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* History:
* Started: Aug 9 by Lawrence Foard (entropy@world.std.com),
* to allow user process control of SCSI devices.
* Development Sponsored by Killy Corp. NY NY
*
* Original driver (sg.c):
* Copyright (C) 1992 Lawrence Foard
* 2.x extensions to driver:
* Copyright (C) 1998, 1999 Douglas Gilbert
*
* 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.
*
* Borrows code from st driver. Thanks to Alessandro Rubini's "dd" book.
*/
static char * sg_version_str = "Version: 2.1.34 (990603)";
static int sg_version_num = 20134; /* 2 digits for each component */
/*
* D. P. Gilbert (dgilbert@interlog.com, dougg@triode.net.au), notes:
* - scsi logging is available via SCSI_LOG_TIMEOUT macros. First
* the kernel/module needs to be built with CONFIG_SCSI_LOGGING
* (otherwise the macros compile to empty statements), then do
* something like: 'echo "scsi log all" > /proc/scsi/scsi' to log
* everything or 'echo "scsi log {token} #N" > /proc/scsi/scsi'
* where {token} is one of [error,timeout,scan,mlqueue,mlcomplete,
* llqueue,llcomplete,hlqueue,hlcomplete,ioctl] and #N is 0...7
* (with 0 meaning off). For example: 'scsi log timeout 7 >
* /proc/scsi/scsi' to get all logging messages from this driver.
* Should use hlcomplete but it is too "noisy" (sd uses it).
*
* - This driver obtains memory (heap) for the low-level driver to
* transfer/dma to and from. It is obtained from up to 3 sources:
* - obtain heap via get_free_pages()
* - obtain heap from the shared scsi dma pool
* - obtain heap from kernel directly (kmalloc) [last choice]
* Each open() attempts to obtain a "reserve" buffer of
* SG_DEF_RESERVED_SIZE bytes (or 0 bytes if opened O_RDONLY). The
* amount actually obtained [which could be 0 bytes] can be found from
* the SG_GET_RESERVED_SIZE ioctl(). This reserved buffer size can
* be changed by calling the SG_SET_RESERVED_SIZE ioctl(). Since this
* is an ambit claim, it should be followed by a SG_GET_RESERVED_SIZE
* ioctl() to find out how much was actually obtained.
* A subsequent write() to this file descriptor will use the
* reserved buffer unless:
* - it is already in use (eg during command queuing)
* - or the write() needs a buffer size larger than the
* reserved size
* In these cases the write() will attempt to get the required memory
* for the duration of this request but, if memory is low, it may
* fail with ENOMEM.
*
* - The 'alt_address' field in the scatter_list structure and the
* related 'mem_src' indicate the source of the heap allocation.
*
*/
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/mtio.h>
#include <linux/ioctl.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/blk.h>
#include "scsi.h"
#include "hosts.h"
#include <scsi/scsi_ioctl.h>
#include <scsi/sg.h>
int sg_big_buff = SG_DEF_RESERVED_SIZE; /* sg_big_buff is ro through sysctl */
/* N.B. This global is here to keep existing software happy. It now holds
the size of the reserve buffer of the most recent sucessful sg_open().
Only available when 'sg' compiled into kernel (rather than a module).
This is deprecated (use SG_GET_RESERVED_SIZE ioctl() instead). */
#define SG_SECTOR_SZ 512
#define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
#define SG_LOW_POOL_THRESHHOLD 30
#define SG_MAX_POOL_SECTORS 320 /* Max. number of pool sectors to take */
static int sg_pool_secs_avail = SG_MAX_POOL_SECTORS;
/* #define SG_DEBUG */ /* for counting varieties of allocations */
#ifdef SG_DEBUG
static int sg_num_kmal = 0;
static int sg_num_pool = 0;
static int sg_num_page = 0;
#endif
#define SG_HEAP_PAGE 1 /* heap from kernel via get_free_pages() */
#define SG_HEAP_KMAL 2 /* heap from kernel via kmalloc() */
#define SG_HEAP_POOL 3 /* heap from scsi dma pool (mid-level) */
static int sg_init(void);
static int sg_attach(Scsi_Device *);
static void sg_finish(void);
static int sg_detect(Scsi_Device *);
static void sg_detach(Scsi_Device *);
struct Scsi_Device_Template sg_template = {NULL, NULL, "sg", NULL, 0xff,
SCSI_GENERIC_MAJOR, 0, 0, 0, 0,
sg_detect, sg_init,
sg_finish, sg_attach, sg_detach};
typedef struct sg_scatter_hold /* holding area for scsi scatter gather info */
{
unsigned short use_sg; /* Number of pieces of scatter-gather */
unsigned short sglist_len; /* size of malloc'd scatter-gather list */
unsigned bufflen; /* Size of (aggregate) data buffer */
unsigned b_malloc_len; /* actual len malloc'ed in buffer */
void * buffer; /* Data buffer or scatter list,12 bytes each*/
char mem_src; /* heap whereabouts of 'buffer' */
} Sg_scatter_hold; /* 20 bytes long on i386 */
struct sg_device; /* forward declarations */
struct sg_fd;
typedef struct sg_request /* SG_MAX_QUEUE requests outstanding per file */
{
Scsi_Cmnd * my_cmdp; /* NULL -> ready to read, else id */
struct sg_request * nextrp; /* NULL -> tail request (slist) */
struct sg_fd * parentfp; /* NULL -> not in use */
Sg_scatter_hold data; /* hold buffer, perhaps scatter list */
struct sg_header header; /* scsi command+info, see <scsi/sg.h> */
char res_used; /* 1 -> using reserve buffer, 0 -> not ... */
} Sg_request; /* 72 bytes long on i386 */
typedef struct sg_fd /* holds the state of a file descriptor */
{
struct sg_fd * nextfp; /* NULL when last opened fd on this device */
struct sg_device * parentdp; /* owning device */
wait_queue_head_t read_wait; /* queue read until command done */
int timeout; /* defaults to SG_DEFAULT_TIMEOUT */
Sg_scatter_hold reserve; /* buffer held for this file descriptor */
unsigned save_scat_len; /* original length of trunc. scat. element */
Sg_request * headrp; /* head of request slist, NULL->empty */
struct fasync_struct * async_qp; /* used by asynchronous notification */
Sg_request req_arr[SG_MAX_QUEUE]; /* used as singly-linked list */
char low_dma; /* as in parent but possibly overridden to 1 */
char force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */
char closed; /* 1 -> fd closed but request(s) outstanding */
char my_mem_src; /* heap whereabouts of this Sg_fd object */
char cmd_q; /* 1 -> allow command queuing, 0 -> don't */
char underrun_flag; /* 1 -> flag underruns, 0 -> don't, 2 -> test */
