Below is an experimental patch, which adds a similar interface for the
character devices as we have for block devices.
(Patch bases on the earlier char device patches, complete patch is at
http://www.xs4all.nl/~zippel/cdev.diff)
I used the sg driver to demonstrate how it makes char device management a
lot simpler, I mostly just had to remove code and as a bonus I fixed a few
races. The first 256 devices appear under the normal major number, the
rest is allocated dynamically and is already exported via sysfs.
There still is a bit to do, but I hope it helps to understand that there
is more to do than just a larger dev_t.
bye, Roman
diff -ur linux-2.5.67-cdev4/drivers/scsi/sg.c linux-2.5.67-cdev5/drivers/scsi/sg.c
--- linux-2.5.67-cdev4/drivers/scsi/sg.c 2003-03-19 02:16:32.000000000 +0100
+++ linux-2.5.67-cdev5/drivers/scsi/sg.c 2003-04-14 20:41:31.000000000 +0200
@@ -107,13 +107,14 @@
#define SG_SECTOR_SZ 512
#define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
-#define SG_DEV_ARR_LUMP 6 /* amount to over allocate sg_dev_arr by */
-
static int sg_attach(Scsi_Device *);
static void sg_detach(Scsi_Device *);
static Scsi_Request *dummy_cmdp; /* only used for sizeof */
+#define SG_MINORS 256
+static unsigned long sg_index_bits[SG_MINORS / BITS_PER_LONG];
+static LIST_HEAD(sg_devlist);
static rwlock_t sg_dev_arr_lock = RW_LOCK_UNLOCKED; /* Also used to lock
file descriptor list for device */
@@ -177,6 +178,7 @@
} Sg_fd;
typedef struct sg_device { /* holds the state of each scsi generic device */
+ struct list_head list;
struct Scsi_Device_Template *driver;
Scsi_Device *device;
wait_queue_head_t o_excl_wait; /* queue open() when O_EXCL in use */
@@ -187,7 +189,7 @@
volatile char exclude; /* opened for exclusive access */
char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */
struct device sg_driverfs_dev;
- struct gendisk *disk;
+ struct char_device *cdev;
} Sg_device;
static int sg_fasync(int fd, struct file *filp, int mode);
@@ -214,7 +216,7 @@
static void sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp);
static char *sg_page_malloc(int rqSz, int lowDma, int *retSzp);
static void sg_page_free(char *buff, int size);
-static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev);
+static Sg_fd *sg_add_sfp(struct char_device *cdev);
static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp);
static Sg_request *sg_get_rq_mark(Sg_fd * sfp, int pack_id);
@@ -226,14 +228,8 @@
static int sg_allow_access(unsigned char opcode, char dev_type);
static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len);
// static void sg_unmap_and(Sg_scatter_hold * schp, int free_also);
-static Sg_device *sg_get_dev(int dev);
static inline unsigned char *sg_scatg2virt(const struct scatterlist *sclp);
-#ifdef CONFIG_PROC_FS
-static int sg_last_dev(void);
-#endif
-static Sg_device **sg_dev_arr = NULL;
-static int sg_dev_max;
static int sg_nr_dev;
#define SZ_SG_HEADER sizeof(struct sg_header)
