[PATCH 4/5] scsi: 53c700: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

From: Lee Jones
Date: Thu Jan 11 2024 - 08:18:48 EST


Since snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
something else instead in order to avoid confusion.

In the case of sysfs call-backs, new wrappers exist that do just that.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Richard Hirst <rhirst@xxxxxxxxxxxxx>
Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
---
drivers/scsi/53c700.c | 104 +++++++++++++++++++++---------------------
1 file changed, 52 insertions(+), 52 deletions(-)

diff --git a/drivers/scsi/53c700.c b/drivers/scsi/53c700.c
index 857be0f3ae5b9..1aa933485719a 100644
--- a/drivers/scsi/53c700.c
+++ b/drivers/scsi/53c700.c
@@ -4,7 +4,7 @@
*
* Copyright (C) 2001 by James.Bottomley@xxxxxxxxxxxxxxxxxxxxx
**-----------------------------------------------------------------------------
-**
+**
**
**-----------------------------------------------------------------------------
*/
@@ -18,7 +18,7 @@
*
* The 700 is the lowliest of the line, it can only do async SCSI.
* The 700-66 can at least do synchronous SCSI up to 10MHz.
- *
+ *
* The 700 chip has no host bus interface logic of its own. However,
* it is usually mapped to a location with well defined register
* offsets. Therefore, if you can determine the base address and the
@@ -61,7 +61,7 @@
* consistent memory allocation.
*
* Version 2.5
- *
+ *
* More Compatibility changes for 710 (now actually works). Enhanced
* support for odd clock speeds which constrain SDTR negotiations.
* correct cacheline separation for scsi messages and status for
@@ -70,7 +70,7 @@
*
* Version 2.4
*
- * Added support for the 53c710 chip (in 53c700 emulation mode only---no
+ * Added support for the 53c710 chip (in 53c700 emulation mode only---no
* special 53c710 instructions or registers are used).
*
* Version 2.3
@@ -190,7 +190,7 @@ static char *NCR_700_condition[] = {
"DISCONNECT_MSG RECEIVED",
"MSG_OUT",
"DATA_IN",
-
+
};

static char *NCR_700_fatal_messages[] = {
@@ -260,7 +260,7 @@ NCR_700_offset_period_to_sxfer(struct NCR_700_Host_Parameters *hostdata,
static inline __u8
NCR_700_get_SXFER(struct scsi_device *SDp)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SDp->host->hostdata[0];

return NCR_700_offset_period_to_sxfer(hostdata,
@@ -416,7 +416,7 @@ NCR_700_detect(struct scsi_host_template *tpnt,
int
NCR_700_release(struct Scsi_Host *host)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)host->hostdata[0];

if (hostdata->noncoherent)
@@ -449,7 +449,7 @@ NCR_700_identify(int can_disconnect, __u8 lun)
* Inputs : host - SCSI host */
static inline int
NCR_700_data_residual (struct Scsi_Host *host) {
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)host->hostdata[0];
int count, synchronous = 0;
unsigned int ddir;
@@ -461,16 +461,16 @@ NCR_700_data_residual (struct Scsi_Host *host) {
count = ((NCR_700_readb(host, DFIFO_REG) & 0x3f) -
(NCR_700_readl(host, DBC_REG) & 0x3f)) & 0x3f;
}
-
+
if(hostdata->fast)
synchronous = NCR_700_readb(host, SXFER_REG) & 0x0f;
-
+
/* get the data direction */
ddir = NCR_700_readb(host, CTEST0_REG) & 0x01;

if (ddir) {
/* Receive */
- if (synchronous)
+ if (synchronous)
count += (NCR_700_readb(host, SSTAT2_REG) & 0xf0) >> 4;
else
if (NCR_700_readb(host, SSTAT1_REG) & SIDL_REG_FULL)
@@ -500,7 +500,7 @@ sbcl_to_string(__u8 sbcl)

ret[0]='\0';
for(i=0; i<8; i++) {
- if((1<<i) & sbcl)
+ if((1<<i) & sbcl)
strcat(ret, NCR_700_SBCL_bits[i]);
}
strcat(ret, NCR_700_SBCL_to_phase[sbcl & 0x07]);
@@ -533,7 +533,7 @@ find_empty_slot(struct NCR_700_Host_Parameters *hostdata)
if(slot->state != NCR_700_SLOT_FREE)
/* should panic! */
printk(KERN_ERR "BUSY SLOT ON FREE LIST!!!\n");
-
+

hostdata->free_list = slot->ITL_forw;
slot->ITL_forw = NULL;
@@ -546,11 +546,11 @@ find_empty_slot(struct NCR_700_Host_Parameters *hostdata)
slot->state = NCR_700_SLOT_BUSY;
slot->flags = 0;
hostdata->command_slot_count++;
-
+
return slot;
}

