[SCSI] gdth: Move members from SCp to gdth_cmndinfo, stage 2
[cascardo/linux.git] / drivers / scsi / sg.c
index 570977c..f6f5fc7 100644 (file)
@@ -41,9 +41,9 @@ static int sg_version_num = 30534;    /* 2 digits for each component */
 #include <linux/fcntl.h>
 #include <linux/init.h>
 #include <linux/poll.h>
-#include <linux/smp_lock.h>
 #include <linux/moduleparam.h>
 #include <linux/cdev.h>
+#include <linux/idr.h>
 #include <linux/seq_file.h>
 #include <linux/blkdev.h>
 #include <linux/delay.h>
@@ -100,12 +100,11 @@ static int scatter_elem_sz_prev = SG_SCATTER_SZ;
 #define SG_SECTOR_SZ 512
 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1)
 
-#define SG_DEV_ARR_LUMP 32     /* amount to over allocate sg_dev_arr by */
-
 static int sg_add(struct class_device *, struct class_interface *);
 static void sg_remove(struct class_device *, struct class_interface *);
 
-static DEFINE_RWLOCK(sg_dev_arr_lock); /* Also used to lock
+static DEFINE_IDR(sg_index_idr);
+static DEFINE_RWLOCK(sg_index_lock);   /* Also used to lock
                                                           file descriptor list for device */
 
 static struct class_interface sg_interface = {
@@ -115,7 +114,7 @@ static struct class_interface sg_interface = {
 
 typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */
        unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */
-       unsigned short sglist_len; /* size of malloc'd scatter-gather list ++ */
+       unsigned 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 */
        struct scatterlist *buffer;/* scatter list */
@@ -163,6 +162,7 @@ typedef struct sg_device { /* holds the state of each scsi generic device */
        struct 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 */
+       u32 index;              /* device index number */
        Sg_fd *headfp;          /* first open fd belonging to this device */
        volatile char detached; /* 0->attached, 1->detached pending removal */
        volatile char exclude;  /* opened for exclusive access */
@@ -210,10 +210,6 @@ static Sg_device *sg_get_dev(int dev);
 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)
 #define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)
 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
@@ -1332,40 +1328,35 @@ static struct class *sg_sysfs_class;
 
 static int sg_sysfs_valid = 0;
 
-static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
+static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
 {
        struct request_queue *q = scsidp->request_queue;
        Sg_device *sdp;
        unsigned long iflags;
-       void *old_sg_dev_arr = NULL;
-       int k, error;
+       int error;
+       u32 k;
 
        sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);
        if (!sdp) {
                printk(KERN_WARNING "kmalloc Sg_device failure\n");
-               return -ENOMEM;
+               return ERR_PTR(-ENOMEM);
+       }
+       error = -ENOMEM;
+       if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
+               printk(KERN_WARNING "idr expansion Sg_device failure\n");
+               goto out;
        }
 
-       write_lock_irqsave(&sg_dev_arr_lock, iflags);
-       if (unlikely(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 = kzalloc(tmp_dev_max * sizeof(Sg_device *), GFP_KERNEL);
-               if (unlikely(!tmp_da))
-                       goto expand_failed;
+       write_lock_irqsave(&sg_index_lock, iflags);
+       error = idr_get_new(&sg_index_idr, sdp, &k);
+       write_unlock_irqrestore(&sg_index_lock, iflags);
 
-               write_lock_irