cregit-Linux how code gets into the kernel

Release 4.11 drivers/scsi/ch.c

Directory: drivers/scsi
/*
 * SCSI Media Changer device driver for Linux 2.6
 *
 *     (c) 1996-2003 Gerd Knorr <kraxel@bytesex.org>
 *
 */


#define VERSION "0.25"

#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/compat.h>
#include <linux/chio.h>			/* here are all the ioctls */
#include <linux/mutex.h>
#include <linux/idr.h>
#include <linux/slab.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dbg.h>


#define CH_DT_MAX       16

#define CH_TYPES        8

#define CH_MAX_DEVS     128

MODULE_DESCRIPTION("device driver for scsi media changer devices");
MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org>");
MODULE_LICENSE("GPL");

MODULE_ALIAS_CHARDEV_MAJOR(SCSI_CHANGER_MAJOR);

MODULE_ALIAS_SCSI_DEVICE(TYPE_MEDIUM_CHANGER);

static DEFINE_MUTEX(ch_mutex);

static int init = 1;
module_param(init, int, 0444);
MODULE_PARM_DESC(init, \
    "initialize element status on driver load (default: on)");


static int timeout_move = 300;
module_param(timeout_move, int, 0644);
MODULE_PARM_DESC(timeout_move,"timeout for move commands "
		 "(default: 300 seconds)");


static int timeout_init = 3600;
module_param(timeout_init, int, 0644);
MODULE_PARM_DESC(timeout_init,"timeout for INITIALIZE ELEMENT STATUS "
		 "(default: 3600 seconds)");


static int verbose = 1;
module_param(verbose, int, 0644);
MODULE_PARM_DESC(verbose,"be verbose (default: on)");


static int debug = 0;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug,"enable/disable debug messages, also prints more "
		 "detailed sense codes on scsi errors (default: off)");


static int dt_id[CH_DT_MAX] = { [ 0 ... (CH_DT_MAX-1) ] = -1 };

static int dt_lun[CH_DT_MAX];
module_param_array(dt_id,  int, NULL, 0444);
module_param_array(dt_lun, int, NULL, 0444);

/* tell the driver about vendor-specific slots */

static int vendor_firsts[CH_TYPES-4];

static int vendor_counts[CH_TYPES-4];
module_param_array(vendor_firsts, int, NULL, 0444);
module_param_array(vendor_counts, int, NULL, 0444);


static const char * vendor_labels[CH_TYPES-4] = {
	"v0", "v1", "v2", "v3"
};
// module_param_string_array(vendor_labels, NULL, 0444);


#define ch_printk(prefix, ch, fmt, a...) \
	sdev_prefix_printk(prefix, (ch)->device, (ch)->name, fmt, ##a)


#define DPRINTK(fmt, arg...)						\
do {                                                                    \
        if (debug)                                                      \
                ch_printk(KERN_DEBUG, ch, fmt, ##arg);                  \
} while (0)

#define VPRINTK(level, fmt, arg...)					\
do {                                                                    \
        if (verbose)                                                    \
                ch_printk(level, ch, fmt, ##arg);                       \
} while (0)

/* ------------------------------------------------------------------- */


#define MAX_RETRIES   1


static struct class * ch_sysfs_class;

typedef struct {
	
struct list_head    list;
	
int                 minor;
	
char                name[8];
	
struct scsi_device  *device;
	
struct scsi_device  **dt;        /* ptrs to data transfer elements */
	
u_int               firsts[CH_TYPES];
	
u_int               counts[CH_TYPES];
	
u_int               unit_attention;
	
u_int		    voltags;
	
struct mutex	    lock;
} 
scsi_changer;

static DEFINE_IDR(ch_index_idr);
static DEFINE_SPINLOCK(ch_index_lock);

static const struct {
	
unsigned char  sense;
	
unsigned char  asc;
	
unsigned char  ascq;
	
