summaryrefslogtreecommitdiffstats
path: root/drivers/char/ftape/lowlevel/ftape-bsm.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/char/ftape/lowlevel/ftape-bsm.c')
-rw-r--r--drivers/char/ftape/lowlevel/ftape-bsm.c491
1 files changed, 491 insertions, 0 deletions
diff --git a/drivers/char/ftape/lowlevel/ftape-bsm.c b/drivers/char/ftape/lowlevel/ftape-bsm.c
new file mode 100644
index 00000000000..d1a301cc344
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-bsm.c
@@ -0,0 +1,491 @@
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven,
+ * (C) 1996-1997 Claus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING. If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-bsm.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/05 19:15:15 $
+ *
+ * This file contains the bad-sector map handling code for
+ * the QIC-117 floppy tape driver for Linux.
+ * QIC-40, QIC-80, QIC-3010 and QIC-3020 maps are implemented.
+ */
+
+#include <linux/string.h>
+
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+
+/* Global vars.
+ */
+
+/* Local vars.
+ */
+static __u8 *bad_sector_map;
+static SectorCount *bsm_hash_ptr;
+
+typedef enum {
+ forward, backward
+} mode_type;
+
+#if 0
+static void ftape_put_bad_sector_entry(int segment_id, SectorMap new_map);
+#endif
+
+#if 0
+/* fix_tape converts a normal QIC-80 tape into a 'wide' tape.
+ * For testing purposes only !
+ */
+void fix_tape(__u8 * buffer, ft_format_type new_code)
+{
+ static __u8 list[BAD_SECTOR_MAP_SIZE];
+ SectorMap *src_ptr = (SectorMap *) list;
+ __u8 *dst_ptr = bad_sector_map;
+ SectorMap map;
+ unsigned int sector = 1;
+ int i;
+
+ if (format_code != fmt_var && format_code != fmt_big) {
+ memcpy(list, bad_sector_map, sizeof(list));
+ memset(bad_sector_map, 0, sizeof(bad_sector_map));
+ while ((__u8 *) src_ptr - list < sizeof(list)) {
+ map = *src_ptr++;
+ if (map == EMPTY_SEGMENT) {
+ *(SectorMap *) dst_ptr = 0x800000 + sector;
+ dst_ptr += 3;
+ sector += SECTORS_PER_SEGMENT;
+ } else {
+ for (i = 0; i < SECTORS_PER_SEGMENT; ++i) {
+ if (map & 1) {
+ *(SewctorMap *) dst_ptr = sector;
+ dst_ptr += 3;
+ }
+ map >>= 1;
+ ++sector;
+ }
+ }
+ }
+ }
+ bad_sector_map_changed = 1;
+ *(buffer + 4) = new_code; /* put new format code */
+ if (format_code != fmt_var && new_code == fmt_big) {
+ PUT4(buffer, FT_6_HSEG_1, (__u32)GET2(buffer, 6));
+ PUT4(buffer, FT_6_HSEG_2, (__u32)GET2(buffer, 8));
+ PUT4(buffer, FT_6_FRST_SEG, (__u32)GET2(buffer, 10));
+ PUT4(buffer, FT_6_LAST_SEG, (__u32)GET2(buffer, 12));
+ memset(buffer+6, '\0', 8);
+ }
+ format_code = new_code;
+}
+
+#endif
+
+/* given buffer that contains a header segment, find the end of
+ * of the bsm list
+ */
+__u8 * ftape_find_end_of_bsm_list(__u8 * address)
+{
+ __u8 *ptr = address + FT_HEADER_END; /* start of bsm list */
+ __u8 *limit = address + FT_SEGMENT_SIZE;
+ while (ptr + 2 < limit) {
+ if (ptr[0] || ptr[1] || ptr[2]) {
+ ptr += 3;
+ } else {
+ return ptr;
+ }
+ }
+ return NULL;
+}
+
+static inline void put_sector(SectorCount *ptr, unsigned int sector)
+{
+ ptr->bytes[0] = sector & 0xff;
+ sector >>= 8;
+ ptr->bytes[1] = sector & 0xff;
+ sector >>= 8;
+ ptr->bytes[2] = sector & 0xff;
+}
+
+static inline unsigned int get_sector(SectorCount *ptr)
+{
+#if 1
+ unsigned int sector;
+
+ sector = ptr->bytes[0];
+ sector += ptr->bytes[1] << 8;
+ sector += ptr->bytes[2] << 16;
+
+ return sector;
+#else
+ /* GET4 gets the next four bytes in Intel little endian order
+ * and converts them to host byte order and handles unaligned
+ * access.
