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[Xen-devel] [PATCH v2 3/6] libs: add libxenhypfs

From: Juergen Gross <jgross@xxxxxxxx>

Date: Wed, 2 Oct 2019 13:20:01 +0200

Cc: Juergen Gross <jgross@xxxxxxxx>, Ian Jackson <ian.jackson@xxxxxxxxxxxxx>, Wei Liu <wl@xxxxxxx>

Delivery-date: Wed, 02 Oct 2019 11:20:21 +0000

List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

Add the new library libxenhypfs for access to the hypervisor filesystem. Signed-off-by: Juergen Gross <jgross@xxxxxxxx> Acked-by: Ian Jackson <ian.jackson@xxxxxxxxxxxxx> --- V1: - rename to libxenhypfs - add xenhypfs_write() --- tools/Rules.mk | 6 + tools/libs/Makefile | 1 + tools/libs/hypfs/Makefile | 14 ++ tools/libs/hypfs/core.c | 252 ++++++++++++++++++++++++++++++++++++ tools/libs/hypfs/include/xenhypfs.h | 60 +++++++++ tools/libs/hypfs/libxenhypfs.map | 9 ++ tools/libs/hypfs/xenhypfs.pc.in | 10 ++ 7 files changed, 352 insertions(+) create mode 100644 tools/libs/hypfs/Makefile create mode 100644 tools/libs/hypfs/core.c create mode 100644 tools/libs/hypfs/include/xenhypfs.h create mode 100644 tools/libs/hypfs/libxenhypfs.map create mode 100644 tools/libs/hypfs/xenhypfs.pc.in diff --git a/tools/Rules.mk b/tools/Rules.mk index cf8935d6a3..b1ebb4c96c 100644 --- a/tools/Rules.mk +++ b/tools/Rules.mk @@ -19,6 +19,7 @@ XEN_LIBXENGNTTAB = $(XEN_ROOT)/tools/libs/gnttab XEN_LIBXENCALL = $(XEN_ROOT)/tools/libs/call XEN_LIBXENFOREIGNMEMORY = $(XEN_ROOT)/tools/libs/foreignmemory XEN_LIBXENDEVICEMODEL = $(XEN_ROOT)/tools/libs/devicemodel +XEN_LIBXENHYPFS = $(XEN_ROOT)/tools/libs/hypfs XEN_LIBXC = $(XEN_ROOT)/tools/libxc XEN_XENLIGHT = $(XEN_ROOT)/tools/libxl # Currently libxlutil lives in the same directory as libxenlight @@ -134,6 +135,11 @@ SHDEPS_libxendevicemodel = $(SHLIB_libxentoollog) $(SHLIB_libxentoolcore) $(SHLI LDLIBS_libxendevicemodel = $(SHDEPS_libxendevicemodel) $(XEN_LIBXENDEVICEMODEL)/libxendevicemodel$(libextension) SHLIB_libxendevicemodel = $(SHDEPS_libxendevicemodel) -Wl,-rpath-link=$(XEN_LIBXENDEVICEMODEL) +CFLAGS_libxenhypfs = -I$(XEN_LIBXENHYPFS)/include $(CFLAGS_xeninclude) +SHDEPS_libxenhypfs = $(SHLIB_libxentoollog) $(SHLIB_libxentoolcore) $(SHLIB_xencall) +LDLIBS_libxenhypfs = $(SHDEPS_libxenhypfs) $(XEN_LIBXENHYPFS)/libxenhypfs$(libextension) +SHLIB_libxenhypfs = $(SHDEPS_libxenhypfs) -Wl,-rpath-link=$(XEN_LIBXENHYPFS) + # code which compiles against libxenctrl get __XEN_TOOLS__ and # therefore sees the unstable hypercall interfaces. CFLAGS_libxenctrl = -I$(XEN_LIBXC)/include $(CFLAGS_libxentoollog) $(CFLAGS_libxenforeignmemory) $(CFLAGS_libxendevicemodel) $(CFLAGS_xeninclude) -D__XEN_TOOLS__ diff --git a/tools/libs/Makefile b/tools/libs/Makefile index 88901e7341..69cdfb5975 100644 --- a/tools/libs/Makefile +++ b/tools/libs/Makefile @@ -9,6 +9,7 @@ SUBDIRS-y += gnttab SUBDIRS-y += call SUBDIRS-y += foreignmemory SUBDIRS-y += devicemodel +SUBDIRS-y += hypfs ifeq ($(CONFIG_RUMP),y) SUBDIRS-y := toolcore diff --git a/tools/libs/hypfs/Makefile b/tools/libs/hypfs/Makefile new file mode 100644 index 0000000000..c571597686 --- /dev/null +++ b/tools/libs/hypfs/Makefile @@ -0,0 +1,14 @@ +XEN_ROOT = $(CURDIR)/../../.. +include $(XEN_ROOT)/tools/Rules.mk + +MAJOR = 1 +MINOR = 0 +LIBNAME := hypfs +USELIBS := toollog toolcore call + +SRCS-y += core.c + +include ../libs.mk + +$(PKG_CONFIG_LOCAL): PKG_CONFIG_INCDIR = $(XEN_LIBXENHYPFS)/include +$(PKG_CONFIG_LOCAL): PKG_CONFIG_CFLAGS_LOCAL = $(CFLAGS_xeninclude) diff --git a/tools/libs/hypfs/core.c b/tools/libs/hypfs/core.c new file mode 