[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/fs/sdcardfs/lookup.c b/src/kernel/linux/v4.14/fs/sdcardfs/lookup.c
new file mode 100644
index 0000000..73179ce
--- /dev/null
+++ b/src/kernel/linux/v4.14/fs/sdcardfs/lookup.c
@@ -0,0 +1,470 @@
+/*
+ * fs/sdcardfs/lookup.c
+ *
+ * Copyright (c) 2013 Samsung Electronics Co. Ltd
+ * Authors: Daeho Jeong, Woojoong Lee, Seunghwan Hyun,
+ * Sunghwan Yun, Sungjong Seo
+ *
+ * This program has been developed as a stackable file system based on
+ * the WrapFS which written by
+ *
+ * Copyright (c) 1998-2011 Erez Zadok
+ * Copyright (c) 2009 Shrikar Archak
+ * Copyright (c) 2003-2011 Stony Brook University
+ * Copyright (c) 2003-2011 The Research Foundation of SUNY
+ *
+ * This file is dual licensed. It may be redistributed and/or modified
+ * under the terms of the Apache 2.0 License OR version 2 of the GNU
+ * General Public License.
+ */
+
+#include "sdcardfs.h"
+#include "linux/delay.h"
+
+/* The dentry cache is just so we have properly sized dentries */
+static struct kmem_cache *sdcardfs_dentry_cachep;
+
+int sdcardfs_init_dentry_cache(void)
+{
+ sdcardfs_dentry_cachep =
+ kmem_cache_create("sdcardfs_dentry",
+ sizeof(struct sdcardfs_dentry_info),
+ 0, SLAB_RECLAIM_ACCOUNT, NULL);
+
+ return sdcardfs_dentry_cachep ? 0 : -ENOMEM;
+}
+
+void sdcardfs_destroy_dentry_cache(void)
+{
+ kmem_cache_destroy(sdcardfs_dentry_cachep);
+}
+
+void free_dentry_private_data(struct dentry *dentry)
+{
+ kmem_cache_free(sdcardfs_dentry_cachep, dentry->d_fsdata);
+ dentry->d_fsdata = NULL;
+}
+
+/* allocate new dentry private data */
+int new_dentry_private_data(struct dentry *dentry)
+{
+ struct sdcardfs_dentry_info *info = SDCARDFS_D(dentry);
+
+ /* use zalloc to init dentry_info.lower_path */
+ info = kmem_cache_zalloc(sdcardfs_dentry_cachep, GFP_ATOMIC);
+ if (!info)
+ return -ENOMEM;
+
+ spin_lock_init(&info->lock);
+ dentry->d_fsdata = info;
+
+ return 0;
+}
+
+struct inode_data {
+ struct inode *lower_inode;
+ userid_t id;
+};
+
+static int sdcardfs_inode_test(struct inode *inode, void *candidate_data/*void *candidate_lower_inode*/)
+{
+ struct inode *current_lower_inode = sdcardfs_lower_inode(inode);
+ userid_t current_userid = SDCARDFS_I(inode)->data->userid;
+
+ if (current_lower_inode == ((struct inode_data *)candidate_data)->lower_inode &&
+ current_userid == ((struct inode_data *)candidate_data)->id)
+ return 1; /* found a match */
+ else
+ return 0; /* no match */
+}
+
+static int sdcardfs_inode_set(struct inode *inode, void *lower_inode)
+{
+ /* we do actual inode initialization in sdcardfs_iget */
+ return 0;
+}
+
+struct inode *sdcardfs_iget(struct super_block *sb, struct inode *lower_inode, userid_t id)
+{
+ struct sdcardfs_inode_info *info;
+ struct inode_data data;
+ struct inode *inode; /* the new inode to return */
+
+ if (!igrab(lower_inode))
+ return ERR_PTR(-ESTALE);
+
+ data.id = id;
+ data.lower_inode = lower_inode;
+ inode = iget5_locked(sb, /* our superblock */
+ /*
+ * hashval: we use inode number, but we can
+ * also use "(unsigned long)lower_inode"
+ * instead.
