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-rw-r--r--drivers/char/ftape/zftape/zftape-write.c483
1 files changed, 0 insertions, 483 deletions
diff --git a/drivers/char/ftape/zftape/zftape-write.c b/drivers/char/ftape/zftape/zftape-write.c
deleted file mode 100644
index 94327b8..0000000
--- a/drivers/char/ftape/zftape/zftape-write.c
+++ /dev/null
@@ -1,483 +0,0 @@
-/*
- * Copyright (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/zftape/zftape-write.c,v $
- * $Revision: 1.3 $
- * $Date: 1997/11/06 00:50:29 $
- *
- * This file contains the writing code
- * for the QIC-117 floppy-tape driver for Linux.
- */
-
-#include <linux/errno.h>
-#include <linux/mm.h>
-
-#include <linux/zftape.h>
-
-#include <asm/uaccess.h>
-
-#include "../zftape/zftape-init.h"
-#include "../zftape/zftape-eof.h"
-#include "../zftape/zftape-ctl.h"
-#include "../zftape/zftape-write.h"
-#include "../zftape/zftape-read.h"
-#include "../zftape/zftape-rw.h"
-#include "../zftape/zftape-vtbl.h"
-
-/* Global vars.
- */
-
-/* Local vars.
- */
-static int last_write_failed;
-static int need_flush;
-
-void zft_prevent_flush(void)
-{
- need_flush = 0;
-}
-
-static int zft_write_header_segments(__u8* buffer)
-{
- int header_1_ok = 0;
- int header_2_ok = 0;
- unsigned int time_stamp;
- TRACE_FUN(ft_t_noise);
-
- TRACE_CATCH(ftape_abort_operation(),);
- ftape_seek_to_bot(); /* prevents extra rewind */
- if (GET4(buffer, 0) != FT_HSEG_MAGIC) {
- TRACE_ABORT(-EIO, ft_t_err,
- "wrong header signature found, aborting");
- }
- /* Be optimistic: */
- PUT4(buffer, FT_SEG_CNT,
- zft_written_segments + GET4(buffer, FT_SEG_CNT) + 2);
- if ((time_stamp = zft_get_time()) != 0) {
- PUT4(buffer, FT_WR_DATE, time_stamp);
- if (zft_label_changed) {
- PUT4(buffer, FT_LABEL_DATE, time_stamp);
- }
- }
- TRACE(ft_t_noise,
- "writing first header segment %d", ft_header_segment_1);
- header_1_ok = zft_verify_write_segments(ft_header_segment_1,
- buffer, FT_SEGMENT_SIZE,
- zft_deblock_buf) >= 0;
- TRACE(ft_t_noise,
- "writing second header segment %d", ft_header_segment_2);
- header_2_ok = zft_verify_write_segments(ft_header_segment_2,
- buffer, FT_SEGMENT_SIZE,
- zft_deblock_buf) >= 0;
- if (!header_1_ok) {
- TRACE(ft_t_warn, "Warning: "
- "update of first header segment failed");
- }
- if (!header_2_ok) {
- TRACE(ft_t_warn, "Warning: "
- "update of second header segment failed");
- }
- if (!header_1_ok && !header_2_ok) {
- TRACE_ABORT(-EIO, ft_t_err, "Error: "
- "update of both header segments failed.");
- }
- TRACE_EXIT 0;
-}
-
-int zft_update_header_segments(void)
-{
- TRACE_FUN(ft_t_noise);
-
- /* must NOT use zft_write_protected, as it also includes the
- * file access mode. But we also want to update when soft
- * write protection is enabled (O_RDONLY)
- */
- if (ft_write_protected || zft_old_ftape) {
- TRACE_ABORT(0, ft_t_noise, "Tape set read-only: no update");
- }
- if (!zft_header_read) {
- TRACE_ABORT(0, ft_t_noise, "Nothing to update");
- }
- if (!zft_header_changed) {
- zft_header_changed = zft_written_segments > 0;
- }
- if (!zft_header_changed && !zft_volume_table_changed) {
- TRACE_ABORT(0, ft_t_noise, "Nothing to update");
- }
- TRACE(ft_t_noise, "Updating header segments");
- if (ftape_get_status()->fti_state == writing) {
- TRACE_CATCH(ftape_loop_until_writes_done(),);
- }
- TRACE_CATCH(ftape_abort_operation(),);
-
- zft_deblock_segment = -1; /* invalidate the cache */
- if (zft_header_changed) {
- TRACE_CATCH(zft_write_header_segments(zft_hseg_buf),);
- }
- if (zft_volume_table_changed) {
- TRACE_CATCH(zft_update_volume_table(ft_first_data_segment),);
- }
- zft_header_changed =
