staging: exfat: remove staging version of exfat filesystem

Now that there is a "real" solution for exfat in the vfs tree queued up
to be merged in 5.7-rc1 the "old" exfat code in staging can be removed.

Many thanks to Valdis for doing the work to get this into the tree in
the first place, it was greatly appreciated.
Acked-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: Pali Rohár <pali@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Sungjong Seo <sj1557.seo@samsung.com>
Cc: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200310105421.GA2810679@kroah.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

MAINTAINERS

@@ -6301,12 +6301,6 @@ F:	include/trace/events/mdio.h
 F:	include/uapi/linux/mdio.h
 F:	include/uapi/linux/mii.h
 
-EXFAT FILE SYSTEM
-M:	Valdis Kletnieks <valdis.kletnieks@vt.edu>
-L:	linux-fsdevel@vger.kernel.org
-S:	Maintained
-F:	drivers/staging/exfat/
-
 EXT2 FILE SYSTEM
 M:	Jan Kara <jack@suse.com>
 L:	linux-ext4@vger.kernel.org

drivers/staging/Kconfig

@@ -116,8 +116,6 @@ source "drivers/staging/fieldbus/Kconfig"
 
 source "drivers/staging/kpc2000/Kconfig"
 
-source "drivers/staging/exfat/Kconfig"
-
 source "drivers/staging/qlge/Kconfig"
 
 source "drivers/staging/hp/Kconfig"

drivers/staging/Makefile

@@ -48,7 +48,6 @@ obj-$(CONFIG_STAGING_GASKET_FRAMEWORK)	+= gasket/
 obj-$(CONFIG_XIL_AXIS_FIFO)	+= axis-fifo/
 obj-$(CONFIG_FIELDBUS_DEV)     += fieldbus/
 obj-$(CONFIG_KPC2000)		+= kpc2000/
-obj-$(CONFIG_STAGING_EXFAT_FS)	+= exfat/
 obj-$(CONFIG_QLGE)		+= qlge/
 obj-$(CONFIG_NET_VENDOR_HP)	+= hp/
 obj-$(CONFIG_WFX)		+= wfx/

drivers/staging/exfat/Kconfig

-# SPDX-License-Identifier: GPL-2.0
-config STAGING_EXFAT_FS
-	tristate "exFAT fs support"
-	depends on BLOCK
-	select NLS
-	help
-	  This adds support for the exFAT file system.
-
-config STAGING_EXFAT_DISCARD
-	bool "enable discard support"
-	depends on STAGING_EXFAT_FS
-	default y
-
-config STAGING_EXFAT_DELAYED_SYNC
-	bool "enable delayed sync"
-	depends on STAGING_EXFAT_FS
-	default n
-
-config STAGING_EXFAT_KERNEL_DEBUG
-	bool "enable kernel debug features via ioctl"
-	depends on STAGING_EXFAT_FS
-	default n
-
-config STAGING_EXFAT_DEBUG_MSG
-	bool "print debug messages"
-	depends on STAGING_EXFAT_FS
-	default n
-
-config STAGING_EXFAT_DEFAULT_CODEPAGE
-	int "Default codepage for exFAT"
-	default 437
-	depends on STAGING_EXFAT_FS
-	help
-	  This option should be set to the codepage of your exFAT filesystems.
-
-config STAGING_EXFAT_DEFAULT_IOCHARSET
-	string "Default iocharset for exFAT"
-	default "utf8"
-	depends on STAGING_EXFAT_FS
-	help
-	  Set this to the default input/output character set you'd like exFAT to use.

drivers/staging/exfat/Makefile

-# SPDX-License-Identifier: GPL-2.0-or-later
-
-obj-$(CONFIG_STAGING_EXFAT_FS) += exfat.o
-
-exfat-y :=	exfat_core.o	\
-		exfat_super.o	\
-		exfat_blkdev.o	\
-		exfat_cache.o	\
-		exfat_nls.o	\
-		exfat_upcase.o