100644 index 0000000000..edbf37f2c1 --- /dev/null +++ b/tools/libs/hypfs/core.c @@ -0,0 +1,252 @@ +/* + * Copyright (c) 2019 SUSE Software Solutions Germany GmbH + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; If not, see <http://www.gnu.org/licenses/>. + */ + +#define __XEN_TOOLS__ 1 + +#include <errno.h> +#include <stdlib.h> +#include <string.h> + +#include <xentoollog.h> +#include <xenhypfs.h> +#include <xencall.h> + +#include <xentoolcore_internal.h> + +struct xenhypfs_handle { + xentoollog_logger *logger, *logger_tofree; + unsigned int flags; + xencall_handle *xcall; +}; + +xenhypfs_handle *xenhypfs_open(xentoollog_logger *logger, + unsigned open_flags) +{ + xenhypfs_handle *fshdl = calloc(1, sizeof(*fshdl)); + + if (!fshdl) + return NULL; + + fshdl->flags = open_flags; + fshdl->logger = logger; + fshdl->logger_tofree = NULL; + + if (!fshdl->logger) { + fshdl->logger = fshdl->logger_tofree = + (xentoollog_logger*) + xtl_createlogger_stdiostream(stderr, XTL_PROGRESS, 0); + if (!fshdl->logger) + goto err; + } + + fshdl->xcall = xencall_open(fshdl->logger, 0); + if (!fshdl->xcall) + goto err; + + + return fshdl; + +err: + xtl_logger_destroy(fshdl->logger_tofree); + xencall_close(fshdl->xcall); + free(fshdl); + return NULL; +} + +int xenhypfs_close(xenhypfs_handle *fshdl) +{ + if (!fshdl) + return 0; + + xencall_close(fshdl->xcall); + xtl_logger_destroy(fshdl->logger_tofree); + free(fshdl); + return 0; +} + +static int xenhypfs_get_pathbuf(xenhypfs_handle *fshdl, const char *path, + char **path_buf) +{ + int ret = -1; + int path_sz; + + if (!fshdl) { + errno = EBADF; + goto out; + } + + path_sz = strlen(path) + 1; + if (path_sz > XEN_HYPFS_MAX_PATHLEN) + { + errno = ENAMETOOLONG; + goto out; + } + + *path_buf = xencall_alloc_buffer(fshdl->xcall, path_sz); + if (!*path_buf) { + errno = ENOMEM; + goto out; + } + strcpy(*path_buf, path); + + ret = path_sz; + + out: + return ret; +} + +static void *xenhypfs_read_any(xenhypfs_handle *fshdl, const char *path, + unsigned int cmd) +{ + char *buf = NULL, *path_buf = NULL; + int ret; + int sz, path_sz; + + ret = xenhypfs_get_pathbuf(fshdl, path, &path_buf); + if (ret < 0) + goto out; + + path_sz = ret; + + for (sz = 4096; sz > 0; sz = ret) { + if (buf) + xencall_free_buffer(fshdl->xcall, buf); + + buf = xencall_alloc_buffer(fshdl->xcall, sz); + if (!buf) { + errno = ENOMEM; + goto out; + } + + ret = xencall5(fshdl->xcall, __HYPERVISOR_hypfs_op, cmd, + (unsigned long)path_buf, path_sz, + (unsigned long)buf, sz); + } + + if (ret < 0) { + errno = -ret; + xencall_free_buffer(fshdl->xcall, buf); + buf = NULL; + goto out; + } + + out: + ret = errno; + xencall_free_buffer(fshdl->xcall, path_buf); + errno = ret; + + return buf; +} + +char *xenhypfs_read(xenhypfs_handle *fshdl, const char *path) +{ + char *buf, *ret_buf = NULL; + int ret; + + buf = xenhypfs_read_any(fshdl, path, XEN_HYPFS_OP_read_contents); + if (buf) + ret_buf = strdup(buf); + + ret = errno; + xencall_free_buffer(fshdl->xcall, buf); + errno = ret; + + return ret_buf; +} + +struct xenhypfs_dirent *xenhypfs_readdir(xenhypfs_handle *fshdl, + const char *path, + unsigned int *num_entries) +{ + void *buf, *curr; + int ret; + char *names; + struct xenhypfs_dirent *ret_buf = NULL; + unsigned int n, name_sz = 0; + struct xen_hypfs_direntry *entry; + + buf = xenhypfs_read_any(fshdl, path, XEN_HYPFS_OP_read_dir); + if (!buf) + goto out; + + curr = buf; + for (n = 1;; n++) { + entry = curr; + name_sz += strlen(entry->name) + 1; + if (!entry->off_next) + break; + + curr += entry->off_next; + } + + ret_buf = malloc(n * sizeof(*ret_buf) + name_sz); + if (!ret_buf) + goto out; + + *num_entries = n; + names = (char *)(ret_buf + n); + curr = buf; + for (n = 0; n < *num_entries; n++) { + entry = curr; + ret_buf[n].name = names; + ret_buf[n].is_dir = entry->flags & XEN_HYPFS_ISDIR; + strcpy(names, entry->name); + names += strlen(entry->name) + 1; + curr += entry->off_next; + } + + out: + ret = errno; + xencall_free_buffer(fshdl->xcall, buf); + errno = ret; + + return ret_buf; +} + +int xenhypfs_write(xenhypfs_handle *fshdl, const char *path, const char *val) +{ + char *buf = NULL, *path_buf = NULL; + int ret, saved_errno; + int sz, path_sz; + + ret = xenhypfs_get_pathbuf(fshdl, path, &path_buf); + if (ret < 0) + goto out; + + path_sz = ret; + + sz = strlen(val) + 1; + buf = xencall_alloc_buffer(fshdl->xcall, sz); + if (!buf) { + ret = -1; + errno = ENOMEM; + goto out; + } + strcpy(buf, val); + + ret = xencall5(fshdl->xcall, __HYPERVISOR_hypfs_op, + XEN_HYPFS_OP_write_contents, + (unsigned long)path_buf, path_sz, + (unsigned long)buf, sz); + + out: + saved_errno = errno; + xencall_free_buffer(fshdl->xcall, path_buf); + xencall_free_buffer(fshdl->xcall, buf); + errno = saved_errno; + return ret; +} diff --git a/tools/libs/hypfs/include/xenhypfs.h b/tools/libs/hypfs/include/xenhypfs.h new file mode 100644 index 0000000000..443221510a --- /dev/null +++ b/tools/libs/hypfs/include/xenhypfs.h @@ -0,0 +1,60 @@ +/* + * Copyright (c) 2019 SUSE Software Solutions Germany GmbH + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef XENHYPFS_H +#define XENHYPFS_H + +#include <stdbool.h> +#include <stdint.h> + +#include <xen/xen.h> +#include <xen/hypfs.h> + +/* Callers who don't care don't need to #include <xentoollog.h> */ +struct xentoollog_logger; + +typedef struct xenhypfs_handle xenhypfs_handle; + +struct xenhypfs_dirent { + char *name; + bool is_dir; +}; + +xenhypfs_handle *xenhypfs_open(struct xentoollog_logger *logger, + unsigned int open_flags); +int xenhypfs_close(xenhypfs_handle *fshdl); + +/* Returned buffer should be freed via free(). */ +char *xenhypfs_read(xenhypfs_handle *fshdl, const char *path); + +/* Returned buffer should be freed via free(). */ +struct xenhypfs_dirent *xenhypfs_readdir(xenhypfs_handle *fshdl, + const char *path, + unsigned int *num_entries); + +int xenhypfs_write(xenhypfs_handle *fshdl, const char *path, const char *val); + +#endif /* XENHYPFS_H */ + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */ diff --git a/tools/libs/hypfs/libxenhypfs.map b/tools/libs/hypfs/libxenhypfs.map new file mode 100644 index 0000000000..39c63f4367 --- /dev/null +++ b/tools/libs/hypfs/libxenhypfs.map @@ -0,0 +1,9 @@ +VERS_1.0 { + global: + xenhypfs_open; + xenhypfs_close; + xenhypfs_read; + xenhypfs_readdir; + xenhypfs_write; + local: *; /* Do not expose anything by default */ +}; diff --git a/tools/libs/hypfs/xenhypfs.pc.in b/tools/libs/hypfs/xenhypfs.pc.in new file mode 100644 index 0000000000..9cb968f0db --- /dev/null +++ b/tools/libs/hypfs/xenhypfs.pc.in @@ -0,0 +1,10 @@ +prefix=@@prefix@@ +includedir=@@incdir@@ +libdir=@@libdir@@ + +Name: Xenhypfs +Description: The Xenhypfs library for Xen hypervisor +Version: @@version@@ +Cflags: -I${includedir} @@cflagslocal@@ +Libs: @@libsflag@@${libdir} -lxenhypfs +Requires.private: xentoolcore,xentoollog,xencall -- 2.16.4 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxxx https://lists.xenproject.org/mailman/listinfo/xen-devel

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