-STATIC void
+STATIC void
free_slot(struct NCR_700_command_slot *slot,
struct NCR_700_Host_Parameters *hostdata)
{
@@ -560,7 +560,7 @@ free_slot(struct NCR_700_command_slot *slot,
if(slot->state == NCR_700_SLOT_FREE) {
printk(KERN_ERR "53c700: SLOT %p is FREE!!!\n", slot);
}
-
+
slot->resume_offset = 0;
slot->cmnd = NULL;
slot->state = NCR_700_SLOT_FREE;
@@ -654,7 +654,7 @@ NCR_700_internal_bus_reset(struct Scsi_Host *host)
STATIC void
NCR_700_chip_setup(struct Scsi_Host *host)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)host->hostdata[0];
__u8 min_period;
__u8 min_xferp = (hostdata->chip710 ? NCR_710_MIN_XFERP : NCR_700_MIN_XFERP);
@@ -694,11 +694,11 @@ NCR_700_chip_setup(struct Scsi_Host *host)
} else {
NCR_700_writeb(BURST_LENGTH_8 | hostdata->dmode_extra,
host, DMODE_700_REG);
- NCR_700_writeb(hostdata->differential ?
+ NCR_700_writeb(hostdata->differential ?
DIFF : 0, host, CTEST7_REG);
if(hostdata->fast) {
/* this is for 700-66, does nothing on 700 */
- NCR_700_writeb(LAST_DIS_ENBL | ENABLE_ACTIVE_NEGATION
+ NCR_700_writeb(LAST_DIS_ENBL | ENABLE_ACTIVE_NEGATION
| GENERATE_RECEIVE_PARITY, host,
CTEST8_REG);
} else {
@@ -731,7 +731,7 @@ NCR_700_chip_setup(struct Scsi_Host *host)
NCR_700_writeb(ASYNC_DIV_3_0 | hostdata->dcntl_extra, host, DCNTL_REG);
hostdata->sync_clock = hostdata->clock*2;
hostdata->sync_clock /= 3;
-
+
} else if(hostdata->clock > 37 && hostdata->clock <= 50) {
/* sync divider 1, async divider 2 */
DEBUG(("53c700: sync 1 async 2\n"));
@@ -764,7 +764,7 @@ NCR_700_chip_setup(struct Scsi_Host *host)
STATIC void
NCR_700_chip_reset(struct Scsi_Host *host)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)host->hostdata[0];
if(hostdata->chip710) {
NCR_700_writeb(SOFTWARE_RESET_710, host, ISTAT_REG);
@@ -774,7 +774,7 @@ NCR_700_chip_reset(struct Scsi_Host *host)
} else {
NCR_700_writeb(SOFTWARE_RESET, host, DCNTL_REG);
udelay(100);
-
+
NCR_700_writeb(0, host, DCNTL_REG);
}

@@ -790,7 +790,7 @@ NCR_700_chip_reset(struct Scsi_Host *host)
* ACK) so that the routine returns correctly to resume its activity
* */
STATIC __u32
-process_extended_message(struct Scsi_Host *host,
+process_extended_message(struct Scsi_Host *host,
struct NCR_700_Host_Parameters *hostdata,
struct scsi_cmnd *SCp, __u32 dsp, __u32 dsps)
{
@@ -816,15 +816,15 @@ process_extended_message(struct Scsi_Host *host,

spi_offset(starget) = offset;
spi_period(starget) = period;
-
+
if(NCR_700_is_flag_set(SCp->device, NCR_700_DEV_PRINT_SYNC_NEGOTIATION)) {
spi_display_xfer_agreement(starget);
NCR_700_clear_flag(SCp->device, NCR_700_DEV_PRINT_SYNC_NEGOTIATION);
}
-
+
NCR_700_set_flag(SCp->device, NCR_700_DEV_NEGOTIATED_SYNC);
NCR_700_clear_flag(SCp->device, NCR_700_DEV_BEGIN_SYNC_NEGOTIATION);
-
+
NCR_700_writeb(NCR_700_get_SXFER(SCp->device),
host, SXFER_REG);