drivers/staging/exfat/TODO

-A laundry list of things that need looking at, most of which will
-require more work than the average checkpatch cleanup...
-
-Note that some of these entries may not be bugs - they're things
-that need to be looked at, and *possibly* fixed.
-
-Clean up the ffsCamelCase function names.
-
-Fix (thing)->flags to not use magic numbers - multiple offenders
-
-Sort out all the s32/u32/u8 nonsense - most of these should be plain int.
-
-exfat_core.c - ffsReadFile - the goto err_out seem to leak a brelse().
-same for ffsWriteFile.
-
-All the calls to fs_sync() need to be looked at, particularly in the
-context of EXFAT_DELAYED_SYNC. Currently, if that's defined, we only
-flush to disk when sync() gets called.  We should be doing at least
-metadata flushes at appropriate times.
-
-ffsTruncateFile -  if (old_size <= new_size) {
-That doesn't look right. How did it ever work? Are they relying on lazy
-block allocation when actual writes happen? If nothing else, it never
-does the 'fid->size = new_size' and do the inode update....
-
-ffsSetAttr() is just dangling in the breeze, not wired up at all...
-
-Convert global mutexes to a per-superblock mutex.
-
-Right now, we load exactly one UTF-8 table. Check to see
-if that plays nice with different codepage and iocharset values
-for simultanous mounts of different devices
-
-exfat_rmdir() checks for -EBUSY but ffsRemoveDir() doesn't return it.
-In fact, there's a complete lack of -EBUSY testing anywhere.
-
-There's probably a few missing checks for -EEXIST
-
-check return codes of sync_dirty_buffer()
-
-Why is remove_file doing a num_entries++??
-
-Double check a lot of can't-happen parameter checks (for null pointers for
-things that have only one call site and can't pass a null, etc).
-
-All the DEBUG stuff can probably be tossed, including the ioctl(). Either
-that, or convert to a proper fault-injection system.
-
-exfat_remount does exactly one thing.  Fix to actually deal with remount
-options, particularly handling R/O correctly.  For that matter, allow
-R/O mounts in the first place.
-
-Figure out why the VFAT code used multi_sector_(read|write) but the
-exfat code doesn't use it. The difference matters on SSDs with wear leveling.
-
-exfat_fat_sync(), exfat_buf_sync(), and sync_alloc_bitmap()
-aren't called anyplace....
-
-Create helper function for exfat_set_entry_time() and exfat_set_entry_type()
-because it's sort of ugly to be calling the same functionn directly and
-other code calling through the fs_func struc ponters...
-
-clean up the remaining vol_type checks, which are of two types:
-some are ?: operators with magic numbers, and the rest are places
-where we're doing stuff with '.' and '..'.
-
-Patches to:
-	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-	Valdis Kletnieks <valdis.kletnieks@vt.edu>