+ */
+ return (GET4(ptr, 0) & 0x00ffffff); /* back to host byte order */
+#endif
+}
+
+static void bsm_debug_fake(void)
+{
+ /* for testing of bad sector handling at end of tape
+ */
+#if 0
+ ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 3,
+ 0x000003e0;
+ ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 2,
+ 0xff3fffff;
+ ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 1,
+ 0xffffe000;
+#endif
+ /* Enable to test bad sector handling
+ */
+#if 0
+ ftape_put_bad_sector_entry(30, 0xfffffffe)
+ ftape_put_bad_sector_entry(32, 0x7fffffff);
+ ftape_put_bad_sector_entry(34, 0xfffeffff);
+ ftape_put_bad_sector_entry(36, 0x55555555);
+ ftape_put_bad_sector_entry(38, 0xffffffff);
+ ftape_put_bad_sector_entry(50, 0xffff0000);
+ ftape_put_bad_sector_entry(51, 0xffffffff);
+ ftape_put_bad_sector_entry(52, 0xffffffff);
+ ftape_put_bad_sector_entry(53, 0x0000ffff);
+#endif
+ /* Enable when testing multiple volume tar dumps.
+ */
+#if 0
+ {
+ int i;
+
+ for (i = ft_first_data_segment;
+ i <= ft_last_data_segment - 7; ++i) {
+ ftape_put_bad_sector_entry(i, EMPTY_SEGMENT);
+ }
+ }
+#endif
+ /* Enable when testing bit positions in *_error_map
+ */
+#if 0
+ {
+ int i;
+
+ for (i = first_data_segment; i <= last_data_segment; ++i) {
+ ftape_put_bad_sector_entry(i,
+ ftape_get_bad_sector_entry(i)
+ | 0x00ff00ff);
+ }
+ }
+#endif
+}
+
+static void print_bad_sector_map(void)
+{
+ unsigned int good_sectors;
+ unsigned int total_bad = 0;
+ int i;
+ TRACE_FUN(ft_t_flow);
+
+ if (ft_format_code == fmt_big ||
+ ft_format_code == fmt_var ||
+ ft_format_code == fmt_1100ft) {
+ SectorCount *ptr = (SectorCount *)bad_sector_map;
+ unsigned int sector;
+ __u16 *ptr16;
+
+ while((sector = get_sector(ptr++)) != 0) {
+ if ((ft_format_code == fmt_big ||
+ ft_format_code == fmt_var) &&
+ sector & 0x800000) {
+ total_bad += FT_SECTORS_PER_SEGMENT - 3;
+ TRACE(ft_t_noise, "bad segment at sector: %6d",
+ sector & 0x7fffff);
+ } else {
+ ++total_bad;
+ TRACE(ft_t_noise, "bad sector: %6d", sector);
+ }
+ }
+ /* Display old ftape's end-of-file marks
+ */
+ ptr16 = (__u16*)ptr;
+ while ((sector = get_unaligned(ptr16++)) != 0) {
+ TRACE(ft_t_noise, "Old ftape eof mark: %4d/%2d",
+ sector, get_unaligned(ptr16++));
+ }
+ } else { /* fixed size format */
+ for (i = ft_first_data_segment;
+ i < (int)(ft_segments_per_track * ft_tracks_per_tape); ++i) {
+ SectorMap map = ((SectorMap *) bad_sector_map)[i];
+
+ if (map) {
+ TRACE(ft_t_noise,
+ "bsm for segment %4d: 0x%08x", i, (unsigned int)map);
+ total_bad += ((map == EMPTY_SEGMENT)
+ ? FT_SECTORS_PER_SEGMENT - 3
+ : count_ones(map));
+ }
+ }
+ }
+ good_sectors =
+ ((ft_segments_per_track * ft_tracks_per_tape - ft_first_data_segment)
+ * (FT_SECTORS_PER_SEGMENT - 3)) - total_bad;
+ TRACE(ft_t_info, "%d Kb usable on this tape", good_sectors);
+ if (total_bad == 0) {
+ TRACE(ft_t_info,
+ "WARNING: this tape has no bad blocks registered !");
+ } else {
+ TRACE(ft_t_info, "%d bad sectors", total_bad);
+ }
+ TRACE_EXIT;
+}
+
+
+void ftape_extract_bad_sector_map(__u8 * buffer)
+{
+ TRACE_FUN(ft_t_any);
+
+ /* Fill the bad sector map with the contents of buffer.