char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */
} Sg_fd; /* 1208 bytes long on i386 */
typedef struct sg_device /* holds the state of each scsi generic device */
{
Scsi_Device * device;
wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
int sg_tablesize; /* adapter's max scatter-gather table size */
Sg_fd * headfp; /* first open fd belonging to this device */
kdev_t i_rdev; /* holds device major+minor number */
char exclude; /* opened for exclusive access */
char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
unsigned char merge_fd; /* 0->sequencing per fd, else fd count */
} Sg_device; /* 24 bytes long on i386 */
static int sg_fasync(int fd, struct file * filp, int mode);
static void sg_command_done(Scsi_Cmnd * SCpnt);
static int sg_start_req(Sg_request * srp, int max_buff_size,
const char * inp, int num_write_xfer);
static void sg_finish_rem_req(Sg_request * srp, char * outp,
int num_read_xfer);
static int sg_build_scat(Sg_scatter_hold * schp, int buff_size,
const Sg_fd * sfp);
static void sg_write_xfer(Sg_scatter_hold * schp, const char * inp,
int num_write_xfer);
static void sg_remove_scat(Sg_scatter_hold * schp);
static void sg_read_xfer(Sg_scatter_hold * schp, char * outp,
int num_read_xfer);
static void sg_build_reserve(Sg_fd * sfp, int req_size);
static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size);
static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
static char * sg_malloc(const Sg_fd * sfp, int size, int * retSzp,
int * mem_srcp);
static void sg_free(char * buff, int size, int mem_src);
static char * sg_low_malloc(int rqSz, int lowDma, int mem_src,
int * retSzp);
static void sg_low_free(char * buff, int size, int mem_src);
static Sg_fd * sg_add_sfp(Sg_device * sdp, int dev, int get_reserved);
static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static Sg_request * sg_get_request(const Sg_fd * sfp, int pack_id);
static Sg_request * sg_add_request(Sg_fd * sfp);
static int sg_remove_request(Sg_fd * sfp, const Sg_request * srp);
static int sg_res_in_use(const Sg_fd * sfp);
static void sg_clr_scpnt(Scsi_Cmnd * SCpnt);
static void sg_shorten_timeout(Scsi_Cmnd * scpnt);
static void sg_debug(const Sg_device * sdp, const Sg_fd * sfp, int part_of);
static void sg_debug_all(const Sg_fd * sfp);
static Sg_device * sg_dev_arr = NULL;
static const int size_sg_header = sizeof(struct sg_header);
static int sg_open(struct inode * inode, struct file * filp)
{
int dev = MINOR(inode->i_rdev);
int flags = filp->f_flags;
Sg_device * sdp;
Sg_fd * sfp;
int res;
if ((NULL == sg_dev_arr) || (dev < 0) || (dev >= sg_template.dev_max))
return -ENXIO;
sdp = &sg_dev_arr[dev];
if ((! sdp->device) || (! sdp->device->host))
return -ENXIO;
if (sdp->i_rdev != inode->i_rdev)
printk("sg_open: inode maj=%d, min=%d sdp maj=%d, min=%d\n",
MAJOR(inode->i_rdev), MINOR(inode->i_rdev),
MAJOR(sdp->i_rdev), MINOR(sdp->i_rdev));
/* If we are in the middle of error recovery, don't let anyone
* else try and use this device. Also, if error recovery fails, it
* may try and take the device offline, in which case all further
* access to the device is prohibited. */
if(! scsi_block_when_processing_errors(sdp->device))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
if (flags & O_EXCL) {
if (O_RDONLY == (flags & O_ACCMODE))
return -EACCES; /* Can't lock it with read only access */
if (sdp->headfp && (filp->f_flags & O_NONBLOCK))
return -EBUSY;
res = 0; /* following is a macro that beats race condition */
__wait_event_interruptible(sdp->o_excl_wait,
((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)),
res);
if (res)
return res; /* -ERESTARTSYS because signal hit process */
}
else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */
if (filp->f_flags & O_NONBLOCK)
return -EBUSY;
res = 0; /* following is a macro that beats race condition */
__wait_event_interruptible(sdp->o_excl_wait, (! sdp->exclude), res);
if (res)
return res; /* -ERESTARTSYS because signal hit process */
}
if (! sdp->headfp) { /* no existing opens on this device */
sdp->sgdebug = 0;
sdp->sg_tablesize = sdp->device->host->sg_tablesize;
sdp->merge_fd = 0; /* A little tricky if SG_DEF_MERGE_FD set */
}
if ((sfp = sg_add_sfp(sdp, dev, O_RDWR == (flags & O_ACCMODE)))) {
filp->private_data = sfp;
#if SG_DEF_MERGE_FD
if (0 == sdp->merge_fd)
sdp->merge_fd = 1;
#endif
}
else {
if (flags & O_EXCL) sdp->exclude = 0; /* undo if error */
return -ENOMEM;
}
if (sdp->device->host->hostt->module)
__MOD_INC_USE_COUNT(sdp->device->host->hostt->module);
if (sg_template.module)
__MOD_INC_USE_COUNT(sg_template.module);
return 0;
}
/* Following function was formerly called 'sg_close' */
static int sg_release(struct inode * inode, struct file * filp)
{
Sg_device * sdp;
Sg_fd * sfp;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_release: dev=%d\n", MINOR(sdp->i_rdev)));
sg_fasync(-1, filp, 0); /* remove filp from async notification list */
sg_remove_sfp(sdp, sfp);
if (! sdp->headfp) {
filp->private_data = NULL;
sdp->merge_fd = 0;
}
if (sdp->device->host->hostt->module)
__MOD_DEC_USE_COUNT(sdp->device->host->hostt->module);
if(sg_template.module)
__MOD_DEC_USE_COUNT(sg_template.module);
sdp->exclude = 0;
wake_up_interruptible(&sdp->o_excl_wait);
return 0;
}
static ssize_t sg_read(struct file * filp, char * buf,
size_t count, loff_t *ppos)
{
int k, res;
Sg_device * sdp;
Sg_fd * sfp;
Sg_request * srp;
int req_pack_id = -1;
struct sg_header * shp = (struct sg_header *)buf;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_read: dev=%d, count=%d\n",
MINOR(sdp->i_rdev), (int)count));
if(! scsi_block_when_processing_errors(sdp->device))
return -ENXIO;
if (ppos != &filp->f_pos)
; /* FIXME: Hmm. Seek to the right place, or fail? */
if ((k = verify_area(VERIFY_WRITE, buf, count)))
return k;
if (sfp->force_packid && (count >= size_sg_header))
req_pack_id = shp->pack_id;
srp = sg_get_request(sfp, req_pack_id);
if (! srp) { /* now wait on packet to arrive */
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
res = 0; /* following is a macro that beats race condition */