drivers/staging/exfat/exfat_blkdev.c

-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- *  Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
- */
-
-#include <linux/blkdev.h>
-#include <linux/buffer_head.h>
-#include <linux/fs.h>
-#include "exfat.h"
-
-void exfat_bdev_open(struct super_block *sb)
-{
-	struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-
-	if (p_bd->opened)
-		return;
-
-	p_bd->sector_size      = bdev_logical_block_size(sb->s_bdev);
-	p_bd->sector_size_bits = ilog2(p_bd->sector_size);
-	p_bd->sector_size_mask = p_bd->sector_size - 1;
-	p_bd->num_sectors      = i_size_read(sb->s_bdev->bd_inode) >>
-				 p_bd->sector_size_bits;
-	p_bd->opened = true;
-}
-
-void exfat_bdev_close(struct super_block *sb)
-{
-	struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-
-	p_bd->opened = false;
-}
-
-int exfat_bdev_read(struct super_block *sb, sector_t secno,
-		    struct buffer_head **bh, u32 num_secs,
-		    bool read)
-{
-	struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-	struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
-#ifdef CONFIG_STAGING_EXFAT_KERNEL_DEBUG
-	struct exfat_sb_info *sbi = EXFAT_SB(sb);
-	long flags = sbi->debug_flags;
-
-	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return -EIO;
-#endif /* CONFIG_STAGING_EXFAT_KERNEL_DEBUG */
-
-	if (!p_bd->opened)
-		return -ENODEV;
-
-	if (*bh)
-		__brelse(*bh);
-
-	if (read)
-		*bh = __bread(sb->s_bdev, secno,
-			      num_secs << p_bd->sector_size_bits);
-	else
-		*bh = __getblk(sb->s_bdev, secno,
-			       num_secs << p_bd->sector_size_bits);
-
-	if (*bh)
-		return 0;
-
-	WARN(!p_fs->dev_ejected,
-	     "[EXFAT] No bh, device seems wrong or to be ejected.\n");
-
-	return -EIO;
-}
-
-int exfat_bdev_write(struct super_block *sb, sector_t secno,
-		     struct buffer_head *bh,
-		     u32 num_secs, bool sync)
-{
-	s32 count;
-	struct buffer_head *bh2;
-	struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-	struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
-#ifdef CONFIG_STAGING_EXFAT_KERNEL_DEBUG
-	struct exfat_sb_info *sbi = EXFAT_SB(sb);
-	long flags = sbi->debug_flags;
-
-	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return -EIO;
-#endif /* CONFIG_STAGING_EXFAT_KERNEL_DEBUG */
-
-	if (!p_bd->opened)
-		return -ENODEV;
-
-	if (secno == bh->b_blocknr) {
-		lock_buffer(bh);
-		set_buffer_uptodate(bh);
-		mark_buffer_dirty(bh);
-		unlock_buffer(bh);
-		if (sync && (sync_dirty_buffer(bh) != 0))
-			return -EIO;
-	} else {
-		count = num_secs << p_bd->sector_size_bits;
-
-		bh2 = __getblk(sb->s_bdev, secno, count);
-		if (!bh2)
-			goto no_bh;
-
-		lock_buffer(bh2);
-		memcpy(bh2->b_data, bh->b_data, count);
-		set_buffer_uptodate(bh2);
-		mark_buffer_dirty(bh2);
-		unlock_buffer(bh2);
-		if (sync && (sync_dirty_buffer(bh2) != 0)) {
-			__brelse(bh2);
-			goto no_bh;
-		}
-		__brelse(bh2);
-	}
-
-	return 0;
-
-no_bh:
-	WARN(!p_fs->dev_ejected,
-	     "[EXFAT] No bh, device seems wrong or to be ejected.\n");
-
-	return -EIO;
-}
-
-int exfat_bdev_sync(struct super_block *sb)
-{
-	struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
-#ifdef CONFIG_STAGING_EXFAT_KERNEL_DEBUG
-	struct exfat_sb_info *sbi = EXFAT_SB(sb);
-	long flags = sbi->debug_flags;
-
-	if (flags & EXFAT_DEBUGFLAGS_ERROR_RW)
-		return -EIO;
-#endif /* CONFIG_STAGING_EXFAT_KERNEL_DEBUG */
-
-	if (!p_bd->opened)
-		return -ENODEV;
-
-	return sync_blockdev(sb->s_bdev);
-}