- zft_volume_table_changed =
- zft_label_changed =
- zft_written_segments = 0;
- TRACE_CATCH(ftape_abort_operation(),);
- ftape_seek_to_bot();
- TRACE_EXIT 0;
-}
-
-static int read_merge_buffer(int seg_pos, __u8 *buffer, int offset, int seg_sz)
-{
- int result = 0;
- const ft_trace_t old_tracing = TRACE_LEVEL;
- TRACE_FUN(ft_t_flow);
-
- if (zft_qic_mode) {
- /* writing in the middle of a volume is NOT allowed
- *
- */
- TRACE(ft_t_noise, "No need to read a segment");
- memset(buffer + offset, 0, seg_sz - offset);
- TRACE_EXIT 0;
- }
- TRACE(ft_t_any, "waiting");
- ftape_start_writing(FT_WR_MULTI);
- TRACE_CATCH(ftape_loop_until_writes_done(),);
-
- TRACE(ft_t_noise, "trying to read segment %d from offset %d",
- seg_pos, offset);
- SET_TRACE_LEVEL(ft_t_bug);
- result = zft_fetch_segment_fraction(seg_pos, buffer,
- FT_RD_SINGLE,
- offset, seg_sz - offset);
- SET_TRACE_LEVEL(old_tracing);
- if (result != (seg_sz - offset)) {
- TRACE(ft_t_noise, "Ignore error: read_segment() result: %d",
- result);
- memset(buffer + offset, 0, seg_sz - offset);
- }
- TRACE_EXIT 0;
-}
-
-/* flush the write buffer to tape and write an eof-marker at the
- * current position if not in raw mode. This function always
- * positions the tape before the eof-marker. _ftape_close() should
- * then advance to the next segment.
- *
- * the parameter "finish_volume" describes whether to position before
- * or after the possibly created file-mark. We always position after
- * the file-mark when called from ftape_close() and a flush was needed
- * (that is ftape_write() was the last tape operation before calling
- * ftape_flush) But we always position before the file-mark when this
- * function get's called from outside ftape_close()
- */
-int zft_flush_buffers(void)
-{
- int result;
- int data_remaining;
- int this_segs_size;
- TRACE_FUN(ft_t_flow);
-
- TRACE(ft_t_data_flow,
- "entered, ftape_state = %d", ftape_get_status()->fti_state);
- if (ftape_get_status()->fti_state != writing && !need_flush) {
- TRACE_ABORT(0, ft_t_noise, "no need for flush");
- }
- zft_io_state = zft_idle; /* triggers some initializations for the
- * read and write routines
- */
- if (last_write_failed) {
- ftape_abort_operation();
- TRACE_EXIT -EIO;
- }
- TRACE(ft_t_noise, "flushing write buffers");
- this_segs_size = zft_get_seg_sz(zft_pos.seg_pos);
- if (this_segs_size == zft_pos.seg_byte_pos) {
- zft_pos.seg_pos ++;
- data_remaining = zft_pos.seg_byte_pos = 0;
- } else {
- data_remaining = zft_pos.seg_byte_pos;
- }
- /* If there is any data not written to tape yet, append zero's
- * up to the end of the sector (if using compression) or merge
- * it with the data existing on the tape Then write the
- * segment(s) to tape.
- */
- TRACE(ft_t_noise, "Position:\n"
- KERN_INFO "seg_pos : %d\n"
- KERN_INFO "byte pos : %d\n"
- KERN_INFO "remaining: %d",
- zft_pos.seg_pos, zft_pos.seg_byte_pos, data_remaining);
- if (data_remaining > 0) {
- do {
- this_segs_size = zft_get_seg_sz(zft_pos.seg_pos);
- if (this_segs_size > data_remaining) {
- TRACE_CATCH(read_merge_buffer(zft_pos.seg_pos,
- zft_deblock_buf,
- data_remaining,
- this_segs_size),
- last_write_failed = 1);
- }
- result = ftape_write_segment(zft_pos.seg_pos,
- zft_deblock_buf,
- FT_WR_MULTI);
- if (result != this_segs_size) {
- TRACE(ft_t_err, "flush buffers failed");
- zft_pos.tape_pos -= zft_pos.seg_byte_pos;
- zft_pos.seg_byte_pos = 0;
-
- last_write_failed = 1;
- TRACE_EXIT result;
- }
- zft_written_segments ++;
- TRACE(ft_t_data_flow,
- "flush, moved out buffer: %d", result);
- /* need next segment for more data (empty segments?)
