drivers:hv: Move MMIO range picking from hyper_fb to hv_vmbus
authorJake Oshins <jakeo@microsoft.com>
Wed, 5 Aug 2015 07:52:37 +0000 (00:52 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 5 Aug 2015 18:41:31 +0000 (11:41 -0700)
This patch deletes the logic from hyperv_fb which picked a range of MMIO space
for the frame buffer and adds new logic to hv_vmbus which picks ranges for
child drivers.  The new logic isn't quite the same as the old, as it considers
more possible ranges.

Signed-off-by: Jake Oshins <jakeo@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/hv/vmbus_drv.c
drivers/video/fbdev/hyperv_fb.c
include/linux/hyperv.h

index ee59e06c21943e7fc9691911778c43d747dac1cc..8c3eaee8c54c7f32f780decd627bc5ae34ad89e6 100644 (file)
@@ -39,6 +39,7 @@
 #include <asm/mshyperv.h>
 #include <linux/notifier.h>
 #include <linux/ptrace.h>
+#include <linux/screen_info.h>
 #include <linux/kdebug.h>
 #include "hyperv_vmbus.h"
 
@@ -103,7 +104,6 @@ static struct notifier_block hyperv_panic_block = {
 };
 
 struct resource *hyperv_mmio;
-EXPORT_SYMBOL_GPL(hyperv_mmio);
 
 static int vmbus_exists(void)
 {
@@ -891,8 +891,8 @@ err_cleanup:
 }
 
 /**
- * __vmbus_child_driver_register - Register a vmbus's driver
- * @drv: Pointer to driver structure you want to register
+ * __vmbus_child_driver_register() - Register a vmbus's driver
+ * @hv_driver: Pointer to driver structure you want to register
  * @owner: owner module of the drv
  * @mod_name: module name string
  *
@@ -924,7 +924,8 @@ EXPORT_SYMBOL_GPL(__vmbus_driver_register);
 
 /**
  * vmbus_driver_unregister() - Unregister a vmbus's driver
- * @drv: Pointer to driver structure you want to un-register
+ * @hv_driver: Pointer to driver structure you want to
+ *             un-register
  *
  * Un-register the given driver that was previous registered with a call to
  * vmbus_driver_register()
@@ -1104,6 +1105,85 @@ static int vmbus_acpi_remove(struct acpi_device *device)
        return 0;
 }
 
+/**
+ * vmbus_allocate_mmio() - Pick a memory-mapped I/O range.
+ * @new:               If successful, supplied a pointer to the
+ *                     allocated MMIO space.
+ * @device_obj:                Identifies the caller
+ * @min:               Minimum guest physical address of the
+ *                     allocation
+ * @max:               Maximum guest physical address
+ * @size:              Size of the range to be allocated
+ * @align:             Alignment of the range to be allocated
+ * @fb_overlap_ok:     Whether this allocation can be allowed
+ *                     to overlap the video frame buffer.
+ *
+ * This function walks the resources granted to VMBus by the
+ * _CRS object in the ACPI namespace underneath the parent
+ * "bridge" whether that's a root PCI bus in the Generation 1
+ * case or a Module Device in the Generation 2 case.  It then
+ * attempts to allocate from the global MMIO pool in a way that
+ * matches the constraints supplied in these parameters and by
+ * that _CRS.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
+                       resource_size_t min, resource_size_t max,
+                       resource_size_t size, resource_size_t align,
+                       bool fb_overlap_ok)
+{
+       struct resource *iter;
+       resource_size_t range_min, range_max, start, local_min, local_max;
+       const char *dev_n = dev_name(&device_obj->device);
+       u32 fb_end = screen_info.lfb_base + (screen_info.lfb_size << 1);
+       int i;
+
+       for (iter = hyperv_mmio; iter; iter = iter->sibling) {
+               if ((iter->start >= max) || (iter->end <= min))
+                       continue;
+
+               range_min = iter->start;
+               range_max = iter->end;
+
+               /* If this range overlaps the frame buffer, split it into
+                  two tries. */
+               for (i = 0; i < 2; i++) {
+                       local_min = range_min;
+                       local_max = range_max;
+                       if (fb_overlap_ok || (range_min >= fb_end) ||
+                           (range_max <= screen_info.lfb_base)) {
+                               i++;
+                       } else {
+                               if ((range_min <= screen_info.lfb_base) &&
+                                   (range_max >= screen_info.lfb_base)) {
+                                       /*
+                                        * The frame buffer is in this window,
+                                        * so trim this into the part that
+                                        * preceeds the frame buffer.
+                                        */
+                                       local_max = screen_info.lfb_base - 1;
+                                       range_min = fb_end;
+                               } else {
+                                       range_min = fb_end;
+                                       continue;
+                               }
+                       }
+
+                       start = (local_min + align - 1) & ~(align - 1);
+                       for (; start + size - 1 <= local_max; start += align) {
+                               *new = request_mem_region_exclusive(start, size,
+                                                                   dev_n);
+                               if (*new)
+                                       return 0;
+                       }
+               }
+       }
+
+       return -ENXIO;
+}
+EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
+
 static int vmbus_acpi_add(struct acpi_device *device)
 {
        acpi_status result;
index b54ee1c05a5f798920c7d2c989b596d349768f15..e2451bdb4525d50fbd3de1aab743c51f7b05cef5 100644 (file)
@@ -213,7 +213,7 @@ struct synthvid_msg {
 
 struct hvfb_par {
        struct fb_info *info;
-       struct resource mem;
+       struct resource *mem;
        bool fb_ready; /* fb device is ready */
        struct completion wait;
        u32 synthvid_version;
@@ -677,26 +677,18 @@ static void hvfb_get_option(struct fb_info *info)
 