int	       errno;
} 
ch_err[] = {
/* Just filled in what looks right. Hav'nt checked any standard paper for
   these errno assignments, so they may be wrong... */
	{
		.sense  = ILLEGAL_REQUEST,
		.asc    = 0x21,
		.ascq   = 0x01,
		.errno  = EBADSLT, /* Invalid element address */
	},{
		.sense  = ILLEGAL_REQUEST,
		.asc    = 0x28,
		.ascq   = 0x01,
		.errno  = EBADE,   /* Import or export element accessed */
	},{
		.sense  = ILLEGAL_REQUEST,
		.asc    = 0x3B,
		.ascq   = 0x0D,
		.errno  = EXFULL,  /* Medium destination element full */
	},{
		.sense  = ILLEGAL_REQUEST,
		.asc    = 0x3B,
		.ascq   = 0x0E,
		.errno  = EBADE,   /* Medium source element empty */
	},{
		.sense  = ILLEGAL_REQUEST,
		.asc    = 0x20,
		.ascq   = 0x00,
		.errno  = EBADRQC, /* Invalid command operation code */
	},{
	        /* end of list */
	}
};

/* ------------------------------------------------------------------- */


static int ch_find_errno(struct scsi_sense_hdr *sshdr) { int i,errno = 0; /* Check to see if additional sense information is available */ if (scsi_sense_valid(sshdr) && sshdr->asc != 0) { for (i = 0; ch_err[i].errno != 0; i++) { if (ch_err[i].sense == sshdr->sense_key && ch_err[i].asc == sshdr->asc && ch_err[i].ascq == sshdr->ascq) { errno = -ch_err[i].errno; break; } } } if (errno == 0) errno = -EIO; return errno; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr9279.31%133.33%
James Bottomley1916.38%133.33%
Harvey Harrison54.31%133.33%
Total116100.00%3100.00%


static int ch_do_scsi(scsi_changer *ch, unsigned char *cmd, int cmd_len, void *buffer, unsigned buflength, enum dma_data_direction direction) { int errno, retries = 0, timeout, result; struct scsi_sense_hdr sshdr; timeout = (cmd[0] == INITIALIZE_ELEMENT_STATUS) ? timeout_init : timeout_move; retry: errno = 0; result = scsi_execute_req(ch->device, cmd, direction, buffer, buflength, &sshdr, timeout * HZ, MAX_RETRIES, NULL); if (driver_byte(result) & DRIVER_SENSE) { if (debug) scsi_print_sense_hdr(ch->device, ch->name, &sshdr); errno = ch_find_errno(&sshdr); switch(sshdr.sense_key) { case UNIT_ATTENTION: ch->unit_attention = 1; if (retries++ < 3) goto retry; break; } } return errno; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr12879.50%120.00%
James Bottomley2414.91%120.00%
Hannes Reinecke74.35%240.00%
FUJITA Tomonori21.24%120.00%
Total161100.00%5100.00%

/* ------------------------------------------------------------------------ */
static int ch_elem_to_typecode(scsi_changer *ch, u_int elem) { int i; for (i = 0; i < CH_TYPES; i++) { if (elem >= ch->firsts[i] && elem < ch->firsts[i] + ch->counts[i]) return i+1; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr66100.00%1100.00%
Total66100.00%1100.00%


