[PATCH 0/5] scsi_debug: increase the amount of ram that scsi_ram can allocate

[PATCH 0/5] scsi_debug: increase the amount of ram that scsi_ram can allocate

[FUJITA Tomonori]

Currently, the maximum amount of RAM that scsi_debug can actually
allocate is 4GB. This patchset increase it to 2TB.

Here's an example, scsi_debug allocates 6GB ram and exports it as if
it were 6GB disk.

fujita@rose:/sys/bus/pseudo/drivers/scsi_debug$ cat virtual_gb
0
fujita@rose:/sys/bus/pseudo/drivers/scsi_debug$ cat dev_size_mb
6144

scsi3 : scsi_debug, version 1.81 [20070104], dev_size_mb=6144, opts=0x0
scsi 3:0:0:0: Direct-Access     Linux    scsi_debug       0004 PQ: 0 ANSI: 5
sd 3:0:0:0: [sdc] 12582912 512-byte hardware sectors (6442 MB)


This patchset also include minor cleanup.

This is against scsi-misc with the scsi_build_sense_buffer helper
patchset and the scsi_debug lba fix:

http://marc.info/?l=linux-scsi&m=120640632301595&w=2

http://marc.info/?l=linux-scsi&m=120643343003171&w=2

[PATCH 1/5] scsi_debug: remove unnecessary sdebug_store_size

[FUJITA Tomonori]

sdebug_store_size doesn't need to be static global. It's used at
startup only.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/scsi/scsi_debug.c |   13 ++++++-------
 1 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 65c88dd..4e93b69 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -148,7 +148,6 @@ static int scsi_debug_cmnd_count = 0;
 #define DEV_READONLY(TGT)      (0)
 #define DEV_REMOVEABLE(TGT)    (0)
 
-static unsigned int sdebug_store_size;	/* in bytes */
 static unsigned int sdebug_store_sectors;
 static sector_t sdebug_capacity;	/* in sectors */
 
@@ -1969,7 +1968,8 @@ static void __init init_all_queued(void)
 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
 }
 
-static void __init sdebug_build_parts(unsigned char * ramp)
+static void __init sdebug_build_parts(unsigned char *ramp,
+				      unsigned int store_size)
 {
 	struct partition * pp;
 	int starts[SDEBUG_MAX_PARTS + 2];
@@ -1977,7 +1977,7 @@ static void __init sdebug_build_parts(unsigned char * ramp)
 	int heads_by_sects, start_sec, end_sec;
 
 	/* assume partition table already zeroed */
-	if ((scsi_debug_num_parts < 1) || (sdebug_store_size < 1048576))
+	if ((scsi_debug_num_parts < 1) || (store_size < 1048576))
 		return;
 	if (scsi_debug_num_parts > SDEBUG_MAX_PARTS) {
 		scsi_debug_num_parts = SDEBUG_MAX_PARTS;
@@ -2505,8 +2505,8 @@ static int __init scsi_debug_init(void)
 
 	if (scsi_debug_dev_size_mb < 1)
 		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
-	sdebug_store_size = (unsigned int)scsi_debug_dev_size_mb * 1048576;
-	sdebug_store_sectors = sdebug_store_size / SECT_SIZE;
+	sz = (unsigned int)scsi_debug_dev_size_mb * 1048576;
+	sdebug_store_sectors = sz / SECT_SIZE;
 	if (scsi_debug_virtual_gb > 0) {
 		sdebug_capacity = 2048 * 1024;
 		sdebug_capacity *= scsi_debug_virtual_gb;
@@ -2530,7 +2530,6 @@ static int __init scsi_debug_init(void)
 			       (sdebug_sectors_per * sdebug_heads);
 	}
 
-	sz = sdebug_store_size;
 	fake_storep = vmalloc(sz);
 	if (NULL == fake_storep) {
 		printk(KERN_ERR "scsi_debug_init: out of memory, 1\n");
@@ -2538,7 +2537,7 @@ static int __init scsi_debug_init(void)
 	}
 	memset(fake_storep, 0, sz);
 	if (scsi_debug_num_parts > 0)
-		sdebug_build_parts(fake_storep);
+		sdebug_build_parts(fake_storep, sz);
 
 	ret = device_register(&pseudo_primary);
 	if (ret < 0) {
-- 
1.5.3.7

[PATCH 2/5] scsi_debug: sweep up sdebug_capacity calculation

[FUJITA Tomonori]

sdebug_capacity is calculated at five different places. This add a
helper function to calculate sdebug_capacity to sweep up the
duplicatated code.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/scsi/scsi_debug.c |   44 +++++++++++++++++---------------------------
 1 files changed, 17 insertions(+), 27 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 4e93b69..70bcee6 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -823,6 +823,14 @@ static int resp_start_stop(struct scsi_cmnd * scp,
 	return 0;
 }
 
+static sector_t get_sdebug_capacity(void)
+{
+	if (scsi_debug_virtual_gb > 0)
+		return 2048 * 1024 * scsi_debug_virtual_gb;
+	else
+		return sdebug_store_sectors;
+}
+
 #define SDEBUG_READCAP_ARR_SZ 8
 static int resp_readcap(struct scsi_cmnd * scp,
 			struct sdebug_dev_info * devip)
@@ -834,11 +842,7 @@ static int resp_readcap(struct scsi_cmnd * scp,
 	if ((errsts = check_readiness(scp, 1, devip)))
 		return errsts;
 	/* following just in case virtual_gb changed */
-	if (scsi_debug_virtual_gb > 0) {
-		sdebug_capacity = 2048 * 1024;
-		sdebug_capacity *= scsi_debug_virtual_gb;
-	} else
-		sdebug_capacity = sdebug_store_sectors;
+	sdebug_capacity = get_sdebug_capacity();
 	memset(arr, 0, SDEBUG_READCAP_ARR_SZ);
 	if (sdebug_capacity < 0xffffffff) {
 		capac = (unsigned int)sdebug_capacity - 1;
@@ -871,11 +875,7 @@ static int resp_readcap16(struct scsi_cmnd * scp,
 	alloc_len = ((cmd[10] << 24) + (cmd[11] << 16) + (cmd[12] << 8)
 		     + cmd[13]);
 	/* following just in case virtual_gb changed */
-	if (scsi_debug_virtual_gb > 0) {
-		sdebug_capacity = 2048 * 1024;
-		sdebug_capacity *= scsi_debug_virtual_gb;
-	} else
-		sdebug_capacity = sdebug_store_sectors;
+	sdebug_capacity = get_sdebug_capacity();
 	memset(arr, 0, SDEBUG_READCAP16_ARR_SZ);
 	capac = sdebug_capacity - 1;
 	for (k = 0; k < 8; ++k, capac >>= 8)
@@ -1169,13 +1169,9 @@ static int resp_mode_sense(struct scsi_cmnd * scp, int target,
 		offset = 8;
 	}
 	ap = arr + offset;
-	if ((bd_len > 0) && (0 == sdebug_capacity)) {
-		if (scsi_debug_virtual_gb > 0) {
-			sdebug_capacity = 2048 * 1024;
-			sdebug_capacity *= scsi_debug_virtual_gb;
-		} else
-			sdebug_capacity = sdebug_store_sectors;
-	}
+	if ((bd_len > 0) && (!sdebug_capacity))
+		sdebug_capacity = get_sdebug_capacity();
+
 	if (8 == bd_len) {
 		if (sdebug_capacity > 0xfffffffe) {
 			ap[0] = 0xff;
@@ -2392,11 +2388,9 @@ static ssize_t sdebug_virtual_gb_store(struct device_driver * ddp,
 
 	if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) {
 		scsi_debug_virtual_gb = n;
-		if (scsi_debug_virtual_gb > 0) {
-			sdebug_capacity = 2048 * 1024;
-			sdebug_capacity *= scsi_debug_virtual_gb;
-		} else
-			sdebug_capacity = sdebug_store_sectors;
+
+		sdebug_capacity = get_sdebug_capacity();
+
 		return count;
 	}
 	return -EINVAL;
@@ -2507,11 +2501,7 @@ static int __init scsi_debug_init(void)
 		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
 	sz = (unsigned int)scsi_debug_dev_size_mb * 1048576;
 	sdebug_store_sectors = sz / SECT_SIZE;
-	if (scsi_debug_virtual_gb > 0) {
-		sdebug_capacity = 2048 * 1024;
-		sdebug_capacity *= scsi_debug_virtual_gb;
-	} else
-		sdebug_capacity = sdebug_store_sectors;
+	sdebug_capacity = get_sdebug_capacity();
 
 	/* play around with geometry, don't waste too much on track 0 */
 	sdebug_heads = 8;
-- 
1.5.3.7

[PATCH 3/5] scsi_debug: remove the duplicated code in resp_read and resp_write

[FUJITA Tomonori]

resp_read and resp_write performs READ_* and WRITE_* commands
respectively. This sweeps up the similar code in them.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/scsi/scsi_debug.c |  116 +++++++++++++++++++-------------------------
 1 files changed, 50 insertions(+), 66 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 70bcee6..c98559e 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1468,25 +1468,53 @@ static int resp_log_sense(struct scsi_cmnd * scp,
 		    min(len, SDEBUG_MAX_INQ_ARR_SZ));
 }
 