@@ -841,7 +841,7 @@ process_extended_message(struct Scsi_Host *host,
resume_offset = hostdata->pScript + Ent_SendMessageWithATN;
}
break;
-
+
case A_WDTR_MSG:
printk(KERN_INFO "scsi%d: (%d:%d), Unsolicited WDTR after CMD, Rejecting\n",
host->host_no, pun, lun);
@@ -1121,7 +1121,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,

SCp = scsi_host_find_tag(SDp->host, hostdata->msgin[2]);
if(unlikely(SCp == NULL)) {
- printk(KERN_ERR "scsi%d: (%d:%d) no saved request for tag %d\n",
+ printk(KERN_ERR "scsi%d: (%d:%d) no saved request for tag %d\n",
host->host_no, reselection_id, lun, hostdata->msgin[2]);
BUG();
}
@@ -1180,7 +1180,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
slot->cmnd->cmd_len);


-
+
}
} else if(dsps == A_RESELECTED_DURING_SELECTION) {

@@ -1193,10 +1193,10 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,

__u8 reselection_id = NCR_700_readb(host, SFBR_REG);
struct NCR_700_command_slot *slot;
-
+
/* Take out our own ID */
reselection_id &= ~(1<<host->this_id);
-
+
/* I've never seen this happen, so keep this as a printk rather
* than a debug */
printk(KERN_INFO "scsi%d: (%d:%d) RESELECTION DURING SELECTION, dsp=%08x[%04x] state=%d, count=%d\n",
@@ -1222,7 +1222,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
slot->state = NCR_700_SLOT_QUEUED;
}
hostdata->cmd = NULL;
-
+
if(reselection_id == 0) {
if(hostdata->reselection_id == 0xff) {
printk(KERN_ERR "scsi%d: Invalid reselection during selection!!\n", host->host_no);
@@ -1233,7 +1233,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
reselection_id = hostdata->reselection_id;
}
} else {
-
+
/* convert to real ID */
reselection_id = bitmap_to_number(reselection_id);
}
@@ -1251,7 +1251,7 @@ process_script_interrupt(__u32 dsps, __u32 dsp, struct scsi_cmnd *SCp,
* a return here will re-run the queued command slot
* that may have been interrupted by the initial selection */
DEBUG((" SELECTION COMPLETED\n"));
- } else if((dsps & 0xfffff0f0) == A_MSG_IN) {
+ } else if((dsps & 0xfffff0f0) == A_MSG_IN) {
resume_offset = process_message(host, hostdata, SCp,
dsp, dsps);
} else if((dsps & 0xfffff000) == 0) {
@@ -1304,7 +1304,7 @@ process_selection(struct Scsi_Host *host, __u32 dsp)

/* Take out our own ID */
id &= ~(1<<host->this_id);
- if(id != 0)
+ if(id != 0)
break;
udelay(5);
}
@@ -1322,7 +1322,7 @@ process_selection(struct Scsi_Host *host, __u32 dsp)
struct NCR_700_command_slot *slot =
(struct NCR_700_command_slot *)SCp->host_scribble;
DEBUG((" ID %d WARNING: RESELECTION OF BUSY HOST, saving cmd %p, slot %p, addr %x [%04x], resume %x!\n", id, hostdata->cmd, slot, dsp, dsp - hostdata->pScript, resume_offset));
-
+
switch(dsp - hostdata->pScript) {
case Ent_Disconnect1:
case Ent_Disconnect2:
@@ -1344,7 +1344,7 @@ process_selection(struct Scsi_Host *host, __u32 dsp)
case Ent_Finish2:
process_script_interrupt(A_GOOD_STATUS_AFTER_STATUS, dsp, SCp, host, hostdata);
break;
-
+
default:
slot->state = NCR_700_SLOT_QUEUED;
break;
@@ -1547,7 +1547,7 @@ NCR_700_intr(int irq, void *dev_id)
/* clear all the negotiated parameters */
__shost_for_each_device(SDp, host)
NCR_700_clear_flag(SDp, ~0);
-
+
/* clear all the slots and their pending commands */
for(i = 0; i < NCR_700_COMMAND_SLOTS_PER_HOST; i++) {
struct scsi_cmnd *SCp;
@@ -1556,7 +1556,7 @@ NCR_700_intr(int irq, void *dev_id)

if(slot->state == NCR_700_SLOT_FREE)
continue;
-
+
SCp = slot->cmnd;
printk(KERN_ERR " failing command because of reset, slot %p, cmnd %p\n",
slot, SCp);
@@ -1620,7 +1620,7 @@ NCR_700_intr(int irq, void *dev_id)
data_transfer += residual;

if(data_transfer != 0) {
- int count;
+ int count;
__u32 pAddr;