+ */
+ if (ft_format_code == fmt_var || ft_format_code == fmt_big) {
+ /* QIC-3010/3020 and wide QIC-80 tapes no longer have a failed
+ * sector log but use this area to extend the bad sector map.
+ */
+ bad_sector_map = &buffer[FT_HEADER_END];
+ } else {
+ /* non-wide QIC-80 tapes have a failed sector log area that
+ * mustn't be included in the bad sector map.
+ */
+ bad_sector_map = &buffer[FT_FSL + FT_FSL_SIZE];
+ }
+ if (ft_format_code == fmt_1100ft ||
+ ft_format_code == fmt_var ||
+ ft_format_code == fmt_big) {
+ bsm_hash_ptr = (SectorCount *)bad_sector_map;
+ } else {
+ bsm_hash_ptr = NULL;
+ }
+ bsm_debug_fake();
+ if (TRACE_LEVEL >= ft_t_info) {
+ print_bad_sector_map();
+ }
+ TRACE_EXIT;
+}
+
+static inline SectorMap cvt2map(unsigned int sector)
+{
+ return 1 << (((sector & 0x7fffff) - 1) % FT_SECTORS_PER_SEGMENT);
+}
+
+static inline int cvt2segment(unsigned int sector)
+{
+ return ((sector & 0x7fffff) - 1) / FT_SECTORS_PER_SEGMENT;
+}
+
+static int forward_seek_entry(int segment_id,
+ SectorCount **ptr,
+ SectorMap *map)
+{
+ unsigned int sector;
+ int segment;
+
+ do {
+ sector = get_sector((*ptr)++);
+ segment = cvt2segment(sector);
+ } while (sector != 0 && segment < segment_id);
+ (*ptr) --; /* point to first sector >= segment_id */
+ /* Get all sectors in segment_id
+ */
+ if (sector == 0 || segment != segment_id) {
+ *map = 0;
+ return 0;
+ } else if ((sector & 0x800000) &&
+ (ft_format_code == fmt_var || ft_format_code == fmt_big)) {
+ *map = EMPTY_SEGMENT;
+ return FT_SECTORS_PER_SEGMENT;
+ } else {
+ int count = 1;
+ SectorCount *tmp_ptr = (*ptr) + 1;
+
+ *map = cvt2map(sector);
+ while ((sector = get_sector(tmp_ptr++)) != 0 &&
+ (segment = cvt2segment(sector)) == segment_id) {
+ *map |= cvt2map(sector);
+ ++count;
+ }
+ return count;
+ }
+}
+
+static int backwards_seek_entry(int segment_id,
+ SectorCount **ptr,
+ SectorMap *map)
+{
+ unsigned int sector;
+ int segment; /* max unsigned int */
+
+ if (*ptr <= (SectorCount *)bad_sector_map) {
+ *map = 0;
+ return 0;
+ }
+ do {
+ sector = get_sector(--(*ptr));
+ segment = cvt2segment(sector);
+ } while (*ptr > (SectorCount *)bad_sector_map && segment > segment_id);
+ if (segment > segment_id) { /* at start of list, no entry found */
+ *map = 0;
+ return 0;
+ } else if (segment < segment_id) {
+ /* before smaller entry, adjust for overshoot */
+ (*ptr) ++;
+ *map = 0;
+ return 0;
+ } else if ((sector & 0x800000) &&
+ (ft_format_code == fmt_big || ft_format_code == fmt_var)) {
+ *map = EMPTY_SEGMENT;
+ return FT_SECTORS_PER_SEGMENT;
+ } else { /* get all sectors in segment_id */
+ int count = 1;
+
+ *map = cvt2map(sector);
+ while(*ptr > (SectorCount *)bad_sector_map) {
+ sector = get_sector(--(*ptr));
+ segment = cvt2segment(sector);
+ if (segment != segment_id) {
+ break;
+ }
+ *map |= cvt2map(sector);
+ ++count;
+ }
+ if (segment < segment_id) {
+ (*ptr) ++;
+ }
+ return count;
+ }
+}
+
+#if 0
+static void ftape_put_bad_sector_entry(int segment_id, SectorMap new_map)
+{
+ SectorCount *ptr = (SectorCount *)bad_sector_map;
+ int count;
+ int new_count;
+ SectorMap map;
+ TRACE_FUN(ft_t_any);
+
+ if (ft_format_code == fmt_1100ft ||
+ ft_format_code == fmt_var ||
+ ft_format_code == fmt_big) {
+ count = forward_seek_entry(segment_id, &ptr, &map);
+ new_count = count_ones(new_map);
+ /* If format code == 4 put empty segment instead of 32
+ * bad sectors.
