fileobj/devobj: record path name (originally by Takagi-san)

executer/kernel/mcctrl/syscall.c

@@ -1182,6 +1182,7 @@ struct pager_create_result {
 	int		maxprot;
 	uint32_t flags;
 	size_t size;
+	char path[PATH_MAX];
 };
 
 enum {
@@ -1200,6 +1201,33 @@ enum {
 	MF_END
 };
 
+static int pager_get_path(struct file *file, char *path) {
+	int error = 0;
+	char *pathbuf, *fullpath;
+
+	pathbuf = kmalloc(PATH_MAX, GFP_TEMPORARY);
+	if (!pathbuf) {
+		printk("%s: ERROR: allocating path\n", __FUNCTION__);
+		error = -ENOMEM;
+		goto out;
+	}
+
+	fullpath = d_path(&file->f_path, pathbuf, PATH_MAX);
+	if (!IS_ERR(fullpath)) {
+		memcpy(path, fullpath, strlen(fullpath));
+	}
+	else {
+		path[0] = 0;
+	}
+
+out:
+	if (pathbuf) {
+		kfree(pathbuf);
+	}
+	return error;
+}
+
+
 static int pager_req_create(ihk_os_t os, int fd, uintptr_t result_pa)
 {
 	ihk_device_t dev = ihk_os_to_dev(os);
@@ -1333,6 +1361,7 @@ found:
 	phys = ihk_device_map_memory(dev, result_pa, sizeof(*resp));
 	resp = ihk_device_map_virtual(dev, phys, sizeof(*resp), NULL, 0);
 	if (!resp) {
+		ihk_device_unmap_memory(dev, phys, sizeof(*resp));
 		printk("%s: ERROR: invalid response structure address\n",
 			__FUNCTION__);
 		error = -EINVAL;
@@ -1343,10 +1372,18 @@ found:
 	resp->maxprot = maxprot;
 	resp->flags = mf_flags;
 	resp->size = st.size;
+
+	error = pager_get_path(file, resp->path);
+	if (error) {
+		goto out_unmap;
+	}
+
+	error = 0;
+
+out_unmap:
 	ihk_device_unmap_virtual(dev, resp, sizeof(*resp));
 	ihk_device_unmap_memory(dev, phys, sizeof(*resp));
 
-	error = 0;
 out:
 	if (newpager) {
 		kfree(newpager);
@@ -1578,6 +1615,7 @@ struct pager_map_result {
 	uintptr_t	handle;
 	int		maxprot;
 	int8_t		padding[4];
+    char path[PATH_MAX];
 };
 
 static int pager_req_map(ihk_os_t os, int fd, size_t len, off_t off,
@@ -1665,6 +1703,7 @@ static int pager_req_map(ihk_os_t os, int fd, size_t len, off_t off,
 	phys = ihk_device_map_memory(dev, result_rpa, sizeof(*resp));
 	resp = ihk_device_map_virtual(dev, phys, sizeof(*resp), NULL, 0);
 	if (!resp) {
+		ihk_device_unmap_memory(dev, phys, sizeof(*resp));
 		printk("%s: ERROR: invalid response structure address\n",
 			__FUNCTION__);
 		error = -EINVAL;
@@ -1673,13 +1712,16 @@ static int pager_req_map(ihk_os_t os, int fd, size_t len, off_t off,
 
 	resp->handle = (uintptr_t)pager;
 	resp->maxprot = maxprot;
-	ihk_device_unmap_virtual(dev, resp, sizeof(*resp));
-	ihk_device_unmap_memory(dev, phys, sizeof(*resp));
+
+	error = pager_get_path(file, resp->path);
+	if (error) {
+		goto out_unmap;
+	}
 
 	error = down_interruptible(&ppd->devobj_pager_lock);
 	if (error) {
 		error = -EINTR;
-		goto out;
+		goto out_unmap;
 	}
 
 	list_add_tail(&pager->list, &ppd->devobj_pager_list);
@@ -1688,6 +1730,10 @@ static int pager_req_map(ihk_os_t os, int fd, size_t len, off_t off,
 	pager = 0;
 	error = 0;
 