-static int resp_read(struct scsi_cmnd * SCpnt, unsigned long long lba,
-		     unsigned int num, struct sdebug_dev_info * devip)
+static int check_device_access_params(struct sdebug_dev_info *devi,
+				      unsigned long long lba, unsigned int num)
 {
-	unsigned long iflags;
-	unsigned int block, from_bottom;
-	unsigned long long u;
-	int ret;
-
 	if (lba + num > sdebug_capacity) {
-		mk_sense_buffer(devip, ILLEGAL_REQUEST, ADDR_OUT_OF_RANGE,
-				0);
+		mk_sense_buffer(devi, ILLEGAL_REQUEST, ADDR_OUT_OF_RANGE, 0);
 		return check_condition_result;
 	}
 	/* transfer length excessive (tie in to block limits VPD page) */
 	if (num > sdebug_store_sectors) {
-		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
-				0);
+		mk_sense_buffer(devi, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB, 0);
 		return check_condition_result;
 	}
+	return 0;
+}
+
+static int do_device_access(struct scsi_cmnd *scmd,
+			    struct sdebug_dev_info *devi,
+			    unsigned long long lba, unsigned int num, int write)
+{
+	int ret;
+	unsigned int block, rest = 0;
+	int (*func)(struct scsi_cmnd *, unsigned char *, int);
+
+	func = write ? fetch_to_dev_buffer : fill_from_dev_buffer;
+
+	block = do_div(lba, sdebug_store_sectors);
+	if (block + num > sdebug_store_sectors)
+		rest = block + num - sdebug_store_sectors;
+
+	ret = func(scmd, fake_storep + (block * SECT_SIZE),
+		   (num - rest) * SECT_SIZE);
+	if (!ret && rest)
+		ret = func(scmd, fake_storep, rest * SECT_SIZE);
+
+	return ret;
+}
+
+static int resp_read(struct scsi_cmnd *SCpnt, unsigned long long lba,
+		     unsigned int num, struct sdebug_dev_info *devip)
+{
+	unsigned long iflags;
+	int ret;
+
+	ret = check_device_access_params(devip, lba, num);
+	if (ret)
+		return ret;
+
 	if ((SCSI_DEBUG_OPT_MEDIUM_ERR & scsi_debug_opts) &&
 	    (lba <= OPT_MEDIUM_ERR_ADDR) &&
 	    ((lba + num) > OPT_MEDIUM_ERR_ADDR)) {
@@ -1505,74 +1533,30 @@ static int resp_read(struct scsi_cmnd * SCpnt, unsigned long long lba,
 		return check_condition_result;
 	}
 	read_lock_irqsave(&atomic_rw, iflags);
-	if ((lba + num) <= sdebug_store_sectors)
-		ret = fill_from_dev_buffer(SCpnt,
-					   fake_storep + (lba * SECT_SIZE),
-			   		   num * SECT_SIZE);
-	else {
-		/* modulo when one arg is 64 bits needs do_div() */
-		u = lba;
-		block = do_div(u, sdebug_store_sectors);
-		from_bottom = 0;
-		if ((block + num) > sdebug_store_sectors)
-			from_bottom = (block + num) - sdebug_store_sectors;
-		ret = fill_from_dev_buffer(SCpnt,
-					   fake_storep + (block * SECT_SIZE),
-			   		   (num - from_bottom) * SECT_SIZE);
-		if ((0 == ret) && (from_bottom > 0))
-			ret = fill_from_dev_buffer(SCpnt, fake_storep,
-						   from_bottom * SECT_SIZE);
-	}
+	ret = do_device_access(SCpnt, devip, lba, num, 0);
 	read_unlock_irqrestore(&atomic_rw, iflags);
 	return ret;
 }
 
-static int resp_write(struct scsi_cmnd * SCpnt, unsigned long long lba,
-		      unsigned int num, struct sdebug_dev_info * devip)
+static int resp_write(struct scsi_cmnd *SCpnt, unsigned long long lba,
+		      unsigned int num, struct sdebug_dev_info *devip)
 {
 	unsigned long iflags;
-	unsigned int block, to_bottom;
-	unsigned long long u;
-	int res;
+	int ret;
 