+ */
+ if (ft_format_code == fmt_var || ft_format_code == fmt_big) {
+ if (new_count == FT_SECTORS_PER_SEGMENT) {
+ new_count = 1;
+ }
+ if (count == FT_SECTORS_PER_SEGMENT) {
+ count = 1;
+ }
+ }
+ if (count != new_count) {
+ /* insert (or delete if < 0) new_count - count
+ * entries. Move trailing part of list
+ * including terminating 0.
+ */
+ SectorCount *hi_ptr = ptr;
+
+ do {
+ } while (get_sector(hi_ptr++) != 0);
+ /* Note: ptr is of type byte *, and each bad sector
+ * consumes 3 bytes.
+ */
+ memmove(ptr + new_count, ptr + count,
+ (size_t)(hi_ptr - (ptr + count))*sizeof(SectorCount));
+ }
+ TRACE(ft_t_noise, "putting map 0x%08x at %p, segment %d",
+ (unsigned int)new_map, ptr, segment_id);
+ if (new_count == 1 && new_map == EMPTY_SEGMENT) {
+ put_sector(ptr++, (0x800001 +
+ segment_id *
+ FT_SECTORS_PER_SEGMENT));
+ } else {
+ int i = 0;
+
+ while (new_map) {
+ if (new_map & 1) {
+ put_sector(ptr++,
+ 1 + segment_id *
+ FT_SECTORS_PER_SEGMENT + i);
+ }
+ ++i;
+ new_map >>= 1;
+ }
+ }
+ } else {
+ ((SectorMap *) bad_sector_map)[segment_id] = new_map;
+ }
+ TRACE_EXIT;
+}
+#endif /* 0 */
+
+SectorMap ftape_get_bad_sector_entry(int segment_id)
+{
+ if (ft_used_header_segment == -1) {
+ /* When reading header segment we'll need a blank map.
+ */
+ return 0;
+ } else if (bsm_hash_ptr != NULL) {
+ /* Invariants:
+ * map - mask value returned on last call.
+ * bsm_hash_ptr - points to first sector greater or equal to
+ * first sector in last_referenced segment.
+ * last_referenced - segment id used in the last call,
+ * sector and map belong to this id.
+ * This code is designed for sequential access and retries.
+ * For true random access it may have to be redesigned.
+ */
+ static int last_reference = -1;
+ static SectorMap map;
+
+ if (segment_id > last_reference) {
+ /* Skip all sectors before segment_id
+ */
+ forward_seek_entry(segment_id, &bsm_hash_ptr, &map);
+ } else if (segment_id < last_reference) {
+ /* Skip backwards until begin of buffer or
+ * first sector in segment_id
+ */
+ backwards_seek_entry(segment_id, &bsm_hash_ptr, &map);
+ } /* segment_id == last_reference : keep map */
+ last_reference = segment_id;
+ return map;
+ } else {
+ return ((SectorMap *) bad_sector_map)[segment_id];
+ }
+}
+
+/* This is simply here to prevent us from overwriting other kernel
+ * data. Writes will result in NULL Pointer dereference.
+ */
+void ftape_init_bsm(void)
+{
+ bad_sector_map = NULL;
+ bsm_hash_ptr = NULL;
+}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-04 15:33:30 +0000