SGcount--;
@@ -1680,7 +1680,7 @@ NCR_700_intr(int irq, void *dev_id)
NCR_700_scsi_done(hostdata, SCp, DID_ERROR<<16);
}

-
+
/* NOTE: selection interrupt processing MUST occur
* after script interrupt processing to correctly cope
* with the case where we process a disconnect and
@@ -1718,7 +1718,7 @@ NCR_700_intr(int irq, void *dev_id)
DEBUG(("Attempting to resume at %x\n", resume_offset));
NCR_700_clear_fifo(host);
NCR_700_writel(resume_offset, host, DSP_REG);
- }
+ }
/* There is probably a technical no-no about this: If we're a
* shared interrupt and we got this interrupt because the
* other device needs servicing not us, we're still going to
@@ -1732,7 +1732,7 @@ NCR_700_intr(int irq, void *dev_id)
* position we left off */
int j = (i + hostdata->saved_slot_position)
% NCR_700_COMMAND_SLOTS_PER_HOST;
-
+
if(hostdata->slots[j].state != NCR_700_SLOT_QUEUED)
continue;
if(NCR_700_start_command(hostdata->slots[j].cmnd)) {
@@ -1752,7 +1752,7 @@ NCR_700_intr(int irq, void *dev_id)

static int NCR_700_queuecommand_lck(struct scsi_cmnd *SCp)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SCp->device->host->hostdata[0];
__u32 move_ins;
struct NCR_700_command_slot *slot;
@@ -1852,7 +1852,7 @@ static int NCR_700_queuecommand_lck(struct scsi_cmnd *SCp)
default:
printk(KERN_ERR "53c700: Unknown command for data direction ");
scsi_print_command(SCp);
-
+
move_ins = 0;
break;
case DMA_NONE:
@@ -1937,7 +1937,7 @@ STATIC int
NCR_700_host_reset(struct scsi_cmnd * SCp)
{
DECLARE_COMPLETION_ONSTACK(complete);
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SCp->device->host->hostdata[0];

scmd_printk(KERN_INFO, SCp,
@@ -1975,9 +1975,9 @@ STATIC void
NCR_700_set_period(struct scsi_target *STp, int period)
{
struct Scsi_Host *SHp = dev_to_shost(STp->dev.parent);
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SHp->hostdata[0];
-
+
if(!hostdata->fast)
return;

@@ -1994,11 +1994,11 @@ STATIC void
NCR_700_set_offset(struct scsi_target *STp, int offset)
{
struct Scsi_Host *SHp = dev_to_shost(STp->dev.parent);
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SHp->hostdata[0];
int max_offset = hostdata->chip710
? NCR_710_MAX_OFFSET : NCR_700_MAX_OFFSET;
-
+
if(!hostdata->fast)
return;

@@ -2031,7 +2031,7 @@ NCR_700_slave_alloc(struct scsi_device *SDp)
STATIC int
NCR_700_slave_configure(struct scsi_device *SDp)
{
- struct NCR_700_Host_Parameters *hostdata =
+ struct NCR_700_Host_Parameters *hostdata =
(struct NCR_700_Host_Parameters *)SDp->host->hostdata[0];

/* to do here: allocate memory; build a queue_full list */
@@ -2071,7 +2071,7 @@ NCR_700_show_active_tags(struct device *dev, struct device_attribute *attr, char
{
struct scsi_device *SDp = to_scsi_device(dev);

- return snprintf(buf, 20, "%d\n", NCR_700_get_depth(SDp));
+ return sysfs_emit(buf, "%d\n", NCR_700_get_depth(SDp));
}

static struct device_attribute NCR_700_active_tags_attr = {
--
2.43.0.275.g3460e3d667-goog