feat: 增加mount的MS_RDONLY标志的支持

增加mount的MS_RDONLY标志的支持，并修改vfs主要接口相关支持

Close #I3Z1W6
Signed-off-by: NFar <yesiyuan2@huawei.com>

fs/mount/fs_mount.c

@@ -255,6 +255,7 @@ int mount(const char *source, const char *target,
 #endif
 
   mnt = MountAlloc(mountpt_vnode, (struct MountOps*)mops);
+  mnt->mountFlags = mountflags;
 
   mountpt_vnode->useCount++;
   ret = mops->Mount(mnt, device, data);
@@ -280,7 +281,6 @@ int mount(const char *source, const char *target,
   mnt->vnodeBeCovered->flag |= VNODE_FLAG_MOUNT_ORIGIN;
   mnt->vnodeCovered->flag |= VNODE_FLAG_MOUNT_NEW;
   mnt->ops = mops;
-  mnt->mountFlags = mountflags;
   if (target && (strlen(target) != 0))
     {
       ret = strcpy_s(mnt->pathName, PATH_MAX, target);

fs/vfs/fs_link.c

@@ -38,6 +38,7 @@ int do_link(int oldfd, const char *oldpath, int newfd, const char *newpath, int
   struct Vnode *new_parent_vnode = NULL;
   struct Vnode *new_vnode = NULL;
   struct Vnode *old_vnode = NULL;
+  struct Mount *mount = NULL;
   char *fulloldpath = NULL;
   char *fullnewpath = NULL;
   char *newname = NULL;
@@ -91,6 +92,13 @@ int do_link(int oldfd, const char *oldpath, int newfd, const char *newpath, int
         }
     }
 
+  mount = old_vnode->originMount;
+  if ((mount != NULL) && (mount->mountFlags & MS_RDONLY))
+    {
+      ret = -EROFS;
+      goto errout_with_vnode;
+    }
+
   if (old_vnode->type != VNODE_TYPE_REG && old_vnode->type != VNODE_TYPE_LNK)
     {
       ret = -EPERM;

fs/vfs/fs_mkdir.c

@@ -54,6 +54,7 @@ int do_mkdir(int dirfd, const char *pathname, mode_t mode)
 {
   struct Vnode *parentVnode = NULL;
   struct Vnode *vnode = NULL;
+  struct Mount *mount = NULL;
   int ret;
   char *fullpath = NULL;
   char *relativepath = NULL;
@@ -109,6 +110,13 @@ int do_mkdir(int dirfd, const char *pathname, mode_t mode)
       ret = -ENOENT;
       goto errout_with_lock;
     }
+  mount = parentVnode->originMount;
+  if ((mount != NULL) && (mount->mountFlags & MS_RDONLY))
+    {
+      ret = -EROFS;
+      goto errout_with_lock;
+    }
+
   parentVnode->useCount++;
 
   if (VfsVnodePermissionCheck(parentVnode, (WRITE_OP | EXEC_OP)))

fs/vfs/fs_open.c

@@ -177,7 +177,8 @@ int fp_open(int dirfd, const char *path, int oflags, mode_t mode)
           goto errout;
         }
 #ifdef LOSCFG_FS_VFS_BLOCK_DEVICE
-      if (vnode->type == VNODE_TYPE_BLK) {
+      if (vnode->type == VNODE_TYPE_BLK)
+        {
           VnodeDrop();
           fd = block_proxy(fullpath, oflags);
           if (fd < 0)
@@ -186,8 +187,15 @@ int fp_open(int dirfd, const char *path, int oflags, mode_t mode)
               goto errout;
             }
          return fd;
-      }
+        }
 #endif
+      if ((vnode->originMount) && (vnode->originMount->mountFlags & MS_RDONLY) &&
+          (((oflags & O_ACCMODE) != O_RDONLY) || (oflags & O_TRUNC)))
+        {
+          ret = -EROFS;
+          VnodeDrop();
+          goto errout;
+        }
       if ((oflags & O_CREAT) && (oflags & O_EXCL))
         {
           ret = -EEXIST;
@@ -212,6 +220,12 @@ int fp_open(int dirfd, const char *path, int oflags, mode_t mode)
   if ((ret != OK) && (oflags & O_CREAT) && vnode)
     {
       /* if file not exist, but parent dir of the file is exist */
+      if ((vnode->originMount) && (vnode->originMount->mountFlags & MS_RDONLY))
+        {
+          ret = -EROFS;
+          VnodeDrop();
+          goto errout;
+        }
       if (VfsVnodePermissionCheck(vnode, (WRITE_OP | EXEC_OP)))
         {
           ret = -EACCES;

fs/vfs/fs_rename.c

@@ -58,6 +58,10 @@ static int check_rename_target(struct Vnode *old_vnode, struct Vnode *old_parent
     {
       return -ENOENT;
     }
+  if ((new_parent_vnode->originMount) && (new_parent_vnode->originMount->mountFlags & MS_RDONLY))
+    {
+      return -EROFS;
+    }
   if (old_vnode->type != VNODE_TYPE_DIR && old_vnode->type != VNODE_TYPE_REG)
     {
       return -EACCES;

fs/vfs/fs_rmdir.c

@@ -46,16 +46,23 @@
 #include "sys/stat.h"
 #include "string.h"
 #include "limits.h"
+#include "fs/mount.h"
 
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
-static int check_target(struct Vnode *vnode, char *name) {
+static int check_target(struct Vnode *vnode, char *name)
+{
   if (vnode == NULL)
     {
       return -ENOENT;
     }
 
+  if ((vnode->originMount) && (vnode->originMount->mountFlags & MS_RDONLY))
+    {
+      return -EROFS;
+    }
+
   if (vnode->type != VNODE_TYPE_DIR)
     {
       return -ENOTDIR;

fs/vfs/fs_symlink.c

@@ -93,6 +93,7 @@ int do_symlink(const char *target, int newfd, const char *path)
   struct Vnode *new_vnode = NULL;
   char *fullpath = NULL;
   char *newname = NULL;
+  struct Mount *mount = NULL;
   int ret;
 
   if (!path)
@@ -134,6 +135,12 @@ int do_symlink(const char *target, int newfd, const char *path)
       ret = -ENOSYS;
       goto errout_with_vnode;
     }
+  mount = parent_vnode->originMount;
+  if ((mount != NULL) && (mount->mountFlags & MS_RDONLY))
+    {
+      ret = -EROFS;
+      goto errout_with_vnode;
+    }
 
   parent_vnode->useCount++;
   ret = parent_vnode->vop->Symlink(parent_vnode, &new_vnode, (const char *)newname, (const char *)target);

fs/vfs/fs_unlink.c

@@ -45,6 +45,7 @@
 
 #include "vnode.h"
 #include "stdlib.h"
+#include "fs/mount.h"
 
 /****************************************************************************
  * Private Functions
@@ -56,6 +57,11 @@ static int check_target(struct Vnode *vnode)
       return -EISDIR;
     }
 
+  if ((vnode->originMount) && (vnode->originMount->mountFlags & MS_RDONLY))
+    {
+      return -EROFS;
+    }
+
   if (vnode->useCount > 0)
     {
       return -EBUSY;