@@ -244,25 +240,23 @@
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;
int retval = -EBUSY;
- SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
- sdp = sg_get_dev(dev);
- if ((!sdp) || (!sdp->device))
- return -ENXIO;
- if (sdp->detached)
- return -ENODEV;
+ SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%lx, flags=0x%x\n", inode->i_cdev->cd_dev, flags));
+ sfp = sg_add_sfp(inode->i_cdev);
+ if (IS_ERR(sfp))
+ return PTR_ERR(sfp);
+ sdp = inode->i_cdev->cd_data;
/* This driver's module count bumped by fops_get in <linux/fs.h> */
/* Prevent the device driver from vanishing while we sleep */
retval = scsi_device_get(sdp->device);
if (retval)
- return retval;
+ goto error_free;
if (!((flags & O_NONBLOCK) ||
scsi_block_when_processing_errors(sdp->device))) {
@@ -296,26 +290,13 @@
goto error_out;
}
}
- if (sdp->detached) {
- retval = -ENODEV;
- goto error_out;
- }
- if (!sdp->headfp) { /* no existing opens on this device */
- sdp->sgdebug = 0;
- sdp->sg_tablesize = sdp->device->host->sg_tablesize;
- }
- if ((sfp = sg_add_sfp(sdp, dev)))
- filp->private_data = sfp;
- else {
- if (flags & O_EXCL)
- sdp->exclude = 0; /* undo if error */
- retval = -ENOMEM;
- goto error_out;
- }
+ filp->private_data = sfp;
return 0;
error_out:
scsi_device_put(sdp->device);
+ error_free:
+ sg_remove_sfp(sdp, sfp);
return retval;
}
@@ -328,7 +309,7 @@
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
- SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->disk->disk_name));
+ SCSI_LOG_TIMEOUT(3, printk("sg_release: %s\n", sdp->cdev->cd_name));
sg_fasync(-1, filp, 0); /* remove filp from async notification list */
if (0 == sg_remove_sfp(sdp, sfp)) { /* Returns 1 when sdp gone */
if (!sdp->detached) {
@@ -355,7 +336,7 @@
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_read: %s, count=%d\n",
- sdp->disk->disk_name, (int) count));
+ sdp->cdev->cd_name, (int) count));
if (ppos != &filp->f_pos) ; /* FIXME: Hmm. Seek to the right place, or fail? */
if ((k = verify_area(VERIFY_WRITE, buf, count)))
return k;
@@ -508,7 +489,7 @@
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_write: %s, count=%d\n",
- sdp->disk->disk_name, (int) count));
+ sdp->cdev->cd_name, (int) count));
if (sdp->detached)
return -ENODEV;
if (!((filp->f_flags & O_NONBLOCK) ||
@@ -695,7 +676,6 @@
srp->my_cmdp = SRpnt;
q = SRpnt->sr_device->request_queue;
- SRpnt->sr_request->rq_disk = sdp->disk;
SRpnt->sr_sense_buffer[0] = 0;
SRpnt->sr_cmd_len = hp->cmd_len;
SRpnt->sr_use_sg = srp->data.k_use_sg;
@@ -747,7 +727,7 @@
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_ioctl: %s, cmd=0x%x\n",
- sdp->disk->disk_name, (int) cmd_in));
+ sdp->cdev->cd_name, (int) cmd_in));
read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));
switch (cmd_in) {
@@ -1050,7 +1030,7 @@
} else if (count < SG_MAX_QUEUE)
res |= POLLOUT | POLLWRNORM;
SCSI_LOG_TIMEOUT(3, printk("sg_poll: %s, res=0x%x\n",
- sdp->disk->disk_name, (int) res));
+ sdp->cdev->cd_name, (int) res));