-	if (lba + num > sdebug_capacity) {
-		mk_sense_buffer(devip, ILLEGAL_REQUEST, ADDR_OUT_OF_RANGE,
-			       	0);
-		return check_condition_result;
-	}
-	/* transfer length excessive (tie in to block limits VPD page) */
-	if (num > sdebug_store_sectors) {
-		mk_sense_buffer(devip, ILLEGAL_REQUEST, INVALID_FIELD_IN_CDB,
-				0);
-		return check_condition_result;
-	}
+	ret = check_device_access_params(devip, lba, num);
+	if (ret)
+		return ret;
 
 	write_lock_irqsave(&atomic_rw, iflags);
-	if ((lba + num) <= sdebug_store_sectors)
-		res = fetch_to_dev_buffer(SCpnt,
-					  fake_storep + (lba * SECT_SIZE),
-			   		  num * SECT_SIZE);
-	else {
-		/* modulo when one arg is 64 bits needs do_div() */
-		u = lba;
-		block = do_div(u, sdebug_store_sectors);
-		to_bottom = 0;
-		if ((block + num) > sdebug_store_sectors)
-			to_bottom = (block + num) - sdebug_store_sectors;
-		res = fetch_to_dev_buffer(SCpnt,
-					  fake_storep + (block * SECT_SIZE),
-			   		  (num - to_bottom) * SECT_SIZE);
-		if ((0 == res) && (to_bottom > 0))
-			res = fetch_to_dev_buffer(SCpnt, fake_storep,
-						  to_bottom * SECT_SIZE);
-	}
+	ret = do_device_access(SCpnt, devip, lba, num, 1);
 	write_unlock_irqrestore(&atomic_rw, iflags);
-	if (-1 == res)
+	if (-1 == ret)
 		return (DID_ERROR << 16);
-	else if ((res < (num * SECT_SIZE)) &&
+	else if ((ret < (num * SECT_SIZE)) &&
 		 (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts))
 		printk(KERN_INFO "scsi_debug: write: cdb indicated=%u, "
-		       " IO sent=%d bytes\n", num * SECT_SIZE, res);
+		       " IO sent=%d bytes\n", num * SECT_SIZE, ret);
 	return 0;
 }
 
-- 
1.5.3.7

[PATCH 4/5] scsi_debug: support large non-fake virtual disk

[FUJITA Tomonori]

Currently, the maximum amount of RAM that scsi_debug can allocate is
4GB. This patch increases it to 2TB; scsi_debug can allocates 2TB
memory and export it as if it were 2TB scsi disk.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/scsi/scsi_debug.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index c98559e..1b6a6d8 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1949,7 +1949,7 @@ static void __init init_all_queued(void)
 }
 
 static void __init sdebug_build_parts(unsigned char *ramp,
-				      unsigned int store_size)
+				      unsigned long store_size)
 {
 	struct partition * pp;
 	int starts[SDEBUG_MAX_PARTS + 2];
@@ -2476,14 +2476,14 @@ static void do_remove_driverfs_files(void)
 
 static int __init scsi_debug_init(void)
 {
-	unsigned int sz;
+	unsigned long sz;
 	int host_to_add;
 	int k;
 	int ret;
 
 	if (scsi_debug_dev_size_mb < 1)
 		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
-	sz = (unsigned int)scsi_debug_dev_size_mb * 1048576;
+	sz = (unsigned long)scsi_debug_dev_size_mb * 1048576;
 	sdebug_store_sectors = sz / SECT_SIZE;
 	sdebug_capacity = get_sdebug_capacity();
 
-- 
1.5.3.7

[PATCH 5/5] scsi_debug: remove unnecessary function declarations

[FUJITA Tomonori]

This patch removes function declarations with moving some
functions. This cleans up them a bit to silence checkpatch.pl. There
is no functional change.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/scsi/scsi_debug.c |  277 ++++++++++++++++++++++-----------------------
 1 files changed, 133 insertions(+), 144 deletions(-)

diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 1b6a6d8..07103c3 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -218,8 +218,6 @@ static DEFINE_RWLOCK(atomic_rw);
 
 static char sdebug_proc_name[] = "scsi_debug";
 
-static int sdebug_driver_probe(struct device *);
-static int sdebug_driver_remove(struct device *);
 static struct bus_type pseudo_lld_bus;
 
 static struct device_driver sdebug_driverfs_driver = {
@@ -235,18 +233,42 @@ static unsigned char ctrl_m_pg[] = {0xa, 10, 2, 0, 0, 0, 0, 0,
 static unsigned char iec_m_pg[] = {0x1c, 0xa, 0x08, 0, 0, 0, 0, 0,
 			           0, 0, 0x0, 0x0};
 
-static struct sdebug_dev_info * devInfoReg(struct scsi_device * sdev);
-static void mk_sense_buffer(struct sdebug_dev_info * devip, int key,
-			    int asc, int asq);
-static void stop_all_queued(void);
-static int stop_queued_cmnd(struct scsi_cmnd * cmnd);
-
 static int sdebug_add_adapter(void);
 static void sdebug_remove_adapter(void);
-static void sdebug_max_tgts_luns(void);
 