__wait_event_interruptible(sfp->read_wait,
(srp = sg_get_request(sfp, req_pack_id)),
res);
if (res)
return res; /* -ERESTARTSYS because signal hit process */
}
if (2 != sfp->underrun_flag)
srp->header.pack_len = srp->header.reply_len; /* Why ????? */
/* Now copy the result back to the user buffer. */
if (count >= size_sg_header) {
__copy_to_user(buf, &srp->header, size_sg_header);
buf += size_sg_header;
if (count > srp->header.reply_len)
count = srp->header.reply_len;
if (count > size_sg_header) /* release does copy_to_user */
sg_finish_rem_req(srp, buf, count - size_sg_header);
else
sg_finish_rem_req(srp, NULL, 0);
}
else {
count = (srp->header.result == 0) ? 0 : -EIO;
sg_finish_rem_req(srp, NULL, 0);
}
return count;
}
static ssize_t sg_write(struct file * filp, const char * buf,
size_t count, loff_t *ppos)
{
unsigned long flags;
int mxsize, cmd_size, k;
unsigned char cmnd[MAX_COMMAND_SIZE];
int input_size;
unsigned char opcode;
Scsi_Cmnd * SCpnt;
Sg_device * sdp;
Sg_fd * sfp;
Sg_request * srp;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_write: dev=%d, count=%d\n",
MINOR(sdp->i_rdev), (int)count));
if(! scsi_block_when_processing_errors(sdp->device) )
return -ENXIO;
if (ppos != &filp->f_pos)
; /* FIXME: Hmm. Seek to the right place, or fail? */
if ((k = verify_area(VERIFY_READ, buf, count)))
return k; /* protects following copy_from_user()s + get_user()s */
if (count < (size_sg_header + 6))
return -EIO; /* The minimum scsi command length is 6 bytes. */
srp = sg_add_request(sfp);
if (! srp) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full, domain error\n"));
return -EDOM;
}
__copy_from_user(&srp->header, buf, size_sg_header);
buf += size_sg_header;
srp->header.pack_len = count;
__get_user(opcode, buf);
if (sfp->next_cmd_len > 0) {
if (sfp->next_cmd_len > MAX_COMMAND_SIZE) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: command length too long\n"));
sfp->next_cmd_len = 0;
return -EDOM;
}
cmd_size = sfp->next_cmd_len;
sfp->next_cmd_len = 0; /* reset so only this write() effected */
}
else {
cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */
if ((opcode >= 0xc0) && srp->header.twelve_byte)
cmd_size = 12;
}
SCSI_LOG_TIMEOUT(4, printk("sg_write: scsi opcode=0x%02x, cmd_size=%d\n",
(int)opcode, cmd_size));
/* Determine buffer size. */
input_size = count - cmd_size;
mxsize = (input_size > srp->header.reply_len) ? input_size :
srp->header.reply_len;
mxsize -= size_sg_header;
input_size -= size_sg_header;
if (input_size < 0) {
sg_remove_request(sfp, srp);
return -EIO; /* User did not pass enough bytes for this command. */
}
if ((k = sg_start_req(srp, mxsize, buf + cmd_size, input_size))) {
SCSI_LOG_TIMEOUT(1, printk("sg_write: build err=%d\n", k));
sg_finish_rem_req(srp, NULL, 0);
return k; /* probably out of space --> ENOMEM */
}
/* SCSI_LOG_TIMEOUT(7, printk("sg_write: allocating device\n")); */
if (! (SCpnt = scsi_allocate_device(NULL, sdp->device,
!(filp->f_flags & O_NONBLOCK)))) {
sg_finish_rem_req(srp, NULL, 0);
return -EAGAIN; /* No available command blocks at the moment */
}
/* SCSI_LOG_TIMEOUT(7, printk("sg_write: device allocated\n")); */
srp->my_cmdp = SCpnt;
SCpnt->request.rq_dev = sdp->i_rdev;
SCpnt->request.rq_status = RQ_ACTIVE;
SCpnt->sense_buffer[0] = 0;
SCpnt->cmd_len = cmd_size;
__copy_from_user(cmnd, buf, cmd_size);
/* Set the LUN field in the command structure, overriding user input */
cmnd[1]= (cmnd[1] & 0x1f) | (sdp->device->lun << 5);
/* SCSI_LOG_TIMEOUT(7, printk("sg_write: do cmd\n")); */
spin_lock_irqsave(&io_request_lock, flags);
SCpnt->use_sg = srp->data.use_sg;
SCpnt->sglist_len = srp->data.sglist_len;
SCpnt->bufflen = srp->data.bufflen;
if (1 == sfp->underrun_flag)
SCpnt->underflow = srp->data.bufflen;
else
SCpnt->underflow = 0;
SCpnt->buffer = srp->data.buffer;
srp->data.use_sg = 0;
srp->data.sglist_len = 0;
srp->data.bufflen = 0;
srp->data.buffer = NULL;
/* Now send everything of to mid-level. The next time we hear about this
packet is when sg_command_done() is called (ie a callback). */
scsi_do_cmd(SCpnt, (void *)cmnd,
(void *)SCpnt->buffer, mxsize,
sg_command_done, sfp->timeout, SG_DEFAULT_RETRIES);
/* 'mxsize' overwrites SCpnt->bufflen, hence need for b_malloc_len */
spin_unlock_irqrestore(&io_request_lock, flags);
/* SCSI_LOG_TIMEOUT(6, printk("sg_write: sent scsi cmd to mid-level\n")); */
return count;
}
static int sg_ioctl(struct inode * inode, struct file * filp,
unsigned int cmd_in, unsigned long arg)
{
int result, val;
Sg_device * sdp;
Sg_fd * sfp;
Sg_request * srp;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: dev=%d, cmd=0x%x\n",
MINOR(sdp->i_rdev), (int)cmd_in));
if(! scsi_block_when_processing_errors(sdp->device) )
return -ENXIO;
switch(cmd_in)
{
case SG_SET_TIMEOUT:
return get_user(sfp->timeout, (int *)arg);
case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */
return sfp->timeout; /* strange ..., for backward compatibility */
case SG_SET_FORCE_LOW_DMA:
result = get_user(val, (int *)arg);
if (result) return result;
if (val) {
sfp->low_dma = 1;
if ((0 == sfp->low_dma) && (0 == sg_res_in_use(sfp))) {
val = (int)sfp->reserve.bufflen;
sg_remove_scat(&sfp->reserve);
sg_build_reserve(sfp, val);
}
}
else
sfp->low_dma = sdp->device->host->unchecked_isa_dma;
return 0;
case SG_GET_LOW_DMA:
return put_user((int)sfp->low_dma, (int *)arg);
case SG_GET_SCSI_ID:
result = verify_area(VERIFY_WRITE, (void *)arg, sizeof(Sg_scsi_id));
if (result) return result;
else {
Sg_scsi_id * sg_idp = (Sg_scsi_id *)arg;
__put_user((int)sdp->device->host->host_no, &sg_idp->host_no);
__put_user((int)sdp->device->channel, &sg_idp->channel);
__put_user((int)sdp->device->id, &sg_idp->scsi_id);
__put_user((int)sdp->device->lun, &sg_idp->lun);
__put_user((int)sdp->device->type, &sg_idp->scsi_type);
__put_user(0, &sg_idp->unused1);
__put_user(0, &sg_idp->unused2);
__put_user(0, &sg_idp->unused3);
return 0;
}
case SG_SET_FORCE_PACK_ID:
result = get_user(val, (int *)arg);
if (result) return result;
sfp->force_packid = val ? 1 : 0;
return 0;
case SG_GET_PACK_ID:
result = verify_area(VERIFY_WRITE, (void *) arg, sizeof(int));
if (result) return result;
srp = sfp->headrp;