return res;
}
@@ -1064,7 +1044,7 @@
if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))
return -ENXIO;
SCSI_LOG_TIMEOUT(3, printk("sg_fasync: %s, mode=%d\n",
- sdp->disk->disk_name, mode));
+ sdp->cdev->cd_name, mode));
retval = fasync_helper(fd, filp, mode, &sfp->async_qp);
return (retval < 0) ? retval : 0;
@@ -1256,7 +1236,7 @@
srp->done = 1;
SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n",
- sdp->disk->disk_name, srp->header.pack_id, (int) SRpnt->sr_result));
+ sdp->cdev->cd_name, srp->header.pack_id, (int) SRpnt->sr_result));
srp->header.resid = SCpnt->resid;
/* N.B. unit of duration changes here from jiffies to millisecs */
srp->header.duration =
@@ -1331,8 +1311,7 @@
sg_device_kdev_read(struct device *driverfs_dev, char *page)
{
Sg_device *sdp = list_entry(driverfs_dev, Sg_device, sg_driverfs_dev);
- return sprintf(page, "%x\n", MKDEV(sdp->disk->major,
- sdp->disk->first_minor));
+ return sprintf(page, "%lx\n", (long)sdp->cdev->cd_dev);
}
static DEVICE_ATTR(kdev,S_IRUGO,sg_device_kdev_read,NULL);
@@ -1347,70 +1326,30 @@
static int
sg_attach(Scsi_Device * scsidp)
{
- struct gendisk *disk;
+ struct char_device *cdev;
Sg_device *sdp = NULL;
+ dev_t dev;
unsigned long iflags;
int k, error;
- disk = alloc_disk(1);
- if (!disk)
- return -ENOMEM;
+ write_lock_irqsave(&sg_dev_arr_lock, iflags);
+ k = find_first_zero_bit(sg_index_bits, SG_MINORS);
+ if (k < SG_MINORS) {
+ __set_bit(k, sg_index_bits);
+ dev = MKDEV(SCSI_GENERIC_MAJOR, k);
+ } else
+ dev = 0;
+ write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+ cdev = alloc_chrdev(dev);
+ if (!cdev)
+ return -EBUSY;
error = scsi_slave_attach(scsidp);
if (error)
goto out_put;
-
- write_lock_irqsave(&sg_dev_arr_lock, iflags);
- if (sg_nr_dev >= sg_dev_max) { /* try to resize */
- Sg_device **tmp_da;
- int tmp_dev_max = sg_nr_dev + SG_DEV_ARR_LUMP;
-
- write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
- tmp_da = (Sg_device **)vmalloc(
- tmp_dev_max * sizeof(Sg_device *));
- if (NULL == tmp_da) {
- printk(KERN_ERR
- "sg_attach: device array cannot be resized\n");
- error = -ENOMEM;
- goto out_detach;
- }
- write_lock_irqsave(&sg_dev_arr_lock, iflags);
- memset(tmp_da, 0, tmp_dev_max * sizeof (Sg_device *));
- memcpy(tmp_da, sg_dev_arr,
- sg_dev_max * sizeof (Sg_device *));
- vfree((char *) sg_dev_arr);
- sg_dev_arr = tmp_da;
- sg_dev_max = tmp_dev_max;
- }
-find_empty_slot:
- for (k = 0; k < sg_dev_max; k++)
- if (!sg_dev_arr[k])
- break;
- if (k > SG_MAX_DEVS_MASK) {
- write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
- printk(KERN_WARNING
- "Unable to attach sg device <%d, %d, %d, %d>"
- " type=%d, minor number exceed %d\n",
- scsidp->host->host_no, scsidp->channel, scsidp->id,
- scsidp->lun, scsidp->type, SG_MAX_DEVS_MASK);
- if (NULL != sdp)
- vfree((char *) sdp);
- error = -ENODEV;
- goto out_detach;
- }
- if (k < sg_dev_max) {
- if (NULL == sdp) {
- write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
