From: Ian Campbell Ian.Campbell@citrix.com
Do not apply!
This is a simple, hacky implementation of xen_remap_domain_mfn_range, using XENMAPSPACE_gmfn_foreign.
It should use same interface as hybrid x86.
Changes in v2:
- retain binary compatibility in xen_add_to_physmap: use a union.
Signed-off-by: Ian Campbell Ian.Campbell@citrix.com Signed-off-by: Stefano Stabellini stefano.stabellini@eu.citrix.com --- arch/arm/xen/enlighten.c | 79 +++++++++++++++++++++++++++++++++++++++- drivers/xen/privcmd.c | 16 +++++---- drivers/xen/xenfs/super.c | 7 ++++ include/xen/interface/memory.h | 15 ++++++-- 4 files changed, 105 insertions(+), 12 deletions(-)
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index c244583..20ca1e4 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -16,6 +16,10 @@ #include <linux/of.h> #include <linux/of_irq.h> #include <linux/of_address.h> +#include <linux/mm.h> +#include <linux/ioport.h> + +#include <asm/pgtable.h>
struct start_info _xen_start_info; struct start_info *xen_start_info = &_xen_start_info; @@ -38,12 +42,85 @@ EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
static __read_mostly int xen_events_irq = -1;
+#define FOREIGN_MAP_BUFFER 0x90000000UL +#define FOREIGN_MAP_BUFFER_SIZE 0x10000000UL +struct resource foreign_map_resource = { + .start = FOREIGN_MAP_BUFFER, + .end = FOREIGN_MAP_BUFFER + FOREIGN_MAP_BUFFER_SIZE, + .name = "Xen foreign map buffer", + .flags = 0, +}; + +static unsigned long foreign_map_buffer_pfn = FOREIGN_MAP_BUFFER >> PAGE_SHIFT; + +struct remap_data { + struct mm_struct *mm; + unsigned long mfn; + pgprot_t prot; +}; + +static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, + unsigned long addr, void *data) +{ + struct remap_data *rmd = data; + pte_t pte = pfn_pte(rmd->mfn, rmd->prot); + + if (rmd->mfn < 0x90010) + pr_crit("%s: ptep %p addr %#lx => %#x / %#lx\n", + __func__, ptep, addr, pte_val(pte), rmd->mfn); + + set_pte_at(rmd->mm, addr, ptep, pte); + + rmd->mfn++; + return 0; +} + int xen_remap_domain_mfn_range(struct vm_area_struct *vma, unsigned long addr, unsigned long mfn, int nr, pgprot_t prot, unsigned domid) { - return -ENOSYS; + int i, rc = 0; + struct remap_data rmd = { + .mm = vma->vm_mm, + .prot = prot, + }; + struct xen_add_to_physmap xatp = { + .domid = DOMID_SELF, + .space = XENMAPSPACE_gmfn_foreign, + + .foreign_domid = domid, + }; + + if (foreign_map_buffer_pfn + nr > ((FOREIGN_MAP_BUFFER + + FOREIGN_MAP_BUFFER_SIZE)>>PAGE_SHIFT)) { + pr_crit("RAM out of foreign map buffers...\n"); + return -EBUSY; + } + + for (i = 0; i < nr; i++) { + xatp.idx = mfn + i; + xatp.gpfn = foreign_map_buffer_pfn + i; + rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp); + if (rc != 0) { + pr_crit("foreign map add_to_physmap failed, err=%d\n", rc); + goto out; + } + } + + rmd.mfn = foreign_map_buffer_pfn; + rc = apply_to_page_range(vma->vm_mm, + addr, + (unsigned long)nr << PAGE_SHIFT, + remap_area_mfn_pte_fn, &rmd); + if (rc != 0) { + pr_crit("apply_to_page_range failed rc=%d\n", rc); + goto out; + } + + foreign_map_buffer_pfn += nr; +out: + return rc; } EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 85226cb..3e15c22 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -20,6 +20,8 @@ #include <linux/pagemap.h> #include <linux/seq_file.h> #include <linux/miscdevice.h> +#include <linux/resource.h> +#include <linux/ioport.h>
#include <asm/pgalloc.h> #include <asm/pgtable.h> @@ -196,9 +198,6 @@ static long privcmd_ioctl_mmap(void __user *udata) LIST_HEAD(pagelist); struct mmap_mfn_state state;
- if (!xen_initial_domain()) - return -EPERM; - if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd))) return -EFAULT;
@@ -286,9 +285,6 @@ static long privcmd_ioctl_mmap_batch(void __user *udata) LIST_HEAD(pagelist); struct mmap_batch_state state;
- if (!xen_initial_domain()) - return -EPERM; - if (copy_from_user(&m, udata, sizeof(m))) return -EFAULT;
@@ -365,6 +361,11 @@ static long privcmd_ioctl(struct file *file, return ret; }
+static void privcmd_close(struct vm_area_struct *vma) +{ + /* TODO: unmap VMA */ +} + static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n", @@ -375,7 +376,8 @@ static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf) }
static struct vm_operations_struct privcmd_vm_ops = { - .fault = privcmd_fault + .fault = privcmd_fault, + .close = privcmd_close, };
static int privcmd_mmap(struct file *file, struct vm_area_struct *vma) diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c index a84b53c..edbe22f 100644 --- a/drivers/xen/xenfs/super.c +++ b/drivers/xen/xenfs/super.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/fs.h> #include <linux/magic.h> +#include <linux/ioport.h>
#include <xen/xen.h>
@@ -80,6 +81,8 @@ static const struct file_operations capabilities_file_ops = { .llseek = default_llseek, };
+extern struct resource foreign_map_resource; + static int xenfs_fill_super(struct super_block *sb, void *data, int silent) { static struct tree_descr xenfs_files[] = { @@ -100,6 +103,10 @@ static int xenfs_fill_super(struct super_block *sb, void *data, int silent) &xsd_kva_file_ops, NULL, S_IRUSR|S_IWUSR); xenfs_create_file(sb, sb->s_root, "xsd_port", &xsd_port_file_ops, NULL, S_IRUSR|S_IWUSR); + rc = request_resource(&iomem_resource, &foreign_map_resource); + if (rc < 0) + pr_crit("failed to register foreign map resource\n"); + rc = 0; /* ignore */ }
return rc; diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index b66d04c..dd2ffe0 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -163,12 +163,19 @@ struct xen_add_to_physmap { /* Which domain to change the mapping for. */ domid_t domid;
- /* Number of pages to go through for gmfn_range */ - uint16_t size; + union { + /* Number of pages to go through for gmfn_range */ + uint16_t size; + /* IFF gmfn_foreign */ + domid_t foreign_domid; + };
/* Source mapping space. */ -#define XENMAPSPACE_shared_info 0 /* shared info page */ -#define XENMAPSPACE_grant_table 1 /* grant table page */ +#define XENMAPSPACE_shared_info 0 /* shared info page */ +#define XENMAPSPACE_grant_table 1 /* grant table page */ +#define XENMAPSPACE_gmfn 2 /* GMFN */ +#define XENMAPSPACE_gmfn_range 3 /* GMFN range */ +#define XENMAPSPACE_gmfn_foreign 4 /* GMFN from another guest */ unsigned int space;
/* Index into source mapping space. */