static int ch_read_element_status(scsi_changer *ch, u_int elem, char *data) { u_char cmd[12]; u_char *buffer; int result; buffer = kmalloc(512, GFP_KERNEL | GFP_DMA); if(!buffer) return -ENOMEM; retry: memset(cmd,0,sizeof(cmd)); cmd[0] = READ_ELEMENT_STATUS; cmd[1] = ((ch->device->lun & 0x7) << 5) | (ch->voltags ? 0x10 : 0) | ch_elem_to_typecode(ch,elem); cmd[2] = (elem >> 8) & 0xff; cmd[3] = elem & 0xff; cmd[5] = 1; cmd[9] = 255; if (0 == (result = ch_do_scsi(ch, cmd, 12, buffer, 256, DMA_FROM_DEVICE))) { if (((buffer[16] << 8) | buffer[17]) != elem) { DPRINTK("asked for element 0x%02x, got 0x%02x\n", elem,(buffer[16] << 8) | buffer[17]); kfree(buffer); return -EIO; } memcpy(data,buffer+16,16); } else { if (ch->voltags) { ch->voltags = 0; VPRINTK(KERN_INFO, "device has no volume tag support\n"); goto retry; } DPRINTK("READ ELEMENT STATUS for element 0x%x failed\n",elem); } kfree(buffer); return result; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr26295.97%125.00%
Hannes Reinecke62.20%250.00%
Joe Perches51.83%125.00%
Total273100.00%4100.00%


static int ch_init_elem(scsi_changer *ch) { int err; u_char cmd[6]; VPRINTK(KERN_INFO, "INITIALIZE ELEMENT STATUS, may take some time ...\n"); memset(cmd,0,sizeof(cmd)); cmd[0] = INITIALIZE_ELEMENT_STATUS; cmd[1] = (ch->device->lun & 0x7) << 5; err = ch_do_scsi(ch, cmd, 6, NULL, 0, DMA_NONE); VPRINTK(KERN_INFO, "... finished\n"); return err; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr7786.52%125.00%
Hannes Reinecke66.74%250.00%
Joe Perches66.74%125.00%
Total89100.00%4100.00%