- sdp = (Sg_device *)vmalloc(sizeof(Sg_device));
- write_lock_irqsave(&sg_dev_arr_lock, iflags);
- if (!sg_dev_arr[k])
- goto find_empty_slot;
- }
- } else
- sdp = NULL;
+ sdp = kmalloc(sizeof(Sg_device), GFP_KERNEL);
if (NULL == sdp) {
- write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
printk(KERN_ERR "sg_attach: Sg_device cannot be allocated\n");
error = -ENOMEM;
goto out_detach;
@@ -1419,11 +1358,8 @@
SCSI_LOG_TIMEOUT(3, printk("sg_attach: dev=%d \n", k));
memset(sdp, 0, sizeof(*sdp));
sdp->driver = &sg_template;
- disk->private_data = &sdp->driver;
- sprintf(disk->disk_name, "sg%d", k);
- disk->major = SCSI_GENERIC_MAJOR;
- disk->first_minor = k;
- sdp->disk = disk;
+ cdev->cd_data = sdp;
+ sdp->cdev = cdev;
sdp->device = scsidp;
init_waitqueue_head(&sdp->o_excl_wait);
sdp->headfp = NULL;
@@ -1440,15 +1376,19 @@
sdp->sg_driverfs_dev.parent = &scsidp->sdev_driverfs_dev;
sdp->sg_driverfs_dev.bus = scsidp->sdev_driverfs_dev.bus;
+ error = add_chrdev(cdev, &sg_fops);
+ if (error)
+ goto out_free_sdp;
+ write_lock_irqsave(&sg_dev_arr_lock, iflags);
+ list_add(&sdp->list, &sg_devlist);
sg_nr_dev++;
- sg_dev_arr[k] = sdp;
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
device_register(&sdp->sg_driverfs_dev);
device_create_file(&sdp->sg_driverfs_dev, &dev_attr_type);
device_create_file(&sdp->sg_driverfs_dev, &dev_attr_kdev);
sdp->de = devfs_register(scsidp->de, "generic", DEVFS_FL_DEFAULT,
- SCSI_GENERIC_MAJOR, k,
+ MAJOR(cdev->cd_dev), MINOR(cdev->cd_dev),
S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP,
&sg_fops, sdp);
switch (scsidp->type) {
@@ -1467,10 +1407,12 @@
}
return 0;
+out_free_sdp:
+ kfree(sdp);
out_detach:
scsi_slave_detach(scsidp);
out_put:
- put_disk(disk);
+ del_chrdev(cdev);
return error;
}
@@ -1483,16 +1425,13 @@
Sg_fd *tsfp;
Sg_request *srp;
Sg_request *tsrp;
- int k, delay;
+ int delay;
- if (NULL == sg_dev_arr)
- return;
delay = 0;
write_lock_irqsave(&sg_dev_arr_lock, iflags);
- for (k = 0; k < sg_dev_max; k++) {
- sdp = sg_dev_arr[k];
- if ((NULL == sdp) || (sdp->device != scsidp))
- continue; /* dirty but lowers nesting */
+ list_for_each_entry(sdp, &sg_devlist, list) {
+ if (sdp->device != scsidp)
+ continue;
if (sdp->headfp) {
sdp->detached = 1;
for (sfp = sdp->headfp; sfp; sfp = tsfp) {
@@ -1512,13 +1451,12 @@
POLL_HUP);
}
}
- SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d, dirty\n", k));
- if (NULL == sdp->headfp) {
- sg_dev_arr[k] = NULL;
- }
+ SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%s, dirty\n", sdp->cdev->cd_name));
+ if (NULL == sdp->headfp)
+ list_del(&sdp->list);
} else { /* nothing active, simple case */
- SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%d\n", k));
- sg_dev_arr[k] = NULL;
+ SCSI_LOG_TIMEOUT(3, printk("sg_detach: dev=%s\n", sdp->cdev->cd_name));
+ list_del(&sdp->list);
}
scsi_slave_detach(scsidp);
sg_nr_dev--;
@@ -1532,10 +1470,12 @@
device_remove_file(&sdp->sg_driverfs_dev, &dev_attr_type);