-static struct device pseudo_primary;
-static struct bus_type pseudo_lld_bus;
+static void sdebug_max_tgts_luns(void)
+{
+	struct sdebug_host_info *sdbg_host;
+	struct Scsi_Host *hpnt;
+
+	spin_lock(&sdebug_host_list_lock);
+	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
+		hpnt = sdbg_host->shost;
+		if ((hpnt->this_id >= 0) &&
+		    (scsi_debug_num_tgts > hpnt->this_id))
+			hpnt->max_id = scsi_debug_num_tgts + 1;
+		else
+			hpnt->max_id = scsi_debug_num_tgts;
+		/* scsi_debug_max_luns; */
+		hpnt->max_lun = SAM2_WLUN_REPORT_LUNS;
+	}
+	spin_unlock(&sdebug_host_list_lock);
+}
+
+static void mk_sense_buffer(struct sdebug_dev_info *devip, int key,
+			    int asc, int asq)
+{
+	unsigned char *sbuff;
+
+	sbuff = devip->sense_buff;
+	memset(sbuff, 0, SDEBUG_SENSE_LEN);
+
+	scsi_build_sense_buffer(scsi_debug_dsense, sbuff, key, asc, asq);
+
+	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
+		printk(KERN_INFO "scsi_debug:    [sense_key,asc,ascq]: "
+		      "[0x%x,0x%x,0x%x]\n", key, asc, asq);
+}
 
 static void get_data_transfer_info(unsigned char *cmd,
 				   unsigned long long *lba, unsigned int *num)
@@ -1680,52 +1702,9 @@ static void timer_intr_handler(unsigned long indx)
 	spin_unlock_irqrestore(&queued_arr_lock, iflags);
 }
 
-static int scsi_debug_slave_alloc(struct scsi_device * sdp)
-{
-	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-		printk(KERN_INFO "scsi_debug: slave_alloc <%u %u %u %u>\n",
-		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
-	set_bit(QUEUE_FLAG_BIDI, &sdp->request_queue->queue_flags);
-	return 0;
-}
-
-static int scsi_debug_slave_configure(struct scsi_device * sdp)
-{
-	struct sdebug_dev_info * devip;
-
-	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-		printk(KERN_INFO "scsi_debug: slave_configure <%u %u %u %u>\n",
-		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
-	if (sdp->host->max_cmd_len != SCSI_DEBUG_MAX_CMD_LEN)
-		sdp->host->max_cmd_len = SCSI_DEBUG_MAX_CMD_LEN;
-	devip = devInfoReg(sdp);
-	if (NULL == devip)
-		return 1;	/* no resources, will be marked offline */
-	sdp->hostdata = devip;
-	if (sdp->host->cmd_per_lun)
-		scsi_adjust_queue_depth(sdp, SDEBUG_TAGGED_QUEUING,
-					sdp->host->cmd_per_lun);
-	blk_queue_max_segment_size(sdp->request_queue, 256 * 1024);
-	return 0;
-}
-
-static void scsi_debug_slave_destroy(struct scsi_device * sdp)
-{
-	struct sdebug_dev_info * devip =
-				(struct sdebug_dev_info *)sdp->hostdata;
 
-	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-		printk(KERN_INFO "scsi_debug: slave_destroy <%u %u %u %u>\n",
-		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
-	if (devip) {
-		/* make this slot avaliable for re-use */
-		devip->used = 0;
-		sdp->hostdata = NULL;
-	}
-}
-
-struct sdebug_dev_info *sdebug_device_create(struct sdebug_host_info *sdbg_host,
-					     gfp_t flags)
+static struct sdebug_dev_info *
+sdebug_device_create(struct sdebug_host_info *sdbg_host, gfp_t flags)
 {
 	struct sdebug_dev_info *devip;
 
@@ -1789,19 +1768,88 @@ static struct sdebug_dev_info * devInfoReg(struct scsi_device * sdev)
 	return open_devip;
 }
 
-static void mk_sense_buffer(struct sdebug_dev_info * devip, int key,
-			    int asc, int asq)
+static int scsi_debug_slave_alloc(struct scsi_device *sdp)
 {
-	unsigned char *sbuff;
+	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
+		printk(KERN_INFO "scsi_debug: slave_alloc <%u %u %u %u>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	set_bit(QUEUE_FLAG_BIDI, &sdp->request_queue->queue_flags);
+	return 0;
+}
 
-	sbuff = devip->sense_buff;
-	memset(sbuff, 0, SDEBUG_SENSE_LEN);
+static int scsi_debug_slave_configure(struct scsi_device *sdp)
+{
+	struct sdebug_dev_info *devip;
 