+ */
+ lower_inode->i_ino, /* hashval */
+ sdcardfs_inode_test, /* inode comparison function */
+ sdcardfs_inode_set, /* inode init function */
+ &data); /* data passed to test+set fxns */
+ if (!inode) {
+ iput(lower_inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ /* if found a cached inode, then just return it (after iput) */
+ if (!(inode->i_state & I_NEW)) {
+ iput(lower_inode);
+ return inode;
+ }
+
+ /* initialize new inode */
+ info = SDCARDFS_I(inode);
+
+ inode->i_ino = lower_inode->i_ino;
+ sdcardfs_set_lower_inode(inode, lower_inode);
+
+ inode->i_version++;
+
+ /* use different set of inode ops for symlinks & directories */
+ if (S_ISDIR(lower_inode->i_mode))
+ inode->i_op = &sdcardfs_dir_iops;
+ else if (S_ISLNK(lower_inode->i_mode))
+ inode->i_op = &sdcardfs_symlink_iops;
+ else
+ inode->i_op = &sdcardfs_main_iops;
+
+ /* use different set of file ops for directories */
+ if (S_ISDIR(lower_inode->i_mode))
+ inode->i_fop = &sdcardfs_dir_fops;
+ else
+ inode->i_fop = &sdcardfs_main_fops;
+
+ inode->i_mapping->a_ops = &sdcardfs_aops;
+
+ inode->i_atime.tv_sec = 0;
+ inode->i_atime.tv_nsec = 0;
+ inode->i_mtime.tv_sec = 0;
+ inode->i_mtime.tv_nsec = 0;
+ inode->i_ctime.tv_sec = 0;
+ inode->i_ctime.tv_nsec = 0;
+
+ /* properly initialize special inodes */
+ if (S_ISBLK(lower_inode->i_mode) || S_ISCHR(lower_inode->i_mode) ||
+ S_ISFIFO(lower_inode->i_mode) || S_ISSOCK(lower_inode->i_mode))
+ init_special_inode(inode, lower_inode->i_mode,
+ lower_inode->i_rdev);
+
+ /* all well, copy inode attributes */
+ sdcardfs_copy_and_fix_attrs(inode, lower_inode);
+ fsstack_copy_inode_size(inode, lower_inode);
+
+ unlock_new_inode(inode);
+ return inode;
+}
+
+/*
+ * Helper interpose routine, called directly by ->lookup to handle
+ * spliced dentries.
+ */
+static struct dentry *__sdcardfs_interpose(struct dentry *dentry,
+ struct super_block *sb,
+ struct path *lower_path,
+ userid_t id)
+{
+ struct inode *inode;
+ struct inode *lower_inode;
+ struct super_block *lower_sb;
+ struct dentry *ret_dentry;
+
+ lower_inode = d_inode(lower_path->dentry);
+ lower_sb = sdcardfs_lower_super(sb);
+
+ /* check that the lower file system didn't cross a mount point */
+ if (lower_inode->i_sb != lower_sb) {
+ ret_dentry = ERR_PTR(-EXDEV);
+ goto out;
+ }
+
+ /*
+ * We allocate our new inode below by calling sdcardfs_iget,
+ * which will initialize some of the new inode's fields
+ */
+
+ /* inherit lower inode number for sdcardfs's inode */
+ inode = sdcardfs_iget(sb, lower_inode, id);
+ if (IS_ERR(inode)) {
+ ret_dentry = ERR_CAST(inode);
+ goto out;
+ }
+
+ ret_dentry = d_splice_alias(inode, dentry);
+ dentry = ret_dentry ?: dentry;
+ if (!IS_ERR(dentry))
+ update_derived_permission_lock(dentry);
+out:
+ return ret_dentry;
+}
+
+/*
+ * Connect an sdcardfs inode dentry/inode with several lower ones. This is
+ * the classic stackable file system "vnode interposition" action.
