diff options
Diffstat (limited to 'drivers/char/ftape/zftape/zftape-write.c')
| -rw-r--r-- | drivers/char/ftape/zftape/zftape-write.c | 483 |
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 */ -} |