-	scsi_build_sense_buffer(scsi_debug_dsense, sbuff, key, asc, asq);
+	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
+		printk(KERN_INFO "scsi_debug: slave_configure <%u %u %u %u>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	if (sdp->host->max_cmd_len != SCSI_DEBUG_MAX_CMD_LEN)
+		sdp->host->max_cmd_len = SCSI_DEBUG_MAX_CMD_LEN;
+	devip = devInfoReg(sdp);
+	if (NULL == devip)
+		return 1;	/* no resources, will be marked offline */
+	sdp->hostdata = devip;
+	if (sdp->host->cmd_per_lun)
+		scsi_adjust_queue_depth(sdp, SDEBUG_TAGGED_QUEUING,
+					sdp->host->cmd_per_lun);
+	blk_queue_max_segment_size(sdp->request_queue, 256 * 1024);
+	return 0;
+}
+
+static void scsi_debug_slave_destroy(struct scsi_device *sdp)
+{
+	struct sdebug_dev_info *devip =
+		(struct sdebug_dev_info *)sdp->hostdata;
 
 	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-		printk(KERN_INFO "scsi_debug:    [sense_key,asc,ascq]: "
-		      "[0x%x,0x%x,0x%x]\n", key, asc, asq);
+		printk(KERN_INFO "scsi_debug: slave_destroy <%u %u %u %u>\n",
+		       sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
+	if (devip) {
+		/* make this slot avaliable for re-use */
+		devip->used = 0;
+		sdp->hostdata = NULL;
+	}
+}
+
+/* Returns 1 if found 'cmnd' and deleted its timer. else returns 0 */
+static int stop_queued_cmnd(struct scsi_cmnd *cmnd)
+{
+	unsigned long iflags;
+	int k;
+	struct sdebug_queued_cmd *sqcp;
+
+	spin_lock_irqsave(&queued_arr_lock, iflags);
+	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
+		sqcp = &queued_arr[k];
+		if (sqcp->in_use && (cmnd == sqcp->a_cmnd)) {
+			del_timer_sync(&sqcp->cmnd_timer);
+			sqcp->in_use = 0;
+			sqcp->a_cmnd = NULL;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&queued_arr_lock, iflags);
+	return (k < SCSI_DEBUG_CANQUEUE) ? 1 : 0;
+}
+
+/* Deletes (stops) timers of all queued commands */
+static void stop_all_queued(void)
+{
+	unsigned long iflags;
+	int k;
+	struct sdebug_queued_cmd *sqcp;
+
+	spin_lock_irqsave(&queued_arr_lock, iflags);
+	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
+		sqcp = &queued_arr[k];
+		if (sqcp->in_use && sqcp->a_cmnd) {
+			del_timer_sync(&sqcp->cmnd_timer);
+			sqcp->in_use = 0;
+			sqcp->a_cmnd = NULL;
+		}
+	}
+	spin_unlock_irqrestore(&queued_arr_lock, iflags);
 }
 
 static int scsi_debug_abort(struct scsi_cmnd * SCpnt)
@@ -1891,46 +1939,6 @@ static int scsi_debug_host_reset(struct scsi_cmnd * SCpnt)
 	return SUCCESS;
 }
 
-/* Returns 1 if found 'cmnd' and deleted its timer. else returns 0 */
-static int stop_queued_cmnd(struct scsi_cmnd * cmnd)
-{
-	unsigned long iflags;
-	int k;
-	struct sdebug_queued_cmd * sqcp;
-
-	spin_lock_irqsave(&queued_arr_lock, iflags);
-	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
-		sqcp = &queued_arr[k];
-		if (sqcp->in_use && (cmnd == sqcp->a_cmnd)) {
-			del_timer_sync(&sqcp->cmnd_timer);
-			sqcp->in_use = 0;
-			sqcp->a_cmnd = NULL;
-			break;
-		}
-	}
-	spin_unlock_irqrestore(&queued_arr_lock, iflags);
-	return (k < SCSI_DEBUG_CANQUEUE) ? 1 : 0;
-}
-
-/* Deletes (stops) timers of all queued commands */
-static void stop_all_queued(void)
-{
-	unsigned long iflags;
-	int k;
-	struct sdebug_queued_cmd * sqcp;
-
-	spin_lock_irqsave(&queued_arr_lock, iflags);
-	for (k = 0; k < SCSI_DEBUG_CANQUEUE; ++k) {
-		sqcp = &queued_arr[k];
-		if (sqcp->in_use && sqcp->a_cmnd) {
-			del_timer_sync(&sqcp->cmnd_timer);
-			sqcp->in_use = 0;
-			sqcp->a_cmnd = NULL;
-		}
-	}
-	spin_unlock_irqrestore(&queued_arr_lock, iflags);
-}
-
 /* Initializes timers in queued array */
 static void __init init_all_queued(void)
 {
@@ -2055,7 +2063,6 @@ static int schedule_resp(struct scsi_cmnd * cmnd,
 		return 0;
 	}
 }
-
 /* Note: The following macros create attribute files in the
    /sys/module/scsi_debug/parameters directory. Unfortunately this
    driver is unaware of a change and cannot trigger auxiliary actions
@@ -2474,6 +2481,17 @@ static void do_remove_driverfs_files(void)
 	driver_remove_file(&sdebug_driverfs_driver, &driver_attr_add_host);
 }
 