static int ch_readconfig(scsi_changer *ch) { u_char cmd[10], data[16]; u_char *buffer; int result,id,lun,i; u_int elem; buffer = kzalloc(512, GFP_KERNEL | GFP_DMA); if (!buffer) return -ENOMEM; memset(cmd,0,sizeof(cmd)); cmd[0] = MODE_SENSE; cmd[1] = (ch->device->lun & 0x7) << 5; cmd[2] = 0x1d; cmd[4] = 255; result = ch_do_scsi(ch, cmd, 10, buffer, 255, DMA_FROM_DEVICE); if (0 != result) { cmd[1] |= (1<<3); result = ch_do_scsi(ch, cmd, 10, buffer, 255, DMA_FROM_DEVICE); } if (0 == result) { ch->firsts[CHET_MT] = (buffer[buffer[3]+ 6] << 8) | buffer[buffer[3]+ 7]; ch->counts[CHET_MT] = (buffer[buffer[3]+ 8] << 8) | buffer[buffer[3]+ 9]; ch->firsts[CHET_ST] = (buffer[buffer[3]+10] << 8) | buffer[buffer[3]+11]; ch->counts[CHET_ST] = (buffer[buffer[3]+12] << 8) | buffer[buffer[3]+13]; ch->firsts[CHET_IE] = (buffer[buffer[3]+14] << 8) | buffer[buffer[3]+15]; ch->counts[CHET_IE] = (buffer[buffer[3]+16] << 8) | buffer[buffer[3]+17]; ch->firsts[CHET_DT] = (buffer[buffer[3]+18] << 8) | buffer[buffer[3]+19]; ch->counts[CHET_DT] = (buffer[buffer[3]+20] << 8) | buffer[buffer[3]+21]; VPRINTK(KERN_INFO, "type #1 (mt): 0x%x+%d [medium transport]\n", ch->firsts[CHET_MT], ch->counts[CHET_MT]); VPRINTK(KERN_INFO, "type #2 (st): 0x%x+%d [storage]\n", ch->firsts[CHET_ST], ch->counts[CHET_ST]); VPRINTK(KERN_INFO, "type #3 (ie): 0x%x+%d [import/export]\n", ch->firsts[CHET_IE], ch->counts[CHET_IE]); VPRINTK(KERN_INFO, "type #4 (dt): 0x%x+%d [data transfer]\n", ch->firsts[CHET_DT], ch->counts[CHET_DT]); } else { VPRINTK(KERN_INFO, "reading element address assignment page failed!\n"); } /* vendor specific element types */ for (i = 0; i < 4; i++) { if (0 == vendor_counts[i]) continue; if (NULL == vendor_labels[i]) continue; ch->firsts[CHET_V1+i] = vendor_firsts[i]; ch->counts[CHET_V1+i] = vendor_counts[i]; VPRINTK(KERN_INFO, "type #%d (v%d): 0x%x+%d [%s, vendor specific]\n", i+5,i+1,vendor_firsts[i],vendor_counts[i], vendor_labels[i]); } /* look up the devices of the data transfer elements */ ch->dt = kcalloc(ch->counts[CHET_DT], sizeof(*ch->dt), GFP_KERNEL); if (!ch->dt) { kfree(buffer); return -ENOMEM; } for (elem = 0; elem < ch->counts[CHET_DT]; elem++) { id = -1; lun = 0; if (elem < CH_DT_MAX && -1 != dt_id[elem]) { id = dt_id[elem]; lun = dt_lun[elem]; VPRINTK(KERN_INFO, "dt 0x%x: [insmod option] ", elem+ch->firsts[CHET_DT]); } else if (0 != ch_read_element_status (ch,elem+ch->firsts[CHET_DT],data)) { VPRINTK(KERN_INFO, "dt 0x%x: READ ELEMENT STATUS failed\n", elem+ch->firsts[CHET_DT]); } else { VPRINTK(KERN_INFO, "dt 0x%x: ",elem+ch->firsts[CHET_DT]); if (data[6] & 0x80) { VPRINTK(KERN_CONT, "not this SCSI bus\n"); ch->dt[elem] = NULL; } else if (0 == (data[6] & 0x30)) { VPRINTK(KERN_CONT, "ID/LUN unknown\n"); ch->dt[elem] = NULL; } else { id = ch->device->id; lun = 0; if (data[6] & 0x20) id = data[7]; if (data[6] & 0x10) lun = data[6] & 7; } } if (-1 != id) { VPRINTK(KERN_CONT, "ID %i, LUN %i, ",id,lun); ch->dt[elem] = scsi_device_lookup(ch->device->host, ch->device->channel, id,lun); if (!ch->dt[elem]) { /* should not happen */ VPRINTK(KERN_CONT, "Huh? device not found!\n"); } else { VPRINTK(KERN_CONT, "name: %8.8s %16.16s %4.4s\n", ch->dt[elem]->vendor, ch->dt[elem]->model, ch->dt[elem]->rev); } } } ch->voltags = 1; kfree(buffer); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr92992.44%112.50%
Joe Perches424.18%112.50%
Davidlohr Bueso A181.79%112.50%
Hannes Reinecke80.80%225.00%
Julia Lawall60.60%112.50%
Masanari Iida10.10%112.50%
Vignesh Babu10.10%112.50%
Total1005100.00%8100.00%

/* ------------------------------------------------------------------------ */
static int ch_position(scsi_changer *ch, u_int trans, u_int elem, int rotate) { u_char cmd[10]; DPRINTK("position: 0x%x\n",elem); if (0 == trans) trans = ch->firsts[CHET_MT]; memset(cmd,0,sizeof(cmd)); cmd[0] = POSITION_TO_ELEMENT; cmd[1] = (ch->device->lun & 0x7) << 5; cmd[2] = (trans >> 8) & 0xff; cmd[3] = trans & 0xff; cmd[4] = (elem >> 8) & 0xff; cmd[5] = elem & 0xff; cmd[8] = rotate ? 1 : 0; return ch_do_scsi(ch, cmd, 10, NULL, 0, DMA_NONE); }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr14795.45%125.00%
Hannes Reinecke63.90%250.00%
Joe Perches10.65%125.00%
Total154100.00%4100.00%


