ext4: Add fs parameter specifications for mount options

Create an array of fs_parameter_spec called ext4_param_specs to
hold the mount option specifications we're going to be using with the
new mount api.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Link: https://lore.kernel.org/r/20211027141857.33657-3-lczerner@redhat.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/super.c

@@ -47,6 +47,8 @@
 #include <linux/kthread.h>
 #include <linux/freezer.h>
 #include <linux/fsnotify.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
 
 #include "ext4.h"
 #include "ext4_extents.h"	/* Needed for trace points definition */
@@ -1688,11 +1690,160 @@ enum {
 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
 	Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
+	Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
 #ifdef CONFIG_EXT4_DEBUG
 	Opt_fc_debug_max_replay, Opt_fc_debug_force
 #endif
 };
 
+static const struct constant_table ext4_param_errors[] = {
+	{"continue",	Opt_err_cont},
+	{"panic",	Opt_err_panic},
+	{"remount-ro",	Opt_err_ro},
+	{}
+};
+
+static const struct constant_table ext4_param_data[] = {
+	{"journal",	Opt_data_journal},
+	{"ordered",	Opt_data_ordered},
+	{"writeback",	Opt_data_writeback},
+	{}
+};
+
+static const struct constant_table ext4_param_data_err[] = {
+	{"abort",	Opt_data_err_abort},
+	{"ignore",	Opt_data_err_ignore},
+	{}
+};
+
+static const struct constant_table ext4_param_jqfmt[] = {
+	{"vfsold",	Opt_jqfmt_vfsold},
+	{"vfsv0",	Opt_jqfmt_vfsv0},
+	{"vfsv1",	Opt_jqfmt_vfsv1},
+	{}
+};
+
+static const struct constant_table ext4_param_dax[] = {
+	{"always",	Opt_dax_always},
+	{"inode",	Opt_dax_inode},
+	{"never",	Opt_dax_never},
+	{}
+};
+
+/* String parameter that allows empty argument */
+#define fsparam_string_empty(NAME, OPT) \
+	__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
+
+/*
+ * Mount option specification
+ * We don't use fsparam_flag_no because of the way we set the
+ * options and the way we show them in _ext4_show_options(). To
+ * keep the changes to a minimum, let's keep the negative options
+ * separate for now.
+ */
+static const struct fs_parameter_spec ext4_param_specs[] = {
+	fsparam_flag	("bsddf",		Opt_bsd_df),
+	fsparam_flag	("minixdf",		Opt_minix_df),
+	fsparam_flag	("grpid",		Opt_grpid),
+	fsparam_flag	("bsdgroups",		Opt_grpid),
+	fsparam_flag	("nogrpid",		Opt_nogrpid),
+	fsparam_flag	("sysvgroups",		Opt_nogrpid),
+	fsparam_u32	("resgid",		Opt_resgid),
+	fsparam_u32	("resuid",		Opt_resuid),
+	fsparam_u32	("sb",			Opt_sb),
+	fsparam_enum	("errors",		Opt_errors, ext4_param_errors),
+	fsparam_flag	("nouid32",		Opt_nouid32),
+	fsparam_flag	("debug",		Opt_debug),
+	fsparam_flag	("oldalloc",		Opt_removed),
+	fsparam_flag	("orlov",		Opt_removed),
+	fsparam_flag	("user_xattr",		Opt_user_xattr),
+	fsparam_flag	("nouser_xattr",	Opt_nouser_xattr),
+	fsparam_flag	("acl",			Opt_acl),
+	fsparam_flag	("noacl",		Opt_noacl),
+	fsparam_flag	("norecovery",		Opt_noload),
+	fsparam_flag	("noload",		Opt_noload),
+	fsparam_flag	("bh",			Opt_removed),
+	fsparam_flag	("nobh",		Opt_removed),
+	fsparam_u32	("commit",		Opt_commit),
+	fsparam_u32	("min_batch_time",	Opt_min_batch_time),
+	fsparam_u32	("max_batch_time",	Opt_max_batch_time),
+	fsparam_u32	("journal_dev",		Opt_journal_dev),
+	fsparam_bdev	("journal_path",	Opt_journal_path),
+	fsparam_flag	("journal_checksum",	Opt_journal_checksum),
+	fsparam_flag	("nojournal_checksum",	Opt_nojournal_checksum),