+static void pseudo_0_release(struct device *dev)
+{
+	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
+		printk(KERN_INFO "scsi_debug: pseudo_0_release() called\n");
+}
+
+static struct device pseudo_primary = {
+	.bus_id		= "pseudo_0",
+	.release	= pseudo_0_release,
+};
+
 static int __init scsi_debug_init(void)
 {
 	unsigned long sz;
@@ -2588,30 +2606,6 @@ static void __exit scsi_debug_exit(void)
 device_initcall(scsi_debug_init);
 module_exit(scsi_debug_exit);
 
-static void pseudo_0_release(struct device * dev)
-{
-	if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
-		printk(KERN_INFO "scsi_debug: pseudo_0_release() called\n");
-}
-
-static struct device pseudo_primary = {
-	.bus_id		= "pseudo_0",
-	.release	= pseudo_0_release,
-};
-
-static int pseudo_lld_bus_match(struct device *dev,
-                          struct device_driver *dev_driver)
-{
-        return 1;
-}
-
-static struct bus_type pseudo_lld_bus = {
-        .name = "pseudo",
-        .match = pseudo_lld_bus_match,
-	.probe = sdebug_driver_probe,
-	.remove = sdebug_driver_remove,
-};
-
 static void sdebug_release_adapter(struct device * dev)
 {
         struct sdebug_host_info *sdbg_host;
@@ -3011,20 +3005,15 @@ static int sdebug_driver_remove(struct device * dev)
         return 0;
 }
 
-static void sdebug_max_tgts_luns(void)
+static int pseudo_lld_bus_match(struct device *dev,
+				struct device_driver *dev_driver)
 {
-	struct sdebug_host_info * sdbg_host;
-	struct Scsi_Host *hpnt;
-
-	spin_lock(&sdebug_host_list_lock);
-	list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) {
-		hpnt = sdbg_host->shost;
-		if ((hpnt->this_id >= 0) &&
-		    (scsi_debug_num_tgts > hpnt->this_id))
-			hpnt->max_id = scsi_debug_num_tgts + 1;
-		else
-			hpnt->max_id = scsi_debug_num_tgts;
-		hpnt->max_lun = SAM2_WLUN_REPORT_LUNS; /* scsi_debug_max_luns; */
-	}
-	spin_unlock(&sdebug_host_list_lock);
+	return 1;
 }
+
+static struct bus_type pseudo_lld_bus = {
+	.name = "pseudo",
+	.match = pseudo_lld_bus_match,
+	.probe = sdebug_driver_probe,
+	.remove = sdebug_driver_remove,
+};
-- 
1.5.3.7

Re: [PATCH 4/5] scsi_debug: support large non-fake virtual disk

[Douglas Gilbert]

FUJITA Tomonori wrote:
> Currently, the maximum amount of RAM that scsi_debug can allocate is
> 4GB. This patch increases it to 2TB; scsi_debug can allocates 2TB
> memory and export it as if it were 2TB scsi disk.
> 
> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> Cc: Douglas Gilbert <dougg@torque.net>
> Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
> ---
>  drivers/scsi/scsi_debug.c |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
> index c98559e..1b6a6d8 100644
> --- a/drivers/scsi/scsi_debug.c
> +++ b/drivers/scsi/scsi_debug.c
> @@ -1949,7 +1949,7 @@ static void __init init_all_queued(void)
>  }
>  
>  static void __init sdebug_build_parts(unsigned char *ramp,
> -				      unsigned int store_size)
> +				      unsigned long store_size)
>  {
>  	struct partition * pp;
>  	int starts[SDEBUG_MAX_PARTS + 2];
> @@ -2476,14 +2476,14 @@ static void do_remove_driverfs_files(void)
>  
>  static int __init scsi_debug_init(void)
>  {
> -	unsigned int sz;
> +	unsigned long sz;
>  	int host_to_add;
>  	int k;
>  	int ret;
>  
>  	if (scsi_debug_dev_size_mb < 1)
>  		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
> -	sz = (unsigned int)scsi_debug_dev_size_mb * 1048576;
> +	sz = (unsigned long)scsi_debug_dev_size_mb * 1048576;
>  	sdebug_store_sectors = sz / SECT_SIZE;
>  	sdebug_capacity = get_sdebug_capacity();
>  

Tomo,
Unsigned long is 32 bits on i386 (and 64 bits in the LP64
data model). Don't you want 64 bits in all cases? Either
unsigned long long, uint64_t or one of those crappy
kernel typedefs for 64 bits.

