add devobj a new memobj

kernel/Makefile.build

@@ -1,7 +1,7 @@
 IHKDIR=$(IHKBASE)/$(TARGETDIR)
 OBJS = init.o mem.o debug.o mikc.o listeners.o ap.o syscall.o cls.o host.o
 OBJS += process.o copy.o waitq.o futex.o timer.o plist.o fileobj.o shmobj.o
-OBJS += zeroobj.o procfs.o
+OBJS += zeroobj.o procfs.o devobj.o
 DEPSRCS=$(wildcard $(SRC)/*.c)
 
 CFLAGS += -I$(SRC)/include -mcmodel=kernel -D__KERNEL__

kernel/devobj.c

@@ -0,0 +1,231 @@
+/**
+ * \file devobj.c
+ *  License details are found in the file LICENSE.
+ * \brief
+ *  memory mapped device pager client
+ * \author Gou Nakamura  <go.nakamura.yw@hitachi-solutions.com>
+ */
+/*
+ * HISTORY:
+ */
+
+#if 0
+#include <ihk/cpu.h>
+#endif
+#include <ihk/debug.h>
+#include <ihk/lock.h>
+#if 0
+#include <ihk/mm.h>
+#include <ihk/types.h>
+#include <cls.h>
+#include <errno.h>
+#endif
+#include <kmalloc.h>
+#if 0
+#include <kmsg.h>
+#endif
+#include <memobj.h>
+#if 0
+#include <memory.h>
+#include <page.h>
+#endif
+#include <pager.h>
+#include <string.h>
+#include <syscall.h>
+
+#define	dkprintf(...)
+#define	ekprintf(...)	kprintf(__VA_ARGS__)
+
+struct devobj {
+	struct memobj	memobj;		/* must be first */
+	long		ref;
+	uintptr_t	handle;
+	off_t		pfn_pgoff;
+	uintptr_t	pfn_pfn;
+};
+
+static memobj_release_func_t devobj_release;
+static memobj_ref_func_t devobj_ref;
+static memobj_get_page_func_t devobj_get_page;
+
+static struct memobj_ops devobj_ops = {
+	.release =	&devobj_release,
+	.ref =		&devobj_ref,
+	.get_page =	&devobj_get_page,
+};
+
+static struct devobj *to_devobj(struct memobj *memobj)
+{
+	return (struct devobj *)memobj;
+}
+
+static struct memobj *to_memobj(struct devobj *devobj)
+{
+	return &devobj->memobj;
+}
+
+/***********************************************************************
+ * devobj
+ */
+int devobj_create(int fd, size_t len, off_t off, struct memobj **objp, int *maxprotp)
+{
+	ihk_mc_user_context_t ctx;
+	struct pager_map_result result;	// XXX: assumes contiguous physical
+	int error;
+	struct devobj *obj  = NULL;
+
+	kprintf("devobj_create(%d,%lx,%lx)\n", fd, len, off);
+	if (len > PAGE_SIZE) {
+		error = -EFBIG;
+		kprintf("devobj_create(%d,%lx,%lx):too large len. %d\n", fd, len, off, error);
+		goto out;
+	}
+
+	obj = kmalloc(sizeof(*obj), IHK_MC_AP_NOWAIT);
+	if (!obj) {
+		error = -ENOMEM;
+		kprintf("devobj_create(%d,%lx,%lx):kmalloc failed. %d\n", fd, len, off, error);
+		goto out;
+	}
+
+	ihk_mc_syscall_arg0(&ctx) = PAGER_REQ_MAP;
+	ihk_mc_syscall_arg1(&ctx) = fd;
+	ihk_mc_syscall_arg2(&ctx) = len;
+	ihk_mc_syscall_arg3(&ctx) = off;
+	ihk_mc_syscall_arg4(&ctx) = virt_to_phys(&result);
+
+	error = syscall_generic_forwarding(__NR_mmap, &ctx);
+	if (error) {
+		kprintf("devobj_create(%d,%lx,%lx):map failed. %d\n", fd, len, off, error);
+		goto out;
+	}
+	kprintf("devobj_create:handle: %lx\n", result.handle);
+	kprintf("devobj_create:maxprot: %x\n", result.maxprot);
+
+	memset(obj, 0, sizeof(*obj));
+	obj->memobj.ops = &devobj_ops;
+	obj->memobj.flags = MF_HAS_PAGER;
+	obj->handle = result.handle;
+	obj->ref = 1;
+	ihk_mc_spinlock_init(&obj->memobj.lock);
+
+	error = 0;
+	*objp = to_memobj(obj);
+	*maxprotp = result.maxprot;
+	obj = NULL;
+
+out:
+	if (obj) {
+		kfree(obj);
+	}
+	kprintf("devobj_create(%d,%lx,%lx): %d %p %x%d\n", fd, len, off, error, *objp, *maxprotp);