device_remove_file(&sdp->sg_driverfs_dev, &dev_attr_kdev);
device_unregister(&sdp->sg_driverfs_dev);
- put_disk(sdp->disk);
- sdp->disk = NULL;
+ if (MAJOR(sdp->cdev->cd_dev) == SCSI_GENERIC_MAJOR)
+ clear_bit(MINOR(sdp->cdev->cd_dev), sg_index_bits);
+ del_chrdev(sdp->cdev);
+ sdp->cdev = NULL;
if (NULL == sdp->headfp)
- vfree((char *) sdp);
+ kfree(sdp);
}
if (delay)
@@ -1643,11 +1583,6 @@
#endif /* CONFIG_PROC_FS */
scsi_unregister_device(&sg_template);
unregister_chrdev(SCSI_GENERIC_MAJOR, "sg");
- if (sg_dev_arr != NULL) {
- vfree((char *) sg_dev_arr);
- sg_dev_arr = NULL;
- }
- sg_dev_max = 0;
}
static int
@@ -2447,14 +2382,15 @@
#endif
static Sg_fd *
-sg_add_sfp(Sg_device * sdp, int dev)
+sg_add_sfp(struct char_device *cdev)
{
+ Sg_device *sdp;
Sg_fd *sfp;
unsigned long iflags;
sfp = (Sg_fd *) sg_page_malloc(sizeof (Sg_fd), 0, 0);
if (!sfp)
- return NULL;
+ return ERR_PTR(-ENOMEM);
memset(sfp, 0, sizeof (Sg_fd));
init_waitqueue_head(&sfp->read_wait);
sfp->rq_list_lock = RW_LOCK_UNLOCKED;
@@ -2462,15 +2398,25 @@
sfp->timeout = SG_DEFAULT_TIMEOUT;
sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;
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->keep_orphan = SG_DEF_KEEP_ORPHAN;
- sfp->parentdp = sdp;
+
write_lock_irqsave(&sg_dev_arr_lock, iflags);
- if (!sdp->headfp)
+ sdp = cdev->cd_data;
+ if (!sdp || !sdp->device || sdp->detached) {
+ write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+ sg_page_free((char *) sfp, sizeof (Sg_fd));
+ return ERR_PTR(-ENODEV);
+ }
+ sfp->parentdp = sdp;
+ sfp->low_dma = (SG_DEF_FORCE_LOW_DMA == 0) ?
+ sdp->device->host->unchecked_isa_dma : 1;
+
+ if (!sdp->headfp) { /* no existing opens on this device */
sdp->headfp = sfp;
- else { /* add to tail of existing list */
+ sdp->sgdebug = 0;
+ sdp->sg_tablesize = sdp->device->host->sg_tablesize;
+ } else { /* add to tail of existing list */
Sg_fd *pfp = sdp->headfp;
while (pfp->nextfp)
pfp = pfp->nextfp;
@@ -2537,16 +2483,8 @@
write_lock_irqsave(&sg_dev_arr_lock, iflags);
__sg_remove_sfp(sdp, sfp);
if (sdp->detached && (NULL == sdp->headfp)) {
- int k, maxd;
-
- maxd = sg_dev_max;
- for (k = 0; k < maxd; ++k) {
- if (sdp == sg_dev_arr[k])
- break;
- }
- if (k < maxd)
- sg_dev_arr[k] = NULL;
- vfree((char *) sdp);
+ list_del(&sdp->list);
+ kfree(sdp);
res = 1;
}
write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
@@ -2662,37 +2600,6 @@
}
#ifdef CONFIG_PROC_FS
-static int
-sg_last_dev()
-{
- int k;
- unsigned long iflags;
-
- read_lock_irqsave(&sg_dev_arr_lock, iflags);
- for (k = sg_dev_max - 1; k >= 0; --k)
- if (sg_dev_arr[k] && sg_dev_arr[k]->device)
- break;
- read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
- return k + 1; /* origin 1 */
-}
-#endif
-
-static Sg_device *
-sg_get_dev(int dev)
-{
- Sg_device *sdp = NULL;
- unsigned long iflags;
-
- if (sg_dev_arr && (dev >= 0)) {
- read_lock_irqsave(&sg_dev_arr_lock, iflags);
- if (dev < sg_dev_max)
- sdp = sg_dev_arr[dev];
- read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
- }
- return sdp;
-}
-
-#ifdef CONFIG_PROC_FS
static struct proc_dir_entry *sg_proc_sgp = NULL;
@@ -2951,45 +2858,38 @@
off_t offset, int size)
{
Sg_device *sdp;
- int j, max_dev;
+ unsigned long iflags;
- if (NULL == sg_dev_arr) {
- PRINT_PROC("sg_dev_arr NULL, driver not initialized\n");
- return 1;
- }
- max_dev = sg_last_dev();
- PRINT_PROC("dev_max(currently)=%d max_active_device=%d (origin 1)\n",
- sg_dev_max, max_dev);
PRINT_PROC(" def_reserved_size=%d\n", sg_big_buff);
- for (j = 0; j < max_dev; ++j) {
- if ((sdp = sg_get_dev(j))) {
- struct scsi_device *scsidp = sdp->device;
-
- if (NULL == scsidp) {
- PRINT_PROC("device %d detached ??\n", j);
- continue;
- }
+ read_lock_irqsave(&sg_dev_arr_lock, iflags);
+ list_for_each_entry(sdp, &sg_devlist, list) {
+ struct scsi_device *scsidp = sdp->device;
- if (sg_get_nth_sfp(sdp, 0)) {
- PRINT_PROC(" >>> device=%s ",
- sdp->disk->disk_name);
- if (sdp->detached)
- PRINT_PROC("detached pending close ");
- else
- PRINT_PROC
- ("scsi%d chan=%d id=%d lun=%d em=%d",
- scsidp->host->host_no,
- scsidp->channel, scsidp->id,
- scsidp->lun,
- scsidp->host->hostt->emulated);
- PRINT_PROC(" sg_tablesize=%d excl=%d\n",
- sdp->sg_tablesize, sdp->exclude);
- }
- if (0 == sg_proc_debug_helper(buffer, len, begin,
- offset, size, sdp))
- return 0;
+ if (NULL == scsidp) {
+ PRINT_PROC("device %s detached ??\n", sdp->cdev->cd_name);
+ continue;
}
+
+ if (sg_get_nth_sfp(sdp, 0)) {
+ PRINT_PROC(" >>> device=%s ",
+ sdp->cdev->cd_name);
+ if (sdp->detached)
+ PRINT_PROC("detached pending close ");
+ else
+ PRINT_PROC
+ ("scsi%d chan=%d id=%d lun=%d em=%d",
+ scsidp->host->host_no,
+ scsidp->channel, scsidp->id,
+ scsidp->lun,
+ scsidp->host->hostt->emulated);
+ PRINT_PROC(" sg_tablesize=%d excl=%d\n",
+ sdp->sg_tablesize, sdp->exclude);
+ }
+ if (0 == sg_proc_debug_helper(buffer, len, begin,
+ offset, size, sdp))
+ return 0;
}
+ read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
return 1;
}
@@ -3004,13 +2904,12 @@
sg_proc_dev_info(char *buffer, int *len, off_t * begin, off_t offset, int size)
{
Sg_device *sdp;
- int j, max_dev;
struct scsi_device *scsidp;
+ unsigned long iflags;
- max_dev = sg_last_dev();
- for (j = 0; j < max_dev; ++j) {
- sdp = sg_get_dev(j);
- if (sdp && (scsidp = sdp->device) && (!sdp->detached))
+ read_lock_irqsave(&sg_dev_arr_lock, iflags);
+ list_for_each_entry(sdp, &sg_devlist, list) {
+ if ((scsidp = sdp->device) && !sdp->detached)
PRINT_PROC("%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n",
scsidp->host->host_no, scsidp->channel,
scsidp->id, scsidp->lun, (int) scsidp->type,
@@ -3021,6 +2920,7 @@
else
PRINT_PROC("-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");
}
+ read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
return 1;
}
@@ -3051,18 +2951,18 @@
off_t offset, int size)
{
Sg_device *sdp;
- int j, max_dev;
struct scsi_device *scsidp;