 
 /* Get framebuffer memory from Hyper-V video pci space */
-static int hvfb_getmem(struct fb_info *info)
+static int hvfb_getmem(struct hv_device *hdev, struct fb_info *info)
 {
        struct hvfb_par *par = info->par;
        struct pci_dev *pdev  = NULL;
        void __iomem *fb_virt;
        int gen2vm = efi_enabled(EFI_BOOT);
+       resource_size_t pot_start, pot_end;
        int ret;
 
-       par->mem.name = KBUILD_MODNAME;
-       par->mem.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
        if (gen2vm) {
-               ret = allocate_resource(hyperv_mmio, &par->mem,
-                                       screen_fb_size,
-                                       0, -1,
-                                       screen_fb_size,
-                                       NULL, NULL);
-               if (ret != 0) {
-                       pr_err("Unable to allocate framebuffer memory\n");
-                       return -ENODEV;
-               }
+               pot_start = 0;
+               pot_end = -1;
        } else {
                pdev = pci_get_device(PCI_VENDOR_ID_MICROSOFT,
                              PCI_DEVICE_ID_HYPERV_VIDEO, NULL);
@@ -709,16 +701,18 @@ static int hvfb_getmem(struct fb_info *info)
                    pci_resource_len(pdev, 0) < screen_fb_size)
                        goto err1;
 
-               par->mem.end = pci_resource_end(pdev, 0);
-               par->mem.start = par->mem.end - screen_fb_size + 1;
-               ret = request_resource(&pdev->resource[0], &par->mem);
-               if (ret != 0) {
-                       pr_err("Unable to request framebuffer memory\n");
-                       goto err1;
-               }
+               pot_end = pci_resource_end(pdev, 0);
+               pot_start = pot_end - screen_fb_size + 1;
+       }
+
+       ret = vmbus_allocate_mmio(&par->mem, hdev, pot_start, pot_end,
+                                 screen_fb_size, 0x100000, true);
+       if (ret != 0) {
+               pr_err("Unable to allocate framebuffer memory\n");
+               goto err1;
        }
 
-       fb_virt = ioremap(par->mem.start, screen_fb_size);
+       fb_virt = ioremap(par->mem->start, screen_fb_size);
        if (!fb_virt)
                goto err2;
 
@@ -736,7 +730,7 @@ static int hvfb_getmem(struct fb_info *info)
                info->apertures->ranges[0].size = pci_resource_len(pdev, 0);
        }
 
-       info->fix.smem_start = par->mem.start;
+       info->fix.smem_start = par->mem->start;
        info->fix.smem_len = screen_fb_size;
        info->screen_base = fb_virt;
        info->screen_size = screen_fb_size;
@@ -749,7 +743,8 @@ static int hvfb_getmem(struct fb_info *info)
 err3:
        iounmap(fb_virt);
 err2:
-       release_resource(&par->mem);
+       release_mem_region(par->mem->start, screen_fb_size);
+       par->mem = NULL;
 err1:
        if (!gen2vm)
                pci_dev_put(pdev);
@@ -763,7 +758,8 @@ static void hvfb_putmem(struct fb_info *info)
        struct hvfb_par *par = info->par;
 
        iounmap(info->screen_base);
-       release_resource(&par->mem);
+       release_mem_region(par->mem->start, screen_fb_size);
+       par->mem = NULL;
 }
 
 
@@ -794,7 +790,7 @@ static int hvfb_probe(struct hv_device *hdev,
                goto error1;
        }
 
-       ret = hvfb_getmem(info);
+       ret = hvfb_getmem(hdev, info);
        if (ret) {
                pr_err("No memory for framebuffer\n");
                goto error2;
index 217e14be77b9bb5f9b5b0cfade42d7dc5b2d9328..54733d5b503e091e01825c8fd195d1173db92ef3 100644 (file)
@@ -977,6 +977,11 @@ int __must_check __vmbus_driver_register(struct hv_driver *hv_driver,
                                         const char *mod_name);
 void vmbus_driver_unregister(struct hv_driver *hv_driver);
 
+int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
+                       resource_size_t min, resource_size_t max,
+                       resource_size_t size, resource_size_t align,
+                       bool fb_overlap_ok);
+
 /**
  * VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device
  *
@@ -1233,8 +1238,6 @@ extern bool vmbus_prep_negotiate_resp(struct icmsg_hdr *,
 
 void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);
 
-extern struct resource *hyperv_mmio;
-
 /*
  * Negotiated version with the Host.
  */