xen: introduce Kconfig ARCH_PAGING_MEMPOOL

ARM MPU system doesn't need to use paging memory pool, as MPU memory
mapping table at most takes only one 4KB page, which is enough to
manage the maximum 255 MPU memory regions, for all EL2 stage 1
translation and EL1 stage 2 translation.

Introduce ARCH_PAGING_MEMPOOL Kconfig common symbol, selected for Arm
MMU systems and x86. Removed stubs from RISC-V now that the common code
provide them and the functions are not gonna be used.

Wrap the code inside 'construct_domU' that deal with p2m paging
allocation in a new function 'domain_p2m_set_allocation', protected
by ARCH_PAGING_MEMPOOL, this is done in this way to prevent polluting
the former function with #ifdefs and improve readability

Introduce arch_{get,set}_paging_mempool_size stubs for architecture
with !ARCH_PAGING_MEMPOOL.

Remove 'struct paging_domain' from Arm 'struct arch_domain' when the
field is not required.

Signed-off-by: Penny Zheng <penny.zheng@arm.com>
Signed-off-by: Wei Chen <wei.chen@arm.com>
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Michal Orzel <michal.orzel@amd.com> # arm
Reviewed-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> # riscv
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Jan Beulich <jbeulich@suse.com>

diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index 7a7658812d0e2dfecfd9dbf961a1ecc0d0eab872..565f28833118c617484d5421c84330283c0a81ba 100644 (file)
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -75,6 +75,7 @@ choice
 
 config MMU
        bool "MMU"
+       select ARCH_PAGING_MEMPOOL
        select HAS_LLC_COLORING if !NUMA && ARM_64
        select HAS_PMAP
        select HAS_VMAP

diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c
index 573b0d25ae412d8cbe1f8fdb428cc211e53a60d3..bd15563750e88c31312bd4f17cbaac9c641fbc9c 100644 (file)
--- a/xen/arch/arm/dom0less-build.c
+++ b/xen/arch/arm/dom0less-build.c
@@ -673,21 +673,6 @@ static int __init prepare_dtb_domU(struct domain *d, struct kernel_info *kinfo)
     return -EINVAL;
 }
 
-static unsigned long __init domain_p2m_pages(unsigned long maxmem_kb,
-                                             unsigned int smp_cpus)
-{
-    /*
-     * Keep in sync with libxl__get_required_paging_memory().
-     * 256 pages (1MB) per vcpu, plus 1 page per MiB of RAM for the P2M map,
-     * plus 128 pages to cover extended regions.
-     */
-    unsigned long memkb = 4 * (256 * smp_cpus + (maxmem_kb / 1024) + 128);
-
-    BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
-
-    return DIV_ROUND_UP(memkb, 1024) << (20 - PAGE_SHIFT);
-}
-
 static int __init alloc_xenstore_evtchn(struct domain *d)
 {
     evtchn_alloc_unbound_t alloc;
@@ -841,6 +826,49 @@ static void __init domain_vcpu_affinity(struct domain *d,
     }
 }
 
+#ifdef CONFIG_ARCH_PAGING_MEMPOOL
+static unsigned long __init domain_p2m_pages(unsigned long maxmem_kb,
+                                             unsigned int smp_cpus)
+{
+    /*
+     * Keep in sync with libxl__get_required_paging_memory().
+     * 256 pages (1MB) per vcpu, plus 1 page per MiB of RAM for the P2M map,
+     * plus 128 pages to cover extended regions.
+     */
+    unsigned long memkb = 4 * (256 * smp_cpus + (maxmem_kb / 1024) + 128);
+
+    BUILD_BUG_ON(PAGE_SIZE != SZ_4K);
+
+    return DIV_ROUND_UP(memkb, 1024) << (20 - PAGE_SHIFT);
+}
+
+static int __init domain_p2m_set_allocation(struct domain *d, uint64_t mem,
+                                            const struct dt_device_node *node)
+{
+    unsigned long p2m_pages;
+    uint32_t p2m_mem_mb;
+    int rc;
+
+    rc = dt_property_read_u32(node, "xen,domain-p2m-mem-mb", &p2m_mem_mb);
+    /* If xen,domain-p2m-mem-mb is not specified, use the default value. */
+    p2m_pages = rc ?
+                p2m_mem_mb << (20 - PAGE_SHIFT) :
+                domain_p2m_pages(mem, d->max_vcpus);
+
+    spin_lock(&d->arch.paging.lock);
+    rc = p2m_set_allocation(d, p2m_pages, NULL);
+    spin_unlock(&d->arch.paging.lock);
+
+    return rc;
+}
+#else /* !CONFIG_ARCH_PAGING_MEMPOOL */
+static inline int domain_p2m_set_allocation(struct domain *d, uint64_t mem,
+                                            const struct dt_device_node *node)
+{
+    return 0;
+}
+#endif /* CONFIG_ARCH_PAGING_MEMPOOL */
+
 static int __init construct_domU(struct domain *d,
                                  const struct dt_device_node *node)
 {
@@ -848,8 +876,6 @@ static int __init construct_domU(struct domain *d,
     const char *dom0less_enhanced;
     int rc;
     u64 mem;
-    u32 p2m_mem_mb;
-    unsigned long p2m_pages;
 
     rc = dt_property_read_u64(node, "memory", &mem);
     if ( !rc )
@@ -859,15 +885,7 @@ static int __init construct_domU(struct domain *d,
     }
     kinfo.unassigned_mem = (paddr_t)mem * SZ_1K;
 