+	return error;
+}
+
+static void devobj_ref(struct memobj *memobj)
+{
+	struct devobj *obj = to_devobj(memobj);
+
+	kprintf("devobj_ref(%p %lx):\n", obj, obj->handle);
+	memobj_lock(&obj->memobj);
+	++obj->ref;
+	memobj_unlock(&obj->memobj);
+	return;
+}
+
+static void devobj_release(struct memobj *memobj)
+{
+	struct devobj *obj = to_devobj(memobj);
+	struct devobj *free_obj = NULL;
+	uintptr_t handle;
+
+	kprintf("devobj_release(%p %lx)\n", obj, obj->handle);
+
+	memobj_lock(&obj->memobj);
+	--obj->ref;
+	if (obj->ref <= 0) {
+		free_obj = obj;
+	}
+	handle = obj->handle;
+	memobj_unlock(&obj->memobj);
+
+	if (free_obj) {
+		int error;
+		ihk_mc_user_context_t ctx;
+
+		ihk_mc_syscall_arg0(&ctx) = PAGER_REQ_UNMAP;
+		ihk_mc_syscall_arg1(&ctx) = handle;
+		ihk_mc_syscall_arg2(&ctx) = 1;
+
+		error = syscall_generic_forwarding(__NR_mmap, &ctx);
+		if (error) {
+			kprintf("devobj_release(%p %lx):"
+					"release failed. %d\n",
+					free_obj, handle, error);
+			/* through */
+		}
+
+		kfree(free_obj);
+	}
+
+	kprintf("devobj_release(%p %lx):free %p\n",
+			obj, handle, free_obj);
+	return;
+}
+
+static int devobj_get_page(struct memobj *memobj, off_t off, int p2align, uintptr_t *physp)
+{
+	const off_t pgoff = off >> PAGE_SHIFT;
+	struct devobj *obj = to_devobj(memobj);
+	int error;
+	uintptr_t pfn;
+	uintptr_t attr;
+	ihk_mc_user_context_t ctx;
+
+	kprintf("devobj_get_page(%p %lx,%lx,%d)\n", memobj, obj->handle, off, p2align);
+
+	memobj_lock(&obj->memobj);
+	pfn = obj->pfn_pfn;
+	if (!(pfn & PFN_VALID)) {
+		memobj_unlock(&obj->memobj);
+
+		ihk_mc_syscall_arg0(&ctx) = PAGER_REQ_PFN;
+		ihk_mc_syscall_arg1(&ctx) = obj->handle;
+		ihk_mc_syscall_arg2(&ctx) = pgoff << PAGE_SHIFT;
+		ihk_mc_syscall_arg3(&ctx) = virt_to_phys(&pfn);
+
+		error = syscall_generic_forwarding(__NR_mmap, &ctx);
+		if (error) {
+			kprintf("devobj_get_page(%p %lx,%lx,%d):PAGER_REQ_PFN failed. %d\n", memobj, obj->handle, off, p2align, error);
+			goto out;
+		}
+
+		if (pfn & PFN_PRESENT) {
+			/* convert remote physical into local physical */
+kprintf("devobj_get_page(%p %lx,%lx,%d):PFN_PRESENT before %#lx\n", memobj, obj->handle, off, p2align, pfn);
+			attr = pfn & ~PFN_PFN;
+			pfn = ihk_mc_map_memory(NULL, (pfn & PFN_PFN), PAGE_SIZE);
+			pfn &= PFN_PFN;
+			pfn |= attr;
+kprintf("devobj_get_page(%p %lx,%lx,%d):PFN_PRESENT after %#lx\n", memobj, obj->handle, off, p2align, pfn);
+		}
+
+		memobj_lock(&obj->memobj);
+		obj->pfn_pfn = pfn;
+		obj->pfn_pgoff = pgoff;
+	}
+	memobj_unlock(&obj->memobj);
+
+	if (!(pfn & PFN_PRESENT)) {
+		kprintf("devobj_get_page(%p %lx,%lx,%d):not present. %lx\n", memobj, obj->handle, off, p2align, pfn);
+		error = -EFAULT;
+		goto out;
+	}
+
+	error = 0;
+	*physp = pfn & PFN_PFN;
+
+out:
+	kprintf("devobj_get_page(%p %lx,%lx,%d): %d %lx\n", memobj, obj->handle, off, p2align, error, *physp);
+	return error;
+}

kernel/include/memobj.h

@@ -104,5 +104,6 @@ static inline int memobj_has_pager(struct memobj *obj)
 int fileobj_create(int fd, struct memobj **objp, int *maxprotp);
 int shmobj_create(struct shmid_ds *ds, struct memobj **objp);
 int zeroobj_create(struct memobj **objp);
+int devobj_create(int fd, size_t len, off_t off, struct memobj **objp, int *maxprotp);
 
 #endif /* HEADER_MEMOBJ_H */