BTW I recently removed just about all the "unsigned long"
declarations out of sg3_utils due the uncertainty about the
size of "long".

Doug Gilbert

Re: [PATCH 4/5] scsi_debug: support large non-fake virtual disk

[FUJITA Tomonori]

On Sat, 29 Mar 2008 14:09:29 -0400
Douglas Gilbert <dougg@torque.net> wrote:

> FUJITA Tomonori wrote:
> > Currently, the maximum amount of RAM that scsi_debug can allocate is
> > 4GB. This patch increases it to 2TB; scsi_debug can allocates 2TB
> > memory and export it as if it were 2TB scsi disk.
> > 
> > Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
> > Cc: Douglas Gilbert <dougg@torque.net>
> > Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
> > ---
> >  drivers/scsi/scsi_debug.c |    6 +++---
> >  1 files changed, 3 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
> > index c98559e..1b6a6d8 100644
> > --- a/drivers/scsi/scsi_debug.c
> > +++ b/drivers/scsi/scsi_debug.c
> > @@ -1949,7 +1949,7 @@ static void __init init_all_queued(void)
> >  }
> >  
> >  static void __init sdebug_build_parts(unsigned char *ramp,
> > -				      unsigned int store_size)
> > +				      unsigned long store_size)
> >  {
> >  	struct partition * pp;
> >  	int starts[SDEBUG_MAX_PARTS + 2];
> > @@ -2476,14 +2476,14 @@ static void do_remove_driverfs_files(void)
> >  
> >  static int __init scsi_debug_init(void)
> >  {
> > -	unsigned int sz;
> > +	unsigned long sz;
> >  	int host_to_add;
> >  	int k;
> >  	int ret;
> >  
> >  	if (scsi_debug_dev_size_mb < 1)
> >  		scsi_debug_dev_size_mb = 1;  /* force minimum 1 MB ramdisk */
> > -	sz = (unsigned int)scsi_debug_dev_size_mb * 1048576;
> > +	sz = (unsigned long)scsi_debug_dev_size_mb * 1048576;
> >  	sdebug_store_sectors = sz / SECT_SIZE;
> >  	sdebug_capacity = get_sdebug_capacity();
> >  
> 
> Tomo,
> Unsigned long is 32 bits on i386 (and 64 bits in the LP64
> data model). Don't you want 64 bits in all cases? Either
> unsigned long long, uint64_t or one of those crappy
> kernel typedefs for 64 bits.

I don't think that u64 is useful.

scsi_debug uses vmalloc for logical unit's contents. so u32 is large
enough for 32-bit systems.

Even if we change scsi_debug use alloc_pages to allocate multiple
pages, 32-bit systems can have only several GB memory at most. So u32
is large enough for them in most cases. The advantage of vmalloc, a
continuous memory area, making the driver simpler a bit, is nice.

vmalloc takes unsigned long so I changed 'unsigned int' to 'unsigned
long' here.

In the end, you need a 64-bit system if you want scsi_debug use huge
amount memory.

Re: [PATCH 0/5] scsi_debug: increase the amount of ram that scsi_ram can allocate

[Douglas Gilbert]

FUJITA Tomonori wrote:
> Currently, the maximum amount of RAM that scsi_debug can actually
> allocate is 4GB. This patchset increase it to 2TB.
> 
> Here's an example, scsi_debug allocates 6GB ram and exports it as if
> it were 6GB disk.
> 
> fujita@rose:/sys/bus/pseudo/drivers/scsi_debug$ cat virtual_gb
> 0
> fujita@rose:/sys/bus/pseudo/drivers/scsi_debug$ cat dev_size_mb
> 6144
> 
> scsi3 : scsi_debug, version 1.81 [20070104], dev_size_mb=6144, opts=0x0
> scsi 3:0:0:0: Direct-Access     Linux    scsi_debug       0004 PQ: 0 ANSI: 5
> sd 3:0:0:0: [sdc] 12582912 512-byte hardware sectors (6442 MB)
> 
> 
> This patchset also include minor cleanup.
> 
> This is against scsi-misc with the scsi_build_sense_buffer helper
> patchset and the scsi_debug lba fix:
> 
> http://marc.info/?l=linux-scsi&m=120640632301595&w=2
> 
> http://marc.info/?l=linux-scsi&m=120643343003171&w=2

For patches 1/5, 2/5, 3/5, 4/5 and 5/5 associated with this post:
Signed-off-by: Douglas Gilbert <dougg@torque.net>


Doug Gilbert