while (srp) {
if (! srp->my_cmdp) {
__put_user(srp->header.pack_id, (int *)arg);
return 0;
}
srp = srp->nextrp;
}
__put_user(-1, (int *)arg);
return 0;
case SG_GET_NUM_WAITING:
srp = sfp->headrp;
val = 0;
while (srp) {
if (! srp->my_cmdp)
++val;
srp = srp->nextrp;
}
return put_user(val, (int *)arg);
case SG_GET_SG_TABLESIZE:
return put_user(sdp->sg_tablesize, (int *)arg);
case SG_SET_RESERVED_SIZE:
if (O_RDWR != (filp->f_flags & O_ACCMODE))
return -EACCES;
result = get_user(val, (int *)arg);
if (result) return result;
if (val != sfp->reserve.bufflen) {
if (sg_res_in_use(sfp))
return -EBUSY;
sg_remove_scat(&sfp->reserve);
sg_build_reserve(sfp, val);
}
return 0;
case SG_GET_RESERVED_SIZE:
val = (int)sfp->reserve.bufflen;
return put_user(val, (int *)arg);
case SG_GET_MERGE_FD:
return put_user((int)sdp->merge_fd, (int *)arg);
case SG_SET_MERGE_FD:
if (O_RDWR != (filp->f_flags & O_ACCMODE))
return -EACCES; /* require write access since effect wider
then just this fd */
result = get_user(val, (int *)arg);
if (result) return result;
val = val ? 1 : 0;
if ((val ^ (0 != sdp->merge_fd)) &&
sdp->headfp && sdp->headfp->nextfp)
return -EBUSY; /* too much work if multiple fds already */
sdp->merge_fd = val;
return 0;
case SG_SET_COMMAND_Q:
result = get_user(val, (int *)arg);
if (result) return result;
sfp->cmd_q = val ? 1 : 0;
return 0;
case SG_GET_COMMAND_Q:
return put_user((int)sfp->cmd_q, (int *)arg);
case SG_SET_UNDERRUN_FLAG:
result = get_user(val, (int *)arg);
if (result) return result;
sfp->underrun_flag = val;
return 0;
case SG_GET_UNDERRUN_FLAG:
return put_user((int)sfp->underrun_flag, (int *)arg);
case SG_NEXT_CMD_LEN:
result = get_user(val, (int *)arg);
if (result) return result;
sfp->next_cmd_len = (val > 0) ? val : 0;
return 0;
case SG_GET_VERSION_NUM:
return put_user(sg_version_num, (int *)arg);
case SG_EMULATED_HOST:
return put_user(sdp->device->host->hostt->emulated, (int *)arg);
case SCSI_IOCTL_SEND_COMMAND:
/* Allow SCSI_IOCTL_SEND_COMMAND without checking suser() since the
user already has read/write access to the generic device and so
can execute arbitrary SCSI commands. */
if (O_RDWR != (filp->f_flags & O_ACCMODE))
return -EACCES; /* very dangerous things can be done here */
return scsi_ioctl_send_command(sdp->device, (void *)arg);
case SG_SET_DEBUG:
result = get_user(val, (int *)arg);
if (result) return result;
sdp->sgdebug = (char)val;
if (9 == sdp->sgdebug)
sg_debug(sdp, sfp, 0);
else if (sdp->sgdebug > 9)
sg_debug_all(sfp);
return 0;
case SCSI_IOCTL_GET_IDLUN:
case SCSI_IOCTL_GET_BUS_NUMBER:
case SCSI_IOCTL_PROBE_HOST:
case SG_GET_TRANSFORM:
return scsi_ioctl(sdp->device, cmd_in, (void *)arg);
default:
if (O_RDWR != (filp->f_flags & O_ACCMODE))
return -EACCES; /* don't know so take safe approach */
return scsi_ioctl(sdp->device, cmd_in, (void *)arg);
}
}
static unsigned int sg_poll(struct file * filp, poll_table * wait)
{
unsigned int res = 0;
Sg_device * sdp;
Sg_fd * sfp;
Sg_request * srp;
int count = 0;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return POLLERR;
poll_wait(filp, &sfp->read_wait, wait);
srp = sfp->headrp;
while (srp) { /* if any read waiting, flag it */
if (! (res || srp->my_cmdp))
res = POLLIN | POLLRDNORM;
++count;
srp = srp->nextrp;
}
if (0 == sfp->cmd_q) {
if (0 == count)
res |= POLLOUT | POLLWRNORM;
}
else if (count < SG_MAX_QUEUE)
res |= POLLOUT | POLLWRNORM;
SCSI_LOG_TIMEOUT(3, printk("sg_poll: dev=%d, res=0x%x\n",
MINOR(sdp->i_rdev), (int)res));
return res;
}
static int sg_fasync(int fd, struct file * filp, int mode)
{
int retval;
Sg_device * sdp;
Sg_fd * sfp;
if ((! (sfp = (Sg_fd *)filp->private_data)) || (! (sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_fasync: dev=%d, mode=%d\n",
MINOR(sdp->i_rdev), mode));
retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
return (retval < 0) ? retval : 0;
}
/* This function is called by the interrupt handler when we
* actually have a command that is complete. */
static void sg_command_done(Scsi_Cmnd * SCpnt)
{
int dev = MINOR(SCpnt->request.rq_dev);
Sg_device * sdp;
Sg_fd * sfp;
Sg_request * srp = NULL;
int closed = 0;
if ((NULL == sg_dev_arr) || (dev < 0) || (dev >= sg_template.dev_max)) {
SCSI_LOG_TIMEOUT(1, printk("sg__done: bad args dev=%d\n", dev));
scsi_release_command(SCpnt);
SCpnt = NULL;
return;
}
sdp = &sg_dev_arr[dev];
if (NULL == sdp->device)
return; /* Get out of here quick ... */
sfp = sdp->headfp;
while (sfp) {
srp = sfp->headrp;
while (srp) {
if (SCpnt == srp->my_cmdp)
break;
srp = srp->nextrp;
}
if (srp)
break;
sfp = sfp->nextfp;
}
if (! srp) {
SCSI_LOG_TIMEOUT(1, printk("sg__done: req missing, dev=%d\n", dev));
scsi_release_command(SCpnt);
SCpnt = NULL;
return;
}
/* First transfer ownership of data buffers to sg_device object. */
srp->data.use_sg = SCpnt->use_sg;
srp->data.sglist_len = SCpnt->sglist_len;
srp->data.bufflen = SCpnt->bufflen;
srp->data.buffer = SCpnt->buffer;
if (2 == sfp->underrun_flag)
srp->header.pack_len = SCpnt->underflow;
sg_clr_scpnt(SCpnt);
srp->my_cmdp = NULL;
SCSI_LOG_TIMEOUT(4, printk("sg__done: dev=%d, scsi_stat=%d, res=0x%x\n",
dev, (int)status_byte(SCpnt->result), (int)SCpnt->result));
memcpy(srp->header.sense_buffer, SCpnt->sense_buffer,
sizeof(SCpnt->sense_buffer));
switch (host_byte(SCpnt->result))
{ /* This setup of 'result' is for backward compatibility and is best
ignored by the user who should use target, host + driver status */
case DID_OK:
case DID_PASSTHROUGH:
case DID_SOFT_ERROR:
srp->header.result = 0;
break;
case DID_NO_CONNECT:
case DID_BUS_BUSY:
case DID_TIME_OUT:
srp->header.result = EBUSY;
break;
case DID_BAD_TARGET:
case DID_ABORT:
case DID_PARITY:
case DID_RESET:
case DID_BAD_INTR:
srp->header.result = EIO;
break;
case DID_ERROR:
if (SCpnt->sense_buffer[0] == 0 &&
status_byte(SCpnt->result) == GOOD)
srp->header.result = 0;
else
srp->header.result = EIO;
break;
default:
SCSI_LOG_TIMEOUT(1, printk(
"sg: unexpected host_byte=%d, dev=%d in 'done'\n",
host_byte(SCpnt->result), dev));
srp->header.result = EIO;
break;
}
/* Following if statement is a patch supplied by Eric Youngdale */
if (driver_byte(SCpnt->result) != 0