+ unsigned long iflags;
- max_dev = sg_last_dev();
- for (j = 0; j < max_dev; ++j) {
- sdp = sg_get_dev(j);
- if (sdp && (scsidp = sdp->device) && (!sdp->detached))
+ read_lock_irqsave(&sg_dev_arr_lock, iflags);
+ list_for_each_entry(sdp, &sg_devlist, list) {
+ if ((scsidp = sdp->device) && !sdp->detached)
PRINT_PROC("%8.8s\t%16.16s\t%4.4s\n",
scsidp->vendor, scsidp->model, scsidp->rev);
else
PRINT_PROC("<no active device>\n");
}
+ read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
return 1;
}
diff -ur linux-2.5.67-cdev4/fs/char_dev.c linux-2.5.67-cdev5/fs/char_dev.c
--- linux-2.5.67-cdev4/fs/char_dev.c 2003-04-14 13:11:24.000000000 +0200
+++ linux-2.5.67-cdev5/fs/char_dev.c 2003-04-14 20:41:31.000000000 +0200
@@ -125,6 +125,61 @@
}
}
+#define CHRDEV_NR 32768
+
+static unsigned long char_index_bits[CHRDEV_NR / BITS_PER_LONG];
+static spinlock_t char_index_lock = SPIN_LOCK_UNLOCKED;
+
+struct char_device *alloc_chrdev(dev_t dev)
+{
+ if (!dev) {
+ int index;
+
+ spin_lock(&char_index_lock);
+ index = find_first_zero_bit(char_index_bits, CHRDEV_NR);
+ if (index == CHRDEV_NR) {
+ spin_unlock(&char_index_lock);
+ return NULL;
+ }
+ __set_bit(index, char_index_bits);
+ spin_unlock(&char_index_lock);
+ dev = 0x10000 + index;
+ }
+ return cdget(dev);
+}
+
+int add_chrdev(struct char_device *cdev, struct file_operations *fops)
+{
+ int res = 0;
+
+ down(&cdev->cd_sem);
+ if (!cdev->cd_fops)
+ cdev->cd_fops = fops;
+ else
+ res = -EBUSY;
+ up(&cdev->cd_sem);
+
+ return res;
+}
+
+void unlink_chrdev(struct char_device *cdev)
+{
+ cdev->cd_fops = NULL;
+}
+
+void del_chrdev(struct char_device *cdev)
+{
+ int i = cdev->cd_dev - 0x10000;
+
+ unlink_chrdev(cdev);
+ if (cdev->cd_dev >= 0x10000 && i < CHRDEV_NR) {
+ spin_lock(&char_index_lock);
+ clear_bit(i, char_index_bits);
+ spin_unlock(&char_index_lock);
+ }
+ cdput(cdev);
+}
+
int get_chrdev_list(char *page)
{
struct char_device *cdev;
@@ -277,7 +332,7 @@
cdev = cdget(kdev_t_to_nr(dev));
down(&cdev->cd_sem);
- sprintf(buffer, "%s(%d,%d)", cdev->cd_name ? cdev->cd_name : "unknown-char", major(dev), minor(dev));
+ sprintf(buffer, "%s(%ld,%ld)", cdev->cd_name ? cdev->cd_name : "unknown-char", major(dev), minor(dev));
up(&cdev->cd_sem);
return buffer;
diff -ur linux-2.5.67-cdev4/include/linux/fs.h linux-2.5.67-cdev5/include/linux/fs.h
--- linux-2.5.67-cdev4/include/linux/fs.h 2003-04-13 22:46:52.000000000 +0200
+++ linux-2.5.67-cdev5/include/linux/fs.h 2003-04-14 20:41:32.000000000 +0200
@@ -1072,6 +1072,10 @@
extern int chrdev_open(struct inode *, struct file *);
extern struct char_device *cdget(dev_t);
extern void cdput(struct char_device *);
+extern struct char_device *alloc_chrdev(dev_t);
+extern int add_chrdev(struct char_device *, struct file_operations *);
+extern void unlink_chrdev(struct char_device *);
+extern void del_chrdev(struct char_device *);
#define cdget_major(maj) cdget(MKDEV(0, maj))
-
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