[ALPS05914317] SDCARDFS: add back

We add back sdcardfs in 4.19 due to OTA and some legacy
apks of MTK:
 - uxjack apk needs to use FUSE APIs
 - avoid case-insensitive filename feature effect

MTK-Commit-Id: 265ee40dcc2b49bf804fc4d701576fb6d447181b

Change-Id: I07cce3588e51118f402a2a306fe05c322c1b61a6
Signed-off-by: Peng Zhou <[email protected]>
CR-Id: ALPS05914317
Feature: [Android Default] Sdcard File System

drivers/misc/mediatek/Kconfig.default

@@ -215,6 +215,7 @@ config ANDROID_DEFAULT_SETTING
 	select QUOTACTL
 	select RTC_CLASS
 	select SCHED_DEBUG
+	select SDCARD_FS
 	select SECCOMP
 	select SECCOMP_FILTER
 	select SECURITY

fs/Kconfig

@@ -237,6 +237,7 @@ source "fs/orangefs/Kconfig"
 source "fs/adfs/Kconfig"
 source "fs/affs/Kconfig"
 source "fs/ecryptfs/Kconfig"
+source "fs/sdcardfs/Kconfig"
 source "fs/hfs/Kconfig"
 source "fs/hfsplus/Kconfig"
 source "fs/befs/Kconfig"

fs/Makefile

@@ -85,6 +85,7 @@ obj-$(CONFIG_ISO9660_FS)	+= isofs/
 obj-$(CONFIG_HFSPLUS_FS)	+= hfsplus/ # Before hfs to find wrapped HFS+
 obj-$(CONFIG_HFS_FS)		+= hfs/
 obj-$(CONFIG_ECRYPT_FS)		+= ecryptfs/
+obj-$(CONFIG_SDCARD_FS)		+= sdcardfs/
 obj-$(CONFIG_VXFS_FS)		+= freevxfs/
 obj-$(CONFIG_NFS_FS)		+= nfs/
 obj-$(CONFIG_EXPORTFS)		+= exportfs/

fs/attr.c

@@ -223,7 +223,7 @@ EXPORT_SYMBOL(setattr_copy);
  * the file open for write, as there can be no conflicting delegation in
  * that case.
  */
-int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
+int notify_change2(struct vfsmount *mnt, struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
 {
 	struct inode *inode = dentry->d_inode;
 	umode_t mode = inode->i_mode;
@@ -247,7 +247,7 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 			return -EPERM;
 
 		if (!inode_owner_or_capable(inode)) {
-			error = inode_permission(inode, MAY_WRITE);
+			error = inode_permission2(mnt, inode, MAY_WRITE);
 			if (error)
 				return error;
 		}
@@ -330,7 +330,9 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 	if (error)
 		return error;
 
-	if (inode->i_op->setattr)
+	if (mnt && inode->i_op->setattr2)
+		error = inode->i_op->setattr2(mnt, dentry, attr);
+	else if (inode->i_op->setattr)
 		error = inode->i_op->setattr(dentry, attr);
 	else
 		error = simple_setattr(dentry, attr);
@@ -343,4 +345,10 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 
 	return error;
 }
+EXPORT_SYMBOL_GPL(notify_change2);
+
+int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
+{
+	return notify_change2(NULL, dentry, attr, delegated_inode);
+}
 EXPORT_SYMBOL(notify_change);

fs/coredump.c

@@ -806,7 +806,7 @@ void do_coredump(const siginfo_t *siginfo)
 			goto close_fail;
 		if (!(cprm.file->f_mode & FMODE_CAN_WRITE))
 			goto close_fail;
-		if (do_truncate(cprm.file->f_path.dentry, 0, 0, cprm.file))
+		if (do_truncate2(cprm.file->f_path.mnt, cprm.file->f_path.dentry, 0, 0, cprm.file))
 			goto close_fail;
 	}
 

fs/crypto/keyring.c

@@ -867,12 +867,34 @@ static int check_for_busy_inodes(struct super_block *sb,
 	return -EBUSY;
 }
 
+static BLOCKING_NOTIFIER_HEAD(fscrypt_key_removal_notifiers);
+
+/*
+ * Register a function to be executed when the FS_IOC_REMOVE_ENCRYPTION_KEY
+ * ioctl has removed a key and is about to try evicting inodes.
+ */
+int fscrypt_register_key_removal_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&fscrypt_key_removal_notifiers,
+						nb);
+}
+EXPORT_SYMBOL_GPL(fscrypt_register_key_removal_notifier);
+
+int fscrypt_unregister_key_removal_notifier(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&fscrypt_key_removal_notifiers,
+						  nb);
+}
+EXPORT_SYMBOL_GPL(fscrypt_unregister_key_removal_notifier);
+
 static int try_to_lock_encrypted_files(struct super_block *sb,
 				       struct fscrypt_master_key *mk)
 {
 	int err1;
 	int err2;
 
+	blocking_notifier_call_chain(&fscrypt_key_removal_notifiers, 0, NULL);
+
 	/*
 	 * An inode can't be evicted while it is dirty or has dirty pages.
 	 * Thus, we first have to clean the inodes in ->mk_decrypted_inodes.

fs/exec.c

@@ -1324,7 +1324,7 @@ EXPORT_SYMBOL(flush_old_exec);
 void would_dump(struct linux_binprm *bprm, struct file *file)
 {
 	struct inode *inode = file_inode(file);
-	if (inode_permission(inode, MAY_READ) < 0) {
+	if (inode_permission2(file->f_path.mnt, inode, MAY_READ) < 0) {
 		struct user_namespace *old, *user_ns;
 		bprm->interp_flags |= BINPRM_FLAGS_ENFORCE_NONDUMP;
 

fs/inode.c

@@ -1803,7 +1803,7 @@ int dentry_needs_remove_privs(struct dentry *dentry)
 	return mask;
 }
 
-static int __remove_privs(struct dentry *dentry, int kill)
+static int __remove_privs(struct vfsmount *mnt, struct dentry *dentry, int kill)
 {
 	struct iattr newattrs;
 
@@ -1812,7 +1812,7 @@ static int __remove_privs(struct dentry *dentry, int kill)
 	 * Note we call this on write, so notify_change will not
 	 * encounter any conflicting delegations:
 	 */
-	return notify_change(dentry, &newattrs, NULL);
+	return notify_change2(mnt, dentry, &newattrs, NULL);
 }
 
 /*
@@ -1839,7 +1839,7 @@ int file_remove_privs(struct file *file)
 	if (kill < 0)
 		return kill;
 	if (kill)
-		error = __remove_privs(dentry, kill);
+		error = __remove_privs(file->f_path.mnt, dentry, kill);
 	if (!error)
 		inode_has_no_xattr(inode);