&& (SCpnt->sense_buffer[0] & 0x7f) == 0x70
&& (SCpnt->sense_buffer[2] & 0xf) == UNIT_ATTENTION
&& sdp->device->removable) {
/* Detected disc change. Set the bit - this may be used if there are */
/* filesystems using this device. */
sdp->device->changed = 1;
}
srp->header.target_status = status_byte(SCpnt->result);
if ((sdp->sgdebug > 0) &&
((CHECK_CONDITION == srp->header.target_status) ||
(COMMAND_TERMINATED == srp->header.target_status)))
print_sense("sg_command_done", SCpnt);
srp->header.host_status = host_byte(SCpnt->result);
srp->header.driver_status = driver_byte(SCpnt->result);
scsi_release_command(SCpnt);
SCpnt = NULL;
if (sfp->closed) { /* whoops this fd already released, cleanup */
closed = 1;
SCSI_LOG_TIMEOUT(1,
printk("sg__done: already closed, freeing ...\n"));
/* should check if module is unloaded <<<<<<< */
sg_finish_rem_req(srp, NULL, 0);
if (NULL == sfp->headrp) {
SCSI_LOG_TIMEOUT(1,
printk("sg__done: already closed, final cleanup\n"));
sg_remove_sfp(sdp, sfp);
}
}
/* Now wake up any sg_read() that is waiting for this packet. */
wake_up_interruptible(&sfp->read_wait);
if ((sfp->async_qp) && (! closed))
kill_fasync(sfp->async_qp, SIGPOLL);
}
static void sg_debug_all(const Sg_fd * sfp)
{
const Sg_device * sdp = sg_dev_arr;
int k;
if (NULL == sg_dev_arr) {
printk("sg_debug_all: sg_dev_arr NULL, death is imminent\n");
return;
}
if (! sfp)
printk("sg_debug_all: sfp (file descriptor pointer) NULL\n");
printk("sg_debug_all: dev_max=%d, %s\n",
sg_template.dev_max, sg_version_str);
printk(" scsi_dma_free_sectors=%u, sg_pool_secs_aval=%d\n",
scsi_dma_free_sectors, sg_pool_secs_avail);
printk(" sg_big_buff=%d\n", sg_big_buff);
#ifdef SG_DEBUG
printk(" malloc counts, kmallocs=%d, dma_pool=%d, pages=%d\n",
sg_num_kmal, sg_num_pool, sg_num_page);
#endif
for (k = 0; k < sg_template.dev_max; ++k, ++sdp) {
if (sdp->headfp) {
if (! sfp)
sfp = sdp->headfp; /* just to keep things going */
else if (sdp == sfp->parentdp)
printk(" ***** Invoking device follows *****\n");
sg_debug(sdp, sfp, 1);
}
}
}
static void sg_debug(const Sg_device * sdp, const Sg_fd * sfp, int part_of)
{
Sg_fd * fp;
Sg_request * srp;
int dev;
int k;
if (! sfp)
printk("sg_debug: sfp (file descriptor pointer) NULL\n");
if (! sdp) {
printk("sg_debug: sdp pointer (to device) NULL\n");
return;
}
else if (! sdp->device) {
printk("sg_debug: device detached ??\n");
return;
}
dev = MINOR(sdp->i_rdev);
if (part_of)
printk(" >>> device=%d(sg%c), ", dev, 'a' + dev);
else
printk("sg_debug: device=%d(sg%c), ", dev, 'a' + dev);
printk("scsi%d chan=%d id=%d lun=%d em=%d\n", sdp->device->host->host_no,
sdp->device->channel, sdp->device->id, sdp->device->lun,
sdp->device->host->hostt->emulated);
printk(" sg_tablesize=%d, excl=%d, sgdebug=%d, merge_fd=%d\n",
sdp->sg_tablesize, sdp->exclude, sdp->sgdebug, sdp->merge_fd);
if (! part_of) {
printk(" scsi_dma_free_sectors=%u, sg_pool_secs_aval=%d\n",
scsi_dma_free_sectors, sg_pool_secs_avail);
#ifdef SG_DEBUG
printk(" mallocs: kmallocs=%d, dma_pool=%d, pages=%d\n",
sg_num_kmal, sg_num_pool, sg_num_page);
#endif
}
fp = sdp->headfp;
for (k = 1; fp; fp = fp->nextfp, ++k) {
if (sfp == fp)
printk(" *** Following data belongs to invoking FD ***\n");
else if (! fp->parentdp)
printk(">> Following FD has NULL parent pointer ???\n");
printk(" FD(%d): timeout=%d, bufflen=%d, use_sg=%d\n",
k, fp->timeout, fp->reserve.bufflen, (int)fp->reserve.use_sg);
printk(" low_dma=%d, cmd_q=%d, s_sc_len=%d, f_packid=%d\n",
(int)fp->low_dma, (int)fp->cmd_q, (int)fp->save_scat_len,
(int)fp->force_packid);
printk(" urun_flag=%d, next_cmd_len=%d, closed=%d\n",
(int)fp->underrun_flag, (int)fp->next_cmd_len,
(int)fp->closed);
srp = fp->headrp;
if (NULL == srp)
printk(" No requests active\n");
while (srp) {
if (srp->res_used)
printk("reserved buff >> ");
else
printk(" ");
if (srp->my_cmdp)
printk("written: pack_id=%d, bufflen=%d, use_sg=%d\n",
srp->header.pack_id, srp->my_cmdp->bufflen,
srp->my_cmdp->use_sg);
else
printk("to_read: pack_id=%d, bufflen=%d, use_sg=%d\n",
srp->header.pack_id, srp->data.bufflen, srp->data.use_sg);
if (! srp->parentfp)
printk(">> request has NULL parent pointer ???\n");
srp = srp->nextrp;
}
}
}
static struct file_operations sg_fops = {
NULL, /* lseek */
sg_read, /* read */
sg_write, /* write */
NULL, /* readdir */
sg_poll, /* poll */
sg_ioctl, /* ioctl */
NULL, /* mmap */
sg_open, /* open */
NULL, /* flush */
sg_release, /* release, was formerly sg_close */
NULL, /* fsync */
sg_fasync, /* fasync */
NULL, /* check_media_change */
NULL, /* revalidate */
NULL, /* lock */
};
static int sg_detect(Scsi_Device * scsidp)
{
switch (scsidp->type) {
case TYPE_DISK:
case TYPE_MOD:
case TYPE_ROM:
case TYPE_WORM:
case TYPE_TAPE: break;
default:
printk("Detected scsi generic sg%c at scsi%d,"
" channel %d, id %d, lun %d\n",
'a'+sg_template.dev_noticed,
scsidp->host->host_no, scsidp->channel,
scsidp->id, scsidp->lun);
}
sg_template.dev_noticed++;
return 1;
}
/* Driver initialization */
static int sg_init()
{
static int sg_registered = 0;
if (sg_template.dev_noticed == 0) return 0;
if(!sg_registered) {
if (register_chrdev(SCSI_GENERIC_MAJOR,"sg",&sg_fops))
{
printk("Unable to get major %d for generic SCSI device\n",
SCSI_GENERIC_MAJOR);
return 1;
}
sg_registered++;
}
/* If we have already been through here, return */
if(sg_dev_arr) return 0;
SCSI_LOG_TIMEOUT(3, printk("sg_init\n"));
sg_dev_arr = (Sg_device *)
scsi_init_malloc((sg_template.dev_noticed + SG_EXTRA_DEVS)
* sizeof(Sg_device), GFP_ATOMIC);
if (NULL == sg_dev_arr) {
printk("sg_init: no space for sg_dev_arr\n");
return 1;
}
sg_template.dev_max = sg_template.dev_noticed + SG_EXTRA_DEVS;
return 0;
}
static int sg_attach(Scsi_Device * scsidp)
{
Sg_device * sdp = sg_dev_arr;
int k;
if ((sg_template.nr_dev >= sg_template.dev_max) || (! sdp))
{
scsidp->attached--;
return 1;
}
for(k = 0; k < sg_template.dev_max; k++, sdp++)
if(! sdp->device) break;
if(k >= sg_template.dev_max) panic ("scsi_devices corrupt (sg)");
SCSI_LOG_TIMEOUT(3, printk("sg_attach: dev=%d \n", k));
sdp->device = scsidp;
init_waitqueue_head(&sdp->o_excl_wait);
sdp->headfp= NULL;
sdp->exclude = 0;