+ *
+ * @dentry: sdcardfs's dentry which interposes on lower one
+ * @sb: sdcardfs's super_block
+ * @lower_path: the lower path (caller does path_get/put)
+ */
+int sdcardfs_interpose(struct dentry *dentry, struct super_block *sb,
+ struct path *lower_path, userid_t id)
+{
+ struct dentry *ret_dentry;
+
+ ret_dentry = __sdcardfs_interpose(dentry, sb, lower_path, id);
+ return PTR_ERR(ret_dentry);
+}
+
+struct sdcardfs_name_data {
+ struct dir_context ctx;
+ const struct qstr *to_find;
+ char *name;
+ bool found;
+};
+
+static int sdcardfs_name_match(struct dir_context *ctx, const char *name,
+ int namelen, loff_t offset, u64 ino, unsigned int d_type)
+{
+ struct sdcardfs_name_data *buf = container_of(ctx, struct sdcardfs_name_data, ctx);
+ struct qstr candidate = QSTR_INIT(name, namelen);
+
+ if (qstr_case_eq(buf->to_find, &candidate)) {
+ memcpy(buf->name, name, namelen);
+ buf->name[namelen] = 0;
+ buf->found = true;
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Main driver function for sdcardfs's lookup.
+ *
+ * Returns: NULL (ok), ERR_PTR if an error occurred.
+ * Fills in lower_parent_path with <dentry,mnt> on success.
+ */
+static struct dentry *__sdcardfs_lookup(struct dentry *dentry,
+ unsigned int flags, struct path *lower_parent_path, userid_t id)
+{
+ int err = 0;
+ struct vfsmount *lower_dir_mnt;
+ struct dentry *lower_dir_dentry = NULL;
+ struct dentry *lower_dentry;
+ const struct qstr *name;
+ struct path lower_path;
+ struct qstr dname;
+ struct dentry *ret_dentry = NULL;
+ struct sdcardfs_sb_info *sbi;
+
+ sbi = SDCARDFS_SB(dentry->d_sb);
+ /* must initialize dentry operations */
+ d_set_d_op(dentry, &sdcardfs_ci_dops);
+
+ if (IS_ROOT(dentry))
+ goto out;
+
+ name = &dentry->d_name;
+
+ /* now start the actual lookup procedure */
+ lower_dir_dentry = lower_parent_path->dentry;
+ lower_dir_mnt = lower_parent_path->mnt;
+
+ /* Use vfs_path_lookup to check if the dentry exists or not */
+ err = vfs_path_lookup(lower_dir_dentry, lower_dir_mnt, name->name, 0,
+ &lower_path);
+ /* check for other cases */
+ if (err == -ENOENT) {
+ struct file *file;
+ const struct cred *cred = current_cred();
+
+ struct sdcardfs_name_data buffer = {
+ .ctx.actor = sdcardfs_name_match,
+ .to_find = name,
+ .name = __getname(),
+ .found = false,
+ };
+
+ if (!buffer.name) {
+ err = -ENOMEM;
+ goto out;
+ }
+ file = dentry_open(lower_parent_path, O_RDONLY, cred);
+ if (IS_ERR(file)) {
+ err = PTR_ERR(file);
+ goto put_name;
+ }
+ err = iterate_dir(file, &buffer.ctx);
+ fput(file);
+ if (err)
+ goto put_name;
+
+ if (buffer.found)
+ err = vfs_path_lookup(lower_dir_dentry,
+ lower_dir_mnt,
+ buffer.name, 0,
+ &lower_path);
+ else
+ err = -ENOENT;
+put_name:
+ __putname(buffer.name);
+ }
+
+ /* no error: handle positive dentries */
+ if (!err) {
+ /* check if the dentry is an obb dentry
+ * if true, the lower_inode must be replaced with
+ * the inode of the graft path
+ */
+
+ if (need_graft_path(dentry)) {
+
+ /* setup_obb_dentry()
+ * The lower_path will be stored to the dentry's orig_path
+ * and the base obbpath will be copyed to the lower_path variable.
+ * if an error returned, there's no change in the lower_path
+ * returns: -ERRNO if error (0: no error)
+ */
+ err = setup_obb_dentry(dentry, &lower_path);
+
+ if (err) {
+ /* if the sbi->obbpath is not available, we can optionally
+ * setup the lower_path with its orig_path.
+ * but, the current implementation just returns an error
+ * because the sdcard daemon also regards this case as
+ * a lookup fail.