- */
- if (result < data_remaining) {
- if (result > 0) {
- /* move remainder to buffer beginning
- */
- memmove(zft_deblock_buf,
- zft_deblock_buf + result,
- FT_SEGMENT_SIZE - result);
- }
- }
- data_remaining -= result;
- zft_pos.seg_pos ++;
- } while (data_remaining > 0);
- TRACE(ft_t_any, "result: %d", result);
- zft_deblock_segment = --zft_pos.seg_pos;
- if (data_remaining == 0) { /* first byte next segment */
- zft_pos.seg_byte_pos = this_segs_size;
- } else { /* after data previous segment, data_remaining < 0 */
- zft_pos.seg_byte_pos = data_remaining + result;
- }
- } else {
- TRACE(ft_t_noise, "zft_deblock_buf empty");
- zft_pos.seg_pos --;
- zft_pos.seg_byte_pos = zft_get_seg_sz (zft_pos.seg_pos);
- ftape_start_writing(FT_WR_MULTI);
- }
- TRACE(ft_t_any, "waiting");
- if ((result = ftape_loop_until_writes_done()) < 0) {
- /* that's really bad. What to to with zft_tape_pos?
- */
- TRACE(ft_t_err, "flush buffers failed");
- }
- TRACE(ft_t_any, "zft_seg_pos: %d, zft_seg_byte_pos: %d",
- zft_pos.seg_pos, zft_pos.seg_byte_pos);
- last_write_failed =
- need_flush = 0;
- TRACE_EXIT result;
-}
-
-/* return-value: the number of bytes removed from the user-buffer
- *
- * out:
- * int *write_cnt: how much actually has been moved to the
- * zft_deblock_buf
- * int req_len : MUST NOT BE CHANGED, except at EOT, in
- * which case it may be adjusted
- * in :
- * char *buff : the user buffer
- * int buf_pos_write : copy of buf_len_wr int
- * this_segs_size : the size in bytes of the actual segment
- * char
- * *zft_deblock_buf : zft_deblock_buf
- */
-static int zft_simple_write(int *cnt,
- __u8 *dst_buf, const int seg_sz,
- const __u8 __user *src_buf, const int req_len,
- const zft_position *pos,const zft_volinfo *volume)
-{
- int space_left;
- TRACE_FUN(ft_t_flow);
-
- /* volume->size holds the tape capacity while volume is open */
- if (pos->tape_pos + volume->blk_sz > volume->size) {
- TRACE_EXIT -ENOSPC;
- }
- /* remaining space in this segment, NOT zft_deblock_buf
- */
- space_left = seg_sz - pos->seg_byte_pos;
- *cnt = req_len < space_left ? req_len : space_left;
- if (copy_from_user(dst_buf + pos->seg_byte_pos, src_buf, *cnt) != 0) {
- TRACE_EXIT -EFAULT;
- }
- TRACE_EXIT *cnt;
-}
-
-static int check_write_access(int req_len,
- const zft_volinfo **volume,
- zft_position *pos,
- const unsigned int blk_sz)
-{
- int result;
- TRACE_FUN(ft_t_flow);
-
- if ((req_len % zft_blk_sz) != 0) {
- TRACE_ABORT(-EINVAL, ft_t_info,
- "write-count %d must be multiple of block-size %d",
- req_len, blk_sz);
- }
- if (zft_io_state == zft_writing) {
- /* all other error conditions have been checked earlier
- */
- TRACE_EXIT 0;
- }
- zft_io_state = zft_idle;
- TRACE_CATCH(zft_check_write_access(pos),);
- /* If we haven't read the header segment yet, do it now.
