram(const struct sk_buff *skb,	// IN: skb to copy
       return -EINVAL;
    }
 
-   csum = csum_and_copy_to_user(skb->data + offset, curr, len, 0, &err);
-   if (err) {
-      return err;
-   }
+   csum = compat_csum_and_copy_to_user(skb->data + offset, curr, len);
+   if (!csum)
+	   return -EFAULT;
    curr += len;
 
    for (frag = skb_shinfo(skb)->frags;
@@ -573,13 +591,12 @@ VNetCsumCopyDatagram(const struct sk_buff *skb,	// IN: skb to copy
 	 const void *vaddr;
 
 	 vaddr = kmap(skb_frag_page(frag));
-	 tmpCsum = csum_and_copy_to_user(vaddr + skb_frag_off(frag),
-					 curr, skb_frag_size(frag), 0, &err);
+	 tmpCsum = compat_csum_and_copy_to_user(vaddr + skb_frag_off(frag),
+						curr, skb_frag_size(frag));
 	 kunmap(skb_frag_page(frag));
 
-	 if (err) {
-	    return err;
-	 }
+	 if (!tmpCsum)
+		 return -EFAULT;
 	 csum = csum_block_add(csum, tmpCsum, curr - buf);
 	 curr += skb_frag_size(frag);
       }