+	fsparam_flag	("journal_async_commit",Opt_journal_async_commit),
+	fsparam_flag	("abort",		Opt_abort),
+	fsparam_enum	("data",		Opt_data, ext4_param_data),
+	fsparam_enum	("data_err",		Opt_data_err,
+						ext4_param_data_err),
+	fsparam_string_empty
+			("usrjquota",		Opt_usrjquota),
+	fsparam_string_empty
+			("grpjquota",		Opt_grpjquota),
+	fsparam_enum	("jqfmt",		Opt_jqfmt, ext4_param_jqfmt),
+	fsparam_flag	("grpquota",		Opt_grpquota),
+	fsparam_flag	("quota",		Opt_quota),
+	fsparam_flag	("noquota",		Opt_noquota),
+	fsparam_flag	("usrquota",		Opt_usrquota),
+	fsparam_flag	("prjquota",		Opt_prjquota),
+	fsparam_flag	("barrier",		Opt_barrier),
+	fsparam_u32	("barrier",		Opt_barrier),
+	fsparam_flag	("nobarrier",		Opt_nobarrier),
+	fsparam_flag	("i_version",		Opt_i_version),
+	fsparam_flag	("dax",			Opt_dax),
+	fsparam_enum	("dax",			Opt_dax_type, ext4_param_dax),
+	fsparam_u32	("stripe",		Opt_stripe),
+	fsparam_flag	("delalloc",		Opt_delalloc),
+	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
+	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
+	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
+	fsparam_flag	("lazytime",		Opt_lazytime),
+	fsparam_flag	("nolazytime",		Opt_nolazytime),
+	fsparam_u32	("debug_want_extra_isize",
+						Opt_debug_want_extra_isize),
+	fsparam_flag	("mblk_io_submit",	Opt_removed),
+	fsparam_flag	("nomblk_io_submit",	Opt_removed),
+	fsparam_flag	("block_validity",	Opt_block_validity),
+	fsparam_flag	("noblock_validity",	Opt_noblock_validity),
+	fsparam_u32	("inode_readahead_blks",
+						Opt_inode_readahead_blks),
+	fsparam_u32	("journal_ioprio",	Opt_journal_ioprio),
+	fsparam_u32	("auto_da_alloc",	Opt_auto_da_alloc),
+	fsparam_flag	("auto_da_alloc",	Opt_auto_da_alloc),
+	fsparam_flag	("noauto_da_alloc",	Opt_noauto_da_alloc),
+	fsparam_flag	("dioread_nolock",	Opt_dioread_nolock),
+	fsparam_flag	("nodioread_nolock",	Opt_dioread_lock),
+	fsparam_flag	("dioread_lock",	Opt_dioread_lock),
+	fsparam_flag	("discard",		Opt_discard),
+	fsparam_flag	("nodiscard",		Opt_nodiscard),
+	fsparam_u32	("init_itable",		Opt_init_itable),
+	fsparam_flag	("init_itable",		Opt_init_itable),
+	fsparam_flag	("noinit_itable",	Opt_noinit_itable),
+#ifdef CONFIG_EXT4_DEBUG
+	fsparam_flag	("fc_debug_force",	Opt_fc_debug_force),
+	fsparam_u32	("fc_debug_max_replay",	Opt_fc_debug_max_replay),
+#endif
+	fsparam_u32	("max_dir_size_kb",	Opt_max_dir_size_kb),
+	fsparam_flag	("test_dummy_encryption",
+						Opt_test_dummy_encryption),
+	fsparam_string	("test_dummy_encryption",
+						Opt_test_dummy_encryption),
+	fsparam_flag	("inlinecrypt",		Opt_inlinecrypt),
+	fsparam_flag	("nombcache",		Opt_nombcache),
+	fsparam_flag	("no_mbcache",		Opt_nombcache),	/* for backward compatibility */
+	fsparam_flag	("prefetch_block_bitmaps",
+						Opt_removed),
+	fsparam_flag	("no_prefetch_block_bitmaps",
+						Opt_no_prefetch_block_bitmaps),
+	fsparam_s32	("mb_optimize_scan",	Opt_mb_optimize_scan),
+	fsparam_string	("check",		Opt_removed),	/* mount option from ext2/3 */
+	fsparam_flag	("nocheck",		Opt_removed),	/* mount option from ext2/3 */
+	fsparam_flag	("reservation",		Opt_removed),	/* mount option from ext2/3 */
+	fsparam_flag	("noreservation",	Opt_removed),	/* mount option from ext2/3 */
+	fsparam_u32	("journal",		Opt_removed),	/* mount option from ext2/3 */
+	{}
+};
+
 static const match_table_t tokens = {
 	{Opt_bsd_df, "bsddf"},
 	{Opt_minix_df, "minixdf"},