static int ch_move(scsi_changer *ch, u_int trans, u_int src, u_int dest, int rotate) { u_char cmd[12]; DPRINTK("move: 0x%x => 0x%x\n",src,dest); if (0 == trans) trans = ch->firsts[CHET_MT]; memset(cmd,0,sizeof(cmd)); cmd[0] = MOVE_MEDIUM; cmd[1] = (ch->device->lun & 0x7) << 5; cmd[2] = (trans >> 8) & 0xff; cmd[3] = trans & 0xff; cmd[4] = (src >> 8) & 0xff; cmd[5] = src & 0xff; cmd[6] = (dest >> 8) & 0xff; cmd[7] = dest & 0xff; cmd[10] = rotate ? 1 : 0; return ch_do_scsi(ch, cmd, 12, NULL,0, DMA_NONE); }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr17496.13%125.00%
Hannes Reinecke63.31%250.00%
Joe Perches10.55%125.00%
Total181100.00%4100.00%


static int ch_exchange(scsi_changer *ch, u_int trans, u_int src, u_int dest1, u_int dest2, int rotate1, int rotate2) { u_char cmd[12]; DPRINTK("exchange: 0x%x => 0x%x => 0x%x\n", src,dest1,dest2); if (0 == trans) trans = ch->firsts[CHET_MT]; memset(cmd,0,sizeof(cmd)); cmd[0] = EXCHANGE_MEDIUM; cmd[1] = (ch->device->lun & 0x7) << 5; cmd[2] = (trans >> 8) & 0xff; cmd[3] = trans & 0xff; cmd[4] = (src >> 8) & 0xff; cmd[5] = src & 0xff; cmd[6] = (dest1 >> 8) & 0xff; cmd[7] = dest1 & 0xff; cmd[8] = (dest2 >> 8) & 0xff; cmd[9] = dest2 & 0xff; cmd[10] = (rotate1 ? 1 : 0) | (rotate2 ? 2 : 0); return ch_do_scsi(ch, cmd, 12, NULL, 0, DMA_NONE); }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr21496.83%125.00%
Hannes Reinecke62.71%250.00%
Joe Perches10.45%125.00%
Total221100.00%4100.00%


static void ch_check_voltag(char *tag) { int i; for (i = 0; i < 32; i++) { /* restrict to ascii */ if (tag[i] >= 0x7f || tag[i] < 0x20) tag[i] = ' '; /* don't allow search wildcards */ if (tag[i] == '?' || tag[i] == '*') tag[i] = ' '; } }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr76100.00%1100.00%
Total76100.00%1100.00%


static int ch_set_voltag(scsi_changer *ch, u_int elem, int alternate, int clear, u_char *tag) { u_char cmd[12]; u_char *buffer; int result; buffer = kzalloc(512, GFP_KERNEL); if (!buffer) return -ENOMEM; DPRINTK("%s %s voltag: 0x%x => \"%s\"\n", clear ? "clear" : "set", alternate ? "alternate" : "primary", elem, tag); memset(cmd,0,sizeof(cmd)); cmd[0] = SEND_VOLUME_TAG; cmd[1] = ((ch->device->lun & 0x7) << 5) | ch_elem_to_typecode(ch,elem); cmd[2] = (elem >> 8) & 0xff; cmd[3] = elem & 0xff; cmd[5] = clear ? (alternate ? 0x0d : 0x0c) : (alternate ? 0x0b : 0x0a); cmd[9] = 255; memcpy(buffer,tag,32); ch_check_voltag(buffer); result = ch_do_scsi(ch, cmd, 12, buffer, 256, DMA_TO_DEVICE); kfree(buffer); return result; }

Contributors

PersonTokensPropCommitsCommitProp
Gerd Knorr20396.21%120.00%
Hannes Reinecke62.84%240.00%
Vignesh Babu10.47%120.00%
Joe Perches10.47%120.00%
Total211100.00%5100.00%


static int ch_gstatus(scsi_changer *ch, int type, unsigned char __user *dest) { int retval = 0; u_char data[16]; unsigned int i; mutex_lock(