-    rc = dt_property_read_u32(node, "xen,domain-p2m-mem-mb", &p2m_mem_mb);
-    /* If xen,domain-p2m-mem-mb is not specified, use the default value. */
-    p2m_pages = rc ?
-                p2m_mem_mb << (20 - PAGE_SHIFT) :
-                domain_p2m_pages(mem, d->max_vcpus);
-
-    spin_lock(&d->arch.paging.lock);
-    rc = p2m_set_allocation(d, p2m_pages, NULL);
-    spin_unlock(&d->arch.paging.lock);
+    rc = domain_p2m_set_allocation(d, mem, node);
     if ( rc != 0 )
         return rc;
 

diff --git a/xen/arch/arm/include/asm/domain.h b/xen/arch/arm/include/asm/domain.h
index 50b6a4b009820f1cf90c0ea674fdd50a486add1b..a3487ca713031edb234540284ca3f4b7ba2fdc69 100644 (file)
--- a/xen/arch/arm/include/asm/domain.h
+++ b/xen/arch/arm/include/asm/domain.h
@@ -75,7 +75,9 @@ struct arch_domain
 
     struct hvm_domain hvm;
 
+#ifdef CONFIG_ARCH_PAGING_MEMPOOL
     struct paging_domain paging;
+#endif
 
     struct vmmio vmmio;
 

diff --git a/xen/arch/riscv/stubs.c b/xen/arch/riscv/stubs.c
index caa133de84c5a224341f0d2ed0013fc414311d2b..a1d64534cd9cd7947e67972459c9d79b6bd35e22 100644 (file)
--- a/xen/arch/riscv/stubs.c
+++ b/xen/arch/riscv/stubs.c
@@ -333,11 +333,6 @@ void arch_do_physinfo(struct xen_sysctl_physinfo *pi)
 
 /* p2m.c */
 
-int arch_set_paging_mempool_size(struct domain *d, uint64_t size)
-{
-    BUG_ON("unimplemented");
-}
-
 int unmap_mmio_regions(struct domain *d,
                        gfn_t start_gfn,
                        unsigned long nr,
@@ -360,12 +355,6 @@ int set_foreign_p2m_entry(struct domain *d, const struct domain *fd,
     BUG_ON("unimplemented");
 }
 
-/* Return the size of the pool, in bytes. */
-int arch_get_paging_mempool_size(struct domain *d, uint64_t *size)
-{
-    BUG_ON("unimplemented");
-}
-
 int guest_physmap_remove_page(struct domain *d, gfn_t gfn, mfn_t mfn,
                               unsigned int page_order)
 {

diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
index 18efdb2e3130bef487504b9e85649053a309d9e1..de2fa37f088d5b355c5377f043a5989a0910e61c 100644 (file)
--- a/xen/arch/x86/Kconfig
+++ b/xen/arch/x86/Kconfig
@@ -9,6 +9,7 @@ config X86
        select ACPI_NUMA
        select ALTERNATIVE_CALL
        select ARCH_MAP_DOMAIN_PAGE
+       select ARCH_PAGING_MEMPOOL
        select ARCH_SUPPORTS_INT128
        imply CORE_PARKING
        select FUNCTION_ALIGNMENT_16B

diff --git a/xen/common/Kconfig b/xen/common/Kconfig
index a6aa2c5c145610cfaf92d68f98b45d49328118fe..218357d593b7db97f6cebb11e4a193191c489637 100644 (file)
--- a/xen/common/Kconfig
+++ b/xen/common/Kconfig
@@ -44,6 +44,9 @@ config ALTERNATIVE_CALL
 config ARCH_MAP_DOMAIN_PAGE
        bool
 
+config ARCH_PAGING_MEMPOOL
+       bool
+
 config GENERIC_BUG_FRAME
        bool
 

diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
index 83069de5011877f0bfdb9321c6f92a6dc11537c6..a34daa7d10abc4398f2b07d723b3bd11a21c4f07 100644 (file)
--- a/xen/include/xen/domain.h
+++ b/xen/include/xen/domain.h
@@ -2,6 +2,7 @@
 #ifndef __XEN_DOMAIN_H__
 #define __XEN_DOMAIN_H__
 
+#include <xen/errno.h>
 #include <xen/numa.h>
 #include <xen/types.h>
 
@@ -114,9 +115,25 @@ void arch_get_info_guest(struct vcpu *v, vcpu_guest_context_u c);
 int arch_initialise_vcpu(struct vcpu *v, XEN_GUEST_HANDLE_PARAM(void) arg);
 int default_initialise_vcpu(struct vcpu *v, XEN_GUEST_HANDLE_PARAM(void) arg);
 
+#ifdef CONFIG_ARCH_PAGING_MEMPOOL
+
 int arch_get_paging_mempool_size(struct domain *d, uint64_t *size /* bytes */);
 int arch_set_paging_mempool_size(struct domain *d, uint64_t size /* bytes */);
 
+#else /* !CONFIG_ARCH_PAGING_MEMPOOL */
+
+static inline int arch_get_paging_mempool_size(struct domain *d, uint64_t *size)
+{
+    return -EOPNOTSUPP;
+}
+
+static inline int arch_set_paging_mempool_size(struct domain *d, uint64_t size)
+{
+    return -EOPNOTSUPP;
+}
+
+#endif /* CONFIG_ARCH_PAGING_MEMPOOL */
+
 bool update_runstate_area(struct vcpu *v);
 
 int domain_relinquish_resources(struct domain *d);