sdp->merge_fd = 0; /* Cope with SG_DEF_MERGE_FD on open */
sdp->sgdebug = 0;
sdp->sg_tablesize = scsidp->host ? scsidp->host->sg_tablesize : 0;
sdp->i_rdev = MKDEV(SCSI_GENERIC_MAJOR, k);
sg_template.nr_dev++;
return 0;
}
/* Called at 'finish' of init process, after all attaches */
static void sg_finish(void)
{
SCSI_LOG_TIMEOUT(3, printk("sg_finish: dma_free_sectors=%u\n",
scsi_dma_free_sectors));
}
static void sg_detach(Scsi_Device * scsidp)
{
Sg_device * sdp = sg_dev_arr;
unsigned long flags = 0;
Sg_fd * sfp;
Sg_request * srp;
int k;
if (NULL == sdp) return; /* all is not well ... */
for (k = 0; k < sg_template.dev_max; k++, sdp++) {
if(sdp->device != scsidp)
continue; /* dirty but lowers nesting */
if (sdp->headfp) {
/* Need to stop sg_command_done() playing with this list during this loop */
spin_lock_irqsave(&io_request_lock, flags);
sfp = sdp->headfp;
while (sfp) {
srp = sfp->headrp;
while (srp) {
if (srp->my_cmdp)
sg_shorten_timeout(srp->my_cmdp);
srp = srp->nextrp;
}
sfp = sfp->nextfp;
}
spin_unlock_irqrestore(&io_request_lock, flags);
SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty, sleep(3)\n", k));
scsi_sleep(3); /* sleep 3 jiffies, hoping for timeout to go off */
}
else {
SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
sdp->device = NULL;
}
scsidp->attached--;
sg_template.nr_dev--;
/* avoid associated device /dev/sg? being incremented
* each time module is inserted/removed , <dan@lectra.fr> */
sg_template.dev_noticed--;
return;
}
return;
}
#ifdef MODULE
int init_module(void) {
sg_template.module = &__this_module;
return scsi_register_module(MODULE_SCSI_DEV, &sg_template);
}
void cleanup_module( void)
{
scsi_unregister_module(MODULE_SCSI_DEV, &sg_template);
unregister_chrdev(SCSI_GENERIC_MAJOR, "sg");
if(sg_dev_arr != NULL) {
/* Really worrying situation of writes still pending and get here */
/* Strategy: shorten timeout on release + wait on detach ... */
scsi_init_free((char *) sg_dev_arr,
(sg_template.dev_noticed + SG_EXTRA_DEVS)
* sizeof(Sg_device));
sg_dev_arr = NULL;
}
sg_template.dev_max = 0;
}
#endif /* MODULE */
#if 0
extern void scsi_times_out (Scsi_Cmnd * SCpnt);
extern void scsi_old_times_out (Scsi_Cmnd * SCpnt);
#endif
/* Can't see clean way to abort a command so shorten timeout to 1 jiffy */
static void sg_shorten_timeout(Scsi_Cmnd * scpnt)
{
#if 0 /* scsi_syms.c is very miserly about exported functions */
scsi_delete_timer(scpnt);
if (! scpnt)
return;
scpnt->timeout_per_command = 1; /* try 1 jiffy (perhaps 0 jiffies) */
if (scpnt->host->hostt->use_new_eh_code)
scsi_add_timer(scpnt, scpnt->timeout_per_command, scsi_times_out);
else
scsi_add_timer(scpnt, scpnt->timeout_per_command,
scsi_old_times_out);
#else
scsi_sleep(HZ); /* just sleep 1 second and hope ... */
#endif
}
static int sg_start_req(Sg_request * srp, int max_buff_size,
const char * inp, int num_write_xfer)
{
int res;
Sg_fd * sfp = srp->parentfp;
Sg_scatter_hold * req_schp = &srp->data;
Sg_scatter_hold * rsv_schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_start_req: max_buff_size=%d\n",
max_buff_size));
if ((! sg_res_in_use(sfp)) && (max_buff_size <= rsv_schp->bufflen)) {
sg_link_reserve(sfp, srp, max_buff_size);
sg_write_xfer(req_schp, inp, num_write_xfer);
}
else {
res = sg_build_scat(req_schp, max_buff_size, sfp);
if (res) {
sg_remove_scat(req_schp);
return res;
}
sg_write_xfer(req_schp, inp, num_write_xfer);
}
return 0;
}
static void sg_finish_rem_req(Sg_request * srp, char * outp,
int num_read_xfer)
{
Sg_fd * sfp = srp->parentfp;
Sg_scatter_hold * req_schp = &srp->data;
SCSI_LOG_TIMEOUT(4, printk("sg_finish_rem_req: res_used=%d\n",
(int)srp->res_used));
if (num_read_xfer > 0)
sg_read_xfer(req_schp, outp, num_read_xfer);
if (srp->res_used)
sg_unlink_reserve(sfp, srp);
else
sg_remove_scat(req_schp);
sg_remove_request(sfp, srp);
}
static int sg_build_scat(Sg_scatter_hold * schp, int buff_size,
const Sg_fd * sfp)
{
int ret_sz, mem_src;
int blk_size = buff_size;
char * p = NULL;
if ((blk_size < 0) || (! sfp))
return -EFAULT;
if (0 == blk_size)
++blk_size; /* don't know why */
/* round request up to next highest SG_SECTOR_SZ byte boundary */
blk_size = (blk_size + SG_SECTOR_MSK) & (~SG_SECTOR_MSK);
SCSI_LOG_TIMEOUT(4, printk("sg_build_scat: buff_size=%d, blk_size=%d\n",
buff_size, blk_size));
if (blk_size <= SG_SCATTER_SZ) {
mem_src = SG_HEAP_PAGE;
p = sg_malloc(sfp, blk_size, &ret_sz, &mem_src);
if (! p)
return -ENOMEM;
if (blk_size == ret_sz) { /* got it on the first attempt */
schp->use_sg = 0;
schp->buffer = p;
schp->bufflen = blk_size;
schp->mem_src = mem_src;
schp->b_malloc_len = blk_size;
return 0;
}
}
else {
mem_src = SG_HEAP_PAGE;
p = sg_malloc(sfp, SG_SCATTER_SZ, &ret_sz, &mem_src);
if (! p)
return -ENOMEM;
}
/* Want some local declarations, so start new block ... */
{ /* lets try and build a scatter gather list */
struct scatterlist * sclp;
int k, rem_sz, num, nxt;
int sc_bufflen = PAGE_SIZE;
int mx_sc_elems = (sc_bufflen / sizeof(struct scatterlist)) - 1;
int sg_tablesize = sfp->parentdp->sg_tablesize;
int first = 1;
k = SG_HEAP_KMAL; /* want to protect mem_src, use k as scratch */
schp->buffer = (struct scatterlist *)sg_malloc(sfp,
sc_bufflen, &num, &k);
schp->mem_src = (char)k;
/* N.B. ret_sz and mem_src carried into this block ... */
if (! schp->buffer)
return -ENOMEM;
else if (num != sc_bufflen) {
sc_bufflen = num;
mx_sc_elems = (sc_bufflen / sizeof(struct scatterlist)) - 1;
}
schp->sglist_len = sc_bufflen;
memset(schp->buffer, 0, sc_bufflen);
for (k = 0, sclp = schp->buffer, rem_sz = blk_size, nxt =0;
(k < sg_tablesize) && (rem_sz > 0) && (k < mx_sc_elems);
++k, rem_sz -= ret_sz, ++sclp) {
if (first)
first = 0;
else {
num = (rem_sz > SG_SCATTER_SZ) ? SG_SCATTER_SZ : rem_sz;
mem_src = SG_HEAP_PAGE;
p = sg_malloc(sfp, num, &ret_sz, &mem_src);
if (! p)
break;
}
sclp->address = p;
sclp->length = ret_sz;
sclp->alt_address = (char *)(long)mem_src;
SCSI_LOG_TIMEOUT(5,
printk("sg_build_build: k=%d, a=0x%p, len=%d, ms=%d\n",
k, sclp->address, ret_sz, mem_src));
} /* end of for loop */
schp->use_sg = k;
SCSI_LOG_TIMEOUT(5,
printk("sg_build_scat: use_sg=%d, rem_sz=%d\n", k, rem_sz));
