diff options
| -rw-r--r-- | Documentation/scsi/st.txt | 4 | ||||
| -rw-r--r-- | drivers/scsi/st.c | 21 | ||||
| -rw-r--r-- | drivers/scsi/st.h | 1 | ||||
| -rw-r--r-- | include/linux/mtio.h | 1 |
4 files changed, 24 insertions, 3 deletions
diff --git a/Documentation/scsi/st.txt b/Documentation/scsi/st.txt index 691ca292c24d..685bf3582abe 100644 --- a/Documentation/scsi/st.txt +++ b/Documentation/scsi/st.txt @@ -390,6 +390,10 @@ MTSETDRVBUFFER MT_ST_SYSV sets the SYSV semantics (mode) MT_ST_NOWAIT enables immediate mode (i.e., don't wait for the command to finish) for some commands (e.g., rewind) + MT_ST_NOWAIT_EOF enables immediate filemark mode (i.e. when + writing a filemark, don't wait for it to complete). Please + see the BASICS note about MTWEOFI with respect to the + possible dangers of writing immediate filemarks. MT_ST_SILI enables setting the SILI bit in SCSI commands when reading in variable block mode to enhance performance when reading blocks shorter than the byte count; set this only diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index 9262cdfa4b23..8c663e16fd02 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -1106,6 +1106,12 @@ static int check_tape(struct scsi_tape *STp, struct file *filp) STp->drv_buffer)); } STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0; + if (!STp->drv_buffer && STp->immediate_filemark) { + printk(KERN_WARNING + "%s: non-buffered tape: disabling writing immediate filemarks\n", + name); + STp->immediate_filemark = 0; + } } st_release_request(SRpnt); SRpnt = NULL; @@ -1314,6 +1320,8 @@ static int st_flush(struct file *filp, fl_owner_t id) memset(cmd, 0, MAX_COMMAND_SIZE); cmd[0] = WRITE_FILEMARKS; + if (STp->immediate_filemark) + cmd[1] = 1; cmd[4] = 1 + STp->two_fm; SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE, @@ -2181,8 +2189,9 @@ static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm, char name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions, STp->scsi2_logical); printk(KERN_INFO - "%s: sysv: %d nowait: %d sili: %d\n", name, STm->sysv, STp->immediate, - STp->sili); + "%s: sysv: %d nowait: %d sili: %d nowait_filemark: %d\n", + name, STm->sysv, STp->immediate, STp->sili, + STp->immediate_filemark); printk(KERN_INFO "%s: debugging: %d\n", name, debugging); } @@ -2224,6 +2233,7 @@ static int st_set_options(struct scsi_tape *STp, long options) STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0; STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0; STp->immediate = (options & MT_ST_NOWAIT) != 0; + STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0; STm->sysv = (options & MT_ST_SYSV) != 0; STp->sili = (options & MT_ST_SILI) != 0; DEB( debugging = (options & MT_ST_DEBUGGING) != 0; @@ -2255,6 +2265,8 @@ static int st_set_options(struct scsi_tape *STp, long options) STp->scsi2_logical = value; if ((options & MT_ST_NOWAIT) != 0) STp->immediate = value; + if ((options & MT_ST_NOWAIT_EOF) != 0) + STp->immediate_filemark = value; if ((options & MT_ST_SYSV) != 0) STm->sysv = value; if ((options & MT_ST_SILI) != 0) @@ -2714,7 +2726,8 @@ static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned lon cmd[0] = WRITE_FILEMARKS; if (cmd_in == MTWSM) cmd[1] = 2; - if (cmd_in == MTWEOFI) + if (cmd_in == MTWEOFI || + (cmd_in == MTWEOF && STp->immediate_filemark)) cmd[1] |= 1; cmd[2] = (arg >> 16); cmd[3] = (arg >> 8); @@ -4093,6 +4106,7 @@ static int st_probe(struct device *dev) tpnt->scsi2_logical = ST_SCSI2LOGICAL; tpnt->sili = ST_SILI; tpnt->immediate = ST_NOWAIT; + tpnt->immediate_filemark = 0; tpnt->default_drvbuffer = 0xff; /* No forced buffering */ tpnt->partition = 0; tpnt->new_partition = 0; @@ -4478,6 +4492,7 @@ st_options_show(struct device *dev, struct device_attribute *attr, char *buf) options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0; options |= STm->sysv ? MT_ST_SYSV : 0; options |= STp->immediate ? MT_ST_NOWAIT : 0; + options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0; options |= STp->sili ? MT_ST_SILI : 0; l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options); diff --git a/drivers/scsi/st.h b/drivers/scsi/st.h index f91a67c6d968..ea35632b986c 100644 --- a/drivers/scsi/st.h +++ b/drivers/scsi/st.h @@ -120,6 +120,7 @@ struct scsi_tape { unsigned char c_algo; /* compression algorithm */ unsigned char pos_unknown; /* after reset position unknown */ unsigned char sili; /* use SILI when reading in variable b mode */ + unsigned char immediate_filemark; /* write filemark immediately */ int tape_type; int long_timeout; /* timeout for commands known to take long time */ diff --git a/include/linux/mtio.h b/include/linux/mtio.h index 8f825756c459..18543e2db06f 100644 --- a/include/linux/mtio.h +++ b/include/linux/mtio.h @@ -194,6 +194,7 @@ struct mtpos { #define MT_ST_SYSV 0x1000 #define MT_ST_NOWAIT 0x2000 #define MT_ST_SILI 0x4000 +#define MT_ST_NOWAIT_EOF 0x8000 /* The mode parameters to be controlled. Parameter chosen with bits 20-28 */ #define MT_ST_CLEAR_DEFAULT 0xfffff |