+ */
+ pr_info("sdcardfs: base obbpath is not available\n");
+ sdcardfs_put_reset_orig_path(dentry);
+ goto out;
+ }
+ }
+
+ sdcardfs_set_lower_path(dentry, &lower_path);
+ ret_dentry =
+ __sdcardfs_interpose(dentry, dentry->d_sb, &lower_path, id);
+ if (IS_ERR(ret_dentry)) {
+ err = PTR_ERR(ret_dentry);
+ /* path_put underlying path on error */
+ sdcardfs_put_reset_lower_path(dentry);
+ }
+ goto out;
+ }
+
+ /*
+ * We don't consider ENOENT an error, and we want to return a
+ * negative dentry.
+ */
+ if (err && err != -ENOENT)
+ goto out;
+
+ /* instatiate a new negative dentry */
+ dname.name = name->name;
+ dname.len = name->len;
+
+ /* See if the low-level filesystem might want
+ * to use its own hash
+ */
+ lower_dentry = d_hash_and_lookup(lower_dir_dentry, &dname);
+ if (IS_ERR(lower_dentry))
+ return lower_dentry;
+
+ if (!lower_dentry) {
+ /* We called vfs_path_lookup earlier, and did not get a negative
+ * dentry then. Don't confuse the lower filesystem by forcing
+ * one on it now...
+ */
+ err = -ENOENT;
+ goto out;
+ }
+
+ lower_path.dentry = lower_dentry;
+ lower_path.mnt = mntget(lower_dir_mnt);
+ sdcardfs_set_lower_path(dentry, &lower_path);
+
+ /*
+ * If the intent is to create a file, then don't return an error, so
+ * the VFS will continue the process of making this negative dentry
+ * into a positive one.
+ */
+ if (flags & (LOOKUP_CREATE|LOOKUP_RENAME_TARGET))
+ err = 0;
+
+out:
+ if (err)
+ return ERR_PTR(err);
+ return ret_dentry;
+}
+
+/*
+ * On success:
+ * fills dentry object appropriate values and returns NULL.
+ * On fail (== error)
+ * returns error ptr
+ *
+ * @dir : Parent inode.
+ * @dentry : Target dentry to lookup. we should set each of fields.
+ * (dentry->d_name is initialized already)
+ * @nd : nameidata of parent inode
+ */
+struct dentry *sdcardfs_lookup(struct inode *dir, struct dentry *dentry,
+ unsigned int flags)
+{
+ struct dentry *ret = NULL, *parent;
+ struct path lower_parent_path;
+ int err = 0;
+ const struct cred *saved_cred = NULL;
+
+ parent = dget_parent(dentry);
+
+ if (!check_caller_access_to_name(d_inode(parent), &dentry->d_name)) {
+ ret = ERR_PTR(-EACCES);
+ goto out_err;
+ }
+
+ /* save current_cred and override it */
+ saved_cred = override_fsids(SDCARDFS_SB(dir->i_sb),
+ SDCARDFS_I(dir)->data);
+ if (!saved_cred) {
+ ret = ERR_PTR(-ENOMEM);
+ goto out_err;
+ }
+
+ sdcardfs_get_lower_path(parent, &lower_parent_path);
+
+ /* allocate dentry private data. We free it in ->d_release */
+ err = new_dentry_private_data(dentry);
+ if (err) {
+ ret = ERR_PTR(err);
+ goto out;
+ }
+
+ ret = __sdcardfs_lookup(dentry, flags, &lower_parent_path,
+ SDCARDFS_I(dir)->data->userid);
+ if (IS_ERR(ret))
+ goto out;
+ if (ret)
+ dentry = ret;
+ if (d_inode(dentry)) {
+ fsstack_copy_attr_times(d_inode(dentry),
+ sdcardfs_lower_inode(d_inode(dentry)));
+ /* get derived permission */
+ get_derived_permission(parent, dentry);
+ fixup_tmp_permissions(d_inode(dentry));
+ fixup_lower_ownership(dentry, dentry->d_name.name);
+ }
+ /* update parent directory's atime */
+ fsstack_copy_attr_atime(d_inode(parent),
+ sdcardfs_lower_inode(d_inode(parent)));
+
+out:
+ sdcardfs_put_lower_path(parent, &lower_parent_path);
+ revert_fsids(saved_cred);
+out_err:
+ dput(parent);
+ return ret;
+}