- * This will verify the configuration, get the bad sector
- * table and read the volume table segment
- */
- if (!zft_header_read) {
- TRACE_CATCH(zft_read_header_segments(),);
- }
- /* fine. Now the tape is either at BOT or at EOD,
- * Write start of volume now
- */
- TRACE_CATCH(zft_open_volume(pos, blk_sz, zft_use_compression),);
- *volume = zft_find_volume(pos->seg_pos);
- DUMP_VOLINFO(ft_t_noise, "", *volume);
- zft_just_before_eof = 0;
- /* now merge with old data if necessary */
- if (!zft_qic_mode && pos->seg_byte_pos != 0){
- result = zft_fetch_segment(pos->seg_pos,
- zft_deblock_buf,
- FT_RD_SINGLE);
- if (result < 0) {
- if (result == -EINTR || result == -ENOSPC) {
- TRACE_EXIT result;
- }
- TRACE(ft_t_noise,
- "ftape_read_segment() result: %d. "
- "This might be normal when using "
- "a newly\nformatted tape", result);
- memset(zft_deblock_buf, '\0', pos->seg_byte_pos);
- }
- }
- zft_io_state = zft_writing;
- TRACE_EXIT 0;
-}
-
-static int fill_deblock_buf(__u8 *dst_buf, const int seg_sz,
- zft_position *pos, const zft_volinfo *volume,
- const char __user *usr_buf, const int req_len)
-{
- int cnt = 0;
- int result = 0;
- TRACE_FUN(ft_t_flow);
-
- if (seg_sz == 0) {
- TRACE_ABORT(0, ft_t_data_flow, "empty segment");
- }
- TRACE(ft_t_data_flow, "\n"
- KERN_INFO "remaining req_len: %d\n"
- KERN_INFO " buf_pos: %d",
- req_len, pos->seg_byte_pos);
- /* zft_deblock_buf will not contain a valid segment any longer */
- zft_deblock_segment = -1;
- if (zft_use_compression) {
- TRACE_CATCH(zft_cmpr_lock(1 /* try to load */),);
- TRACE_CATCH(result= (*zft_cmpr_ops->write)(&cnt,
- dst_buf, seg_sz,
- usr_buf, req_len,
- pos, volume),);
- } else {
- TRACE_CATCH(result= zft_simple_write(&cnt,
- dst_buf, seg_sz,
- usr_buf, req_len,
- pos, volume),);
- }
- pos->volume_pos += result;
- pos->seg_byte_pos += cnt;
- pos->tape_pos += cnt;
- TRACE(ft_t_data_flow, "\n"
- KERN_INFO "removed from user-buffer : %d bytes.\n"
- KERN_INFO "copied to zft_deblock_buf: %d bytes.\n"
- KERN_INFO "zft_tape_pos : " LL_X " bytes.",
- result, cnt, LL(pos->tape_pos));
- TRACE_EXIT result;
-}
-
-
-/* called by the kernel-interface routine "zft_write()"
- */
-int _zft_write(const char __user *buff, int req_len)
-{
- int result = 0;
- int written = 0;
- int write_cnt;
- int seg_sz;
- static const zft_volinfo *volume = NULL;
- TRACE_FUN(ft_t_flow);
-
- zft_resid = req_len;
- last_write_failed = 1; /* reset to 0 when successful */
- /* check if write is allowed
- */
- TRACE_CATCH(check_write_access(req_len, &volume,&zft_pos,zft_blk_sz),);
- while (req_len > 0) {
- /* Allow us to escape from this loop with a signal !
- */
- FT_SIGNAL_EXIT(_DONT_BLOCK);
- seg_sz = zft_get_seg_sz(zft_pos.seg_pos);
- if ((write_cnt = fill_deblock_buf(zft_deblock_buf,
- seg_sz,
- &zft_pos,
- volume,
- buff,
- req_len)) < 0) {
- zft_resid -= written;
- if (write_cnt == -ENOSPC) {
- /* leave the remainder to flush_buffers()
- */
- TRACE(ft_t_info, "No space left on device");
- last_write_failed = 0;
- if (!need_flush) {
- need_flush = written > 0;
- }
- TRACE_EXIT written > 0 ? written : -ENOSPC;
- } else {
- TRACE_EXIT result;
- }
- }
- if (zft_pos.seg_byte_pos == seg_sz) {
- TRACE_CATCH(ftape_write_segment(zft_pos.seg_pos,
- zft_deblock_buf,
- FT_WR_ASYNC),
- zft_resid -= written);
- zft_written_segments ++;
- zft_pos.seg_byte_pos = 0;
- zft_deblock_segment = zft_pos.seg_pos;
- ++zft_pos.seg_pos;
- }
- written += write_cnt;
- buff += write_cnt;
- req_len -= write_cnt;
- } /* while (req_len > 0) */
- TRACE(ft_t_data_flow, "remaining in blocking buffer: %d",
- zft_pos.seg_byte_pos);
- TRACE(ft_t_data_flow, "just written bytes: %d", written);
- last_write_failed = 0;
- zft_resid -= written;
- need_flush = need_flush || written > 0;
- TRACE_EXIT written; /* bytes written */
-}