drivers/staging/exfat/exfat_nls.c

-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- *  Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
- */
-
-#include <linux/string.h>
-#include <linux/nls.h>
-#include "exfat.h"
-
-static u16 bad_uni_chars[] = {
-	/* " * / : < > ? \ | */
-	0x0022,         0x002A, 0x002F, 0x003A,
-	0x003C, 0x003E, 0x003F, 0x005C, 0x007C,
-	0
-};
-
-static int convert_ch_to_uni(struct nls_table *nls, u16 *uni, u8 *ch,
-			     bool *lossy)
-{
-	int len;
-
-	*uni = 0x0;
-
-	if (ch[0] < 0x80) {
-		*uni = (u16)ch[0];
-		return 1;
-	}
-
-	len = nls->char2uni(ch, NLS_MAX_CHARSET_SIZE, uni);
-	if (len < 0) {
-		/* conversion failed */
-		pr_info("%s: fail to use nls\n", __func__);
-		if (lossy)
-			*lossy = true;
-		*uni = (u16)'_';
-		if (!strcmp(nls->charset, "utf8"))
-			return 1;
-		else
-			return 2;
-	}
-
-	return len;
-}
-
-static int convert_uni_to_ch(struct nls_table *nls, u8 *ch, u16 uni,
-			     bool *lossy)
-{
-	int len;
-
-	ch[0] = 0x0;
-
-	if (uni < 0x0080) {
-		ch[0] = (u8)uni;
-		return 1;
-	}
-
-	len = nls->uni2char(uni, ch, NLS_MAX_CHARSET_SIZE);
-	if (len < 0) {
-		/* conversion failed */
-		pr_info("%s: fail to use nls\n", __func__);
-		if (lossy)
-			*lossy = true;
-		ch[0] = '_';
-		return 1;
-	}
-
-	return len;
-}
-
-u16 nls_upper(struct super_block *sb, u16 a)
-{
-	struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
-
-	if (EXFAT_SB(sb)->options.casesensitive)
-		return a;
-	if (p_fs->vol_utbl && p_fs->vol_utbl[get_col_index(a)])
-		return p_fs->vol_utbl[get_col_index(a)][get_row_index(a)];
-	else
-		return a;
-}
-
-static u16 *nls_wstrchr(u16 *str, u16 wchar)
-{
-	while (*str) {
-		if (*(str++) == wchar)
-			return str;
-	}
-
-	return NULL;
-}
-
-int nls_uniname_cmp(struct super_block *sb, u16 *a, u16 *b)
-{
-	int i;
-
-	for (i = 0; i < MAX_NAME_LENGTH; i++, a++, b++) {
-		if (nls_upper(sb, *a) != nls_upper(sb, *b))
-			return 1;
-		if (*a == 0x0)
-			return 0;
-	}
-	return 0;
-}
-
-void nls_uniname_to_cstring(struct super_block *sb, u8 *p_cstring,
-			    struct uni_name_t *p_uniname)
-{
-	int i, j, len;
-	u8 buf[MAX_CHARSET_SIZE];
-	u16 *uniname = p_uniname->name;
-	struct nls_table *nls = EXFAT_SB(sb)->nls_io;
-
-	if (!nls) {
-		len = utf16s_to_utf8s(uniname, MAX_NAME_LENGTH,
-				      UTF16_HOST_ENDIAN, p_cstring,
-				      MAX_NAME_LENGTH);
-		p_cstring[len] = 0;
-		return;
-	}
-
-	i = 0;
-	while (i < (MAX_NAME_LENGTH - 1)) {
-		if (*uniname == (u16)'\0')
-			break;
-
-		len = convert_uni_to_ch(nls, buf, *uniname, NULL);
-
-		if (len > 1) {
-			for (j = 0; j < len; j++)
-				*p_cstring++ = (char)*(buf + j);
-		} else { /* len == 1 */
-			*p_cstring++ = (char)*buf;
-		}
-
-		uniname++;
-		i++;
-	}
-
-	*p_cstring = '\0';
-}
-
-void nls_cstring_to_uniname(struct super_block *sb,
-			    struct uni_name_t *p_uniname, u8 *p_cstring,
-			    bool *p_lossy)
-{
-	int i, j;
-	bool lossy = false;
-	u8 *end_of_name;
-	u8 upname[MAX_NAME_LENGTH * 2];
-	u16 *uniname = p_uniname->name;
-	struct nls_table *nls = EXFAT_SB(sb)->nls_io;
-
-	/* strip all trailing spaces */
-	end_of_name = p_cstring + strlen(p_cstring);
-
-	while (*(--end_of_name) == ' ') {
-		if (end_of_name < p_cstring)
-			break;
-	}
-	*(++end_of_name) = '\0';
-
-	if (strcmp(p_cstring, ".") && strcmp(p_cstring, "..")) {
-		/* strip all trailing periods */
-		while (*(--end_of_name) == '.') {
-			if (end_of_name < p_cstring)
-				break;
-		}
-		*(++end_of_name) = '\0';
-	}
-
-	if (*p_cstring == '\0')
-		lossy = true;
-
-	if (!nls) {
-		i = utf8s_to_utf16s(p_cstring, MAX_NAME_LENGTH,
-				    UTF16_HOST_ENDIAN, uniname,
-				    MAX_NAME_LENGTH);
-		for (j = 0; j < i; j++)
-			SET16_A(upname + j * 2, nls_upper(sb, uniname[j]));
-		uniname[i] = '\0';
-	} else {
-		i = 0;
-		j = 0;
-		while (j < (MAX_NAME_LENGTH - 1)) {
-			if (*(p_cstring + i) == '\0')
-				break;
-
-			i += convert_ch_to_uni(nls, uniname,
-					       (u8 *)(p_cstring + i), &lossy);
-
-			if ((*uniname < 0x0020) ||
-			    nls_wstrchr(bad_uni_chars, *uniname))
-				lossy = true;
-
-			SET16_A(upname + j * 2, nls_upper(sb, *uniname));
-
-			uniname++;
-			j++;
-		}
-
-		if (*(p_cstring + i) != '\0')
-			lossy = true;
-		*uniname = (u16)'\0';
-	}
-
-	p_uniname->name_len = j;
-	p_uniname->name_hash = calc_checksum_2byte(upname, j << 1, 0,
-						   CS_DEFAULT);
-
-	if (p_lossy)
-		*p_lossy = lossy;
-}