+out_unmap:
+	ihk_device_unmap_virtual(dev, resp, sizeof(*resp));
+	ihk_device_unmap_memory(dev, phys, sizeof(*resp));
+
 out:
 	if (file) {
 		fput(file);

kernel/devobj.c

@@ -136,6 +136,18 @@ int devobj_create(int fd, size_t len, off_t off, struct memobj **objp, int *maxp
 	obj->memobj.flags = MF_HAS_PAGER | MF_DEV_FILE;
 	obj->memobj.size = len;
 	obj->handle = result.handle;
+
+	dkprintf("%s: path=%s\n", __FUNCTION__, result.path);
+	if (result.path[0]) {
+		obj->memobj.path = kmalloc(PATH_MAX, IHK_MC_AP_NOWAIT);
+		if (!obj->memobj.path) {
+			error = -ENOMEM;
+			kprintf("%s: ERROR: Out of memory\n", __FUNCTION__);
+			goto out;
+		}
+		strncpy(obj->memobj.path, result.path, PATH_MAX);
+	}
+
 	obj->ref = 1;
 	obj->pfn_pgoff = off / PAGE_SIZE;
 	obj->npages = npages;
@@ -217,6 +229,11 @@ static void devobj_release(struct memobj *memobj)
 			ihk_mc_free_pages(obj->pfn_table, pfn_npages);
 #endif /*POSTK_DEBUG_TEMP_FIX_36*/
 		}
+
+		if (to_memobj(free_obj)->path) {
+			kfree(to_memobj(free_obj)->path);
+		}
+
 		kfree(free_obj);
 	}
 

kernel/fileobj.c

@@ -223,6 +223,18 @@ int fileobj_create(int fd, struct memobj **objp, int *maxprotp, uintptr_t virt_a
 	newobj->memobj.ops = &fileobj_ops;
 	newobj->memobj.flags = MF_HAS_PAGER | MF_REG_FILE;
 	newobj->handle = result.handle;
+	dkprintf("%s: path=%s\n", __FUNCTION__, result.path);
+
+	if (result.path[0]) {
+		newobj->memobj.path = kmalloc(PATH_MAX, IHK_MC_AP_NOWAIT);
+		if (!newobj->memobj.path) {
+			error = -ENOMEM;
+			kprintf("%s: error: allocating path\n", __FUNCTION__);
+			goto out;
+		}
+		strncpy(newobj->memobj.path, result.path, PATH_MAX);
+	}
+
 	newobj->sref = 1;
 	newobj->cref = 1;
 	fileobj_page_hash_init(newobj);
@@ -434,6 +446,10 @@ static void fileobj_release(struct memobj *memobj)
 			kfree(to_memobj(free_obj)->pages);
 		}
 
+		if (to_memobj(free_obj)->path) {
+			kfree(to_memobj(free_obj)->path);
+		}
+
 		obj_list_remove(free_obj);
 		mcs_lock_unlock_noirq(&fileobj_list_lock, &node);
 		kfree(free_obj);

kernel/include/memobj.h

@@ -61,6 +61,7 @@ struct memobj {
 	/* For pre-mapped memobjects */
 	void **pages;
 	int nr_pages;
+	char *path;
 };
 
 typedef void memobj_release_func_t(struct memobj *obj);

kernel/include/pager.h

@@ -13,6 +13,7 @@
 #define HEADER_PAGER_H
 
 #include <ihk/types.h>
+#include <limits.h>
 
 enum pager_op {
 	PAGER_REQ_CREATE =	0x0001,
@@ -32,6 +33,7 @@ struct pager_create_result {
 	int		maxprot;
 	uint32_t flags;
 	size_t size;
+	char path[PATH_MAX];
 };
 
 /*
@@ -46,6 +48,7 @@ struct pager_map_result {
 	uintptr_t	handle;
 	int		maxprot;
 	int8_t		padding[4];
+	char path[PATH_MAX];
 };
 
 /* for pager_req_pfn() */