schp->bufflen = blk_size;
if (rem_sz > 0) /* must have failed */
return -ENOMEM;
}
return 0;
}
static void sg_write_xfer(Sg_scatter_hold * schp, const char * inp,
int num_write_xfer)
{
SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_write_xfer=%d, use_sg=%d\n",
num_write_xfer, schp->use_sg));
if ((! inp) || (num_write_xfer <= 0))
return;
if (schp->use_sg > 0) {
int k, num;
struct scatterlist * sclp = (struct scatterlist *)schp->buffer;
for (k = 0; (k < schp->use_sg) && sclp->address; ++k, ++sclp) {
num = (int)sclp->length;
if (num > num_write_xfer) {
__copy_from_user(sclp->address, inp, num_write_xfer);
break;
}
else {
__copy_from_user(sclp->address, inp, num);
num_write_xfer -= num;
if (num_write_xfer <= 0)
break;
inp += num;
}
}
}
else
__copy_from_user(schp->buffer, inp, num_write_xfer);
}
static void sg_remove_scat(Sg_scatter_hold * schp)
{
SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: use_sg=%d\n", schp->use_sg));
if(schp->use_sg > 0) {
int k, mem_src;
struct scatterlist * sclp = (struct scatterlist *)schp->buffer;
for (k = 0; (k < schp->use_sg) && sclp->address; ++k, ++sclp) {
mem_src = (int)(long)sclp->alt_address;
SCSI_LOG_TIMEOUT(5,
printk("sg_remove_scat: k=%d, a=0x%p, len=%d, ms=%d\n",
k, sclp->address, sclp->length, mem_src));
sg_free(sclp->address, sclp->length, mem_src);
sclp->address = NULL;
sclp->length = 0;
}
sg_free(schp->buffer, schp->sglist_len, schp->mem_src);
}
else if (schp->buffer)
sg_free(schp->buffer, schp->b_malloc_len, schp->mem_src);
schp->buffer = NULL;
schp->bufflen = 0;
schp->use_sg = 0;
schp->sglist_len = 0;
}
static void sg_read_xfer(Sg_scatter_hold * schp, char * outp,
int num_read_xfer)
{
SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_read_xfer=%d\n",
num_read_xfer));
if ((! outp) || (num_read_xfer <= 0))
return;
if(schp->use_sg > 0) {
int k, num;
struct scatterlist * sclp = (struct scatterlist *)schp->buffer;
for (k = 0; (k < schp->use_sg) && sclp->address; ++k, ++sclp) {
num = (int)sclp->length;
if (num > num_read_xfer) {
__copy_to_user(outp, sclp->address, num_read_xfer);
break;
}
else {
__copy_to_user(outp, sclp->address, num);
num_read_xfer -= num;
if (num_read_xfer <= 0)
break;
outp += num;
}
}
}
else
__copy_to_user(outp, schp->buffer, num_read_xfer);
}
static void sg_build_reserve(Sg_fd * sfp, int req_size)
{
Sg_scatter_hold * schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_build_reserve: req_size=%d\n", req_size));
do {
if (req_size < PAGE_SIZE)
req_size = PAGE_SIZE;
if (0 == sg_build_scat(schp, req_size, sfp))
return;
else
sg_remove_scat(schp);
req_size >>= 1; /* divide by 2 */
} while (req_size > (PAGE_SIZE / 2));
}
static void sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)
{
Sg_scatter_hold * req_schp = &srp->data;
Sg_scatter_hold * rsv_schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size));
if (rsv_schp->use_sg > 0) {
int k, num;
int rem = size;
struct scatterlist * sclp = (struct scatterlist *)rsv_schp->buffer;
for (k = 0; k < rsv_schp->use_sg; ++k, ++sclp) {
num = (int)sclp->length;
if (rem <= num) {
sfp->save_scat_len = num;
sclp->length = (unsigned)rem;
break;
}
else
rem -= num;
}
if (k < rsv_schp->use_sg) {
req_schp->use_sg = k + 1; /* adjust scatter list length */
req_schp->bufflen = size;
req_schp->sglist_len = rsv_schp->sglist_len;
req_schp->buffer = rsv_schp->buffer;
req_schp->mem_src = rsv_schp->mem_src;
req_schp->b_malloc_len = rsv_schp->b_malloc_len;
}
else
SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n"));
}
else {
req_schp->use_sg = 0;
req_schp->bufflen = size;
req_schp->buffer = rsv_schp->buffer;
req_schp->mem_src = rsv_schp->mem_src;
req_schp->use_sg = rsv_schp->use_sg;
req_schp->b_malloc_len = rsv_schp->b_malloc_len;
}
srp->res_used = 1;
}
static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)
{
Sg_scatter_hold * req_schp = &srp->data;
Sg_scatter_hold * rsv_schp = &sfp->reserve;
SCSI_LOG_TIMEOUT(4, printk("sg_unlink_reserve: req->use_sg=%d\n",
(int)req_schp->use_sg));
if (rsv_schp->use_sg > 0) {
struct scatterlist * sclp = (struct scatterlist *)rsv_schp->buffer;
if (sfp->save_scat_len > 0)
(sclp + (req_schp->use_sg - 1))->length =
(unsigned)sfp->save_scat_len;
else
SCSI_LOG_TIMEOUT(1, printk(
"sg_unlink_reserve: BAD save_scat_len\n"));
}
req_schp->use_sg = 0;
req_schp->bufflen = 0;
req_schp->buffer = NULL;
req_schp->sglist_len = 0;
sfp->save_scat_len = 0;
srp->res_used = 0;
}
static Sg_request * sg_get_request(const Sg_fd * sfp, int pack_id)
{
Sg_request * resp = NULL;
resp = sfp->headrp;
while (resp) {
if ((! resp->my_cmdp) &&
((-1 == pack_id) || (resp->header.pack_id == pack_id)))
return resp;
resp = resp->nextrp;
}
return resp;
}
/* always adds to end of list */
static Sg_request * sg_add_request(Sg_fd * sfp)
{
int k;
Sg_request * resp = NULL;
Sg_request * rp;
resp = sfp->headrp;
rp = sfp->req_arr;
if (! resp) {
resp = rp;
sfp->headrp = resp;
}
else {
if (0 == sfp->cmd_q)
resp = NULL; /* command queuing disallowed */
else {
for (k = 0, rp; k < SG_MAX_QUEUE; ++k, ++rp) {
if (! rp->parentfp)
break;
}
if (k < SG_MAX_QUEUE) {
while (resp->nextrp) resp = resp->nextrp;
resp->nextrp = rp;
resp = rp;
}
else
resp = NULL;
}
}
if (resp) {
resp->parentfp = sfp;
resp->nextrp = NULL;
resp->res_used = 0;
memset(&resp->data, 0, sizeof(Sg_scatter_hold));
memset(&resp->header, 0, sizeof(struct sg_header));
resp->my_cmdp = NULL;
}
return resp;
}
/* Return of 1 for found; 0 for not found */
static int sg_remove_request(Sg_fd * sfp, const Sg_request * srp)
{
Sg_request * prev_rp;
Sg_request * rp;
if ((! sfp) || (! srp) || (! sfp->headrp))
return 0;
prev_rp = sfp->headrp;
if (srp == prev_rp) {
prev_rp->parentfp = NULL;
sfp->headrp = prev_rp->nextrp;
return 1;
}
while ((rp = prev_rp->nextrp)) {
if (srp == rp) {
rp->parentfp = NULL;
prev_rp->nextrp = rp->nextrp;
return 1;
}
prev_rp = rp;
}
return 0;
}
static Sg_fd * sg_add_sfp(Sg_device * sdp, int dev, int get_reserved)
{
Sg_fd * sfp;
if (sdp->merge_fd) {
++sdp->merge_fd;
return sdp->headfp;
}
sfp = (Sg_fd *)sg_low_malloc(sizeof(Sg_fd), 0, SG_HEAP_KMAL, 0);
if (!sfp)
return NULL;
memset(sfp, 0, sizeof(Sg_fd));
sfp->my_mem_src = SG_HEAP_KMAL;
init_waitqueue_head(&sfp->read_wait);
sfp->timeout = SG_DEFAULT_TIMEOUT;
sfp->force_packid = SG_DEF_FORCE_PACK_ID;
sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
sdp->device->host->unchecked_isa_dma : 1;
sfp->cmd_q = SG_DEF_COMMAND_Q;
sfp->underrun_flag = SG_DEF_UNDERRUN_FLAG;
sfp->parentdp = sdp;
if (! sdp->headfp)
sdp->headfp = sfp;
else { /* add to tail of existing list */
Sg_fd * pfp = sdp->headfp;
while (pfp->nextfp)
pfp = pfp->nextfp;
pfp->nextfp = sfp;
}
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p, m_s=%d\n",
sfp, (int)sfp->my_mem_src));
if (get_reserved) {
sg_build_reserve(sfp, SG_DEF_RESERVED_SIZE);
sg_big_buff = sfp->reserve.bufflen; /* sysctl shows most recent size */
SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, use_sg=%d\n",
sfp->reserve.bufflen, sfp->reserve.use_sg));
}
return sfp;
}
static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
{
Sg_request * srp;
Sg_request * tsrp;
int dirty = 0;
int res = 0;
if (sdp->merge_fd) {
if (--sdp->merge_fd)
return 0; /* if merge_fd then dec merge_fd counter */
}
srp = sfp->headrp;
if (srp) {
/* Need to stop sg_command_done() playing with this list during this loop */
while (srp) {
tsrp = srp->nextrp;
if (! srp->my_cmdp)
sg_finish_rem_req(srp, NULL, 0);
else
++dirty;
srp = tsrp;
}
}
if (0 == dirty) {
Sg_fd * fp;
Sg_fd * prev_fp = sdp->headfp;
if (sfp == prev_fp)
sdp->headfp = prev_fp->nextfp;
else {
while ((fp = prev_fp->nextfp)) {
if (sfp == fp) {
prev_fp->nextfp = fp->nextfp;
break;
}
prev_fp = fp;
}
}
if (sfp->reserve.bufflen > 0) {
SCSI_LOG_TIMEOUT(6, printk("sg_remove_sfp: bufflen=%d, use_sg=%d\n",
(int)sfp->reserve.bufflen, (int)sfp->reserve.use_sg));
sg_remove_scat(&sfp->reserve);
}
sfp->parentdp = NULL;
SCSI_LOG_TIMEOUT(6, printk("sg_remove_sfp: sfp=0x%p\n", sfp));
sg_low_free((char *)sfp, sizeof(Sg_fd), sfp->my_mem_src);
res = 1;
}
else {
sfp->closed = 1; /* flag dirty state on this fd */
SCSI_LOG_TIMEOUT(1, printk(
"sg_remove_sfp: worrisome, %d writes pending\n", dirty));
}
return res;
}
static int sg_res_in_use(const Sg_fd * sfp)
{
const Sg_request * srp = sfp->headrp;
while (srp) {
if (srp->res_used)
return 1;
srp = srp->nextrp;
}
return 0;
}
/* If retSzp==NULL want exact size or fail */
/* sg_low_malloc() should always be called from a process context allowing
GFP_KERNEL to be used instead of GFP_ATOMIC */
static char * sg_low_malloc(int rqSz, int lowDma, int mem_src, int * retSzp)
{
char * resp = NULL;
int page_mask = lowDma ? (GFP_KERNEL | GFP_DMA) : GFP_KERNEL;
if (rqSz <= 0)
return resp;
if (SG_HEAP_KMAL == mem_src) {
page_mask = lowDma ? (GFP_ATOMIC | GFP_DMA) : GFP_ATOMIC;
/* Seen kmalloc(..,GFP_KERNEL) hang for 40 secs! */
resp = kmalloc(rqSz, page_mask);
if (resp && retSzp) *retSzp = rqSz;
#ifdef SG_DEBUG
if (resp) ++sg_num_kmal;
#endif
return resp;
}
if (SG_HEAP_POOL == mem_src) {
int num_sect = rqSz / SG_SECTOR_SZ;
if (0 != (rqSz & SG_SECTOR_MSK)) {
if (! retSzp)
return resp;
++num_sect;
rqSz = num_sect * SG_SECTOR_SZ;
}
while (num_sect > 0) {
if ((num_sect <= sg_pool_secs_avail) &&
(scsi_dma_free_sectors > (SG_LOW_POOL_THRESHHOLD + num_sect))) {
resp = scsi_malloc(rqSz);
if (resp) {
if (retSzp) *retSzp = rqSz;
sg_pool_secs_avail -= num_sect;
#ifdef SG_DEBUG
++sg_num_pool;
#endif
return resp;
}
}
if (! retSzp)
return resp;
num_sect /= 2; /* try half as many */
rqSz = num_sect * SG_SECTOR_SZ;
}
}
else if (SG_HEAP_PAGE == mem_src) {
int order, a_size;
int resSz = rqSz;
for (order = 0, a_size = PAGE_SIZE;
a_size < rqSz; order++, a_size <<= 1)
;
resp = (char *)__get_free_pages(page_mask, order);
while ((! resp) && order && retSzp) {
--order;
a_size >>= 1; /* divide by 2, until PAGE_SIZE */
resp = (char *)__get_free_pages(page_mask, order); /* try half */
resSz = a_size;
}
if (retSzp) *retSzp = resSz;
#ifdef SG_DEBUG
if (resp) ++sg_num_page;
#endif
}
else
printk("sg_low_malloc: bad mem_src=%d, rqSz=%df\n", mem_src, rqSz);
return resp;
}
static char * sg_malloc(const Sg_fd * sfp, int size, int * retSzp,
int * mem_srcp)
{
char * resp = NULL;
if (retSzp) *retSzp = size;
if (size <= 0)
;
else {
int low_dma = sfp->low_dma;
int l_ms = -1; /* invalid value */
switch (*mem_srcp)
{
case SG_HEAP_PAGE:
l_ms = (size < PAGE_SIZE) ? SG_HEAP_POOL : SG_HEAP_PAGE;
resp = sg_low_malloc(size, low_dma, l_ms, 0);
if (resp)
break;
resp = sg_low_malloc(size, low_dma, l_ms, &size);
if (! resp) {
l_ms = (SG_HEAP_POOL == l_ms) ? SG_HEAP_PAGE : SG_HEAP_POOL;
resp = sg_low_malloc(size, low_dma, l_ms, &size);
if (! resp) {
l_ms = SG_HEAP_KMAL;
resp = sg_low_malloc(size, low_dma, l_ms, &size);
}
}
if (resp && retSzp) *retSzp = size;
break;
case SG_HEAP_KMAL:
l_ms = SG_HEAP_PAGE;
resp = sg_low_malloc(size, low_dma, l_ms, 0);
if (resp)
break;
l_ms = SG_HEAP_POOL;
resp = sg_low_malloc(size, low_dma, l_ms, &size);
if (resp && retSzp) *retSzp = size;
break;
default:
SCSI_LOG_TIMEOUT(1, printk("sg_malloc: bad ms=%d\n", *mem_srcp));
break;
}
if (resp) *mem_srcp = l_ms;
}
SCSI_LOG_TIMEOUT(6, printk("sg_malloc: size=%d, ms=%d, ret=0x%p\n",
size, *mem_srcp, resp));
return resp;
}
static void sg_low_free(char * buff, int size, int mem_src)
{
if (! buff)
return;
if (SG_HEAP_POOL == mem_src) {
int num_sect = size / SG_SECTOR_SZ;
scsi_free(buff, size);
sg_pool_secs_avail += num_sect;
}
else if (SG_HEAP_KMAL == mem_src)
kfree(buff); /* size not used */
else if (SG_HEAP_PAGE == mem_src) {
int order, a_size;
for (order = 0, a_size = PAGE_SIZE;
a_size < size; order++, a_size <<= 1)
;
free_pages((unsigned long)buff, order);
}
else
printk("sg_low_free: bad mem_src=%d, buff=0x%p, rqSz=%df\n",
mem_src, buff, size);
}
static void sg_free(char * buff, int size, int mem_src)
{
SCSI_LOG_TIMEOUT(6,
printk("sg_free: buff=0x%p, size=%d\n", buff, size));
if ((! buff) || (size <= 0))
;
else
sg_low_free(buff, size, mem_src);
}
static void sg_clr_scpnt(Scsi_Cmnd * SCpnt)
{
SCpnt->use_sg = 0;
SCpnt->sglist_len = 0;
SCpnt->bufflen = 0;
SCpnt->buffer = NULL;
SCpnt->underflow = 0;
SCpnt->request.rq_dev = MKDEV(0, 0); /* "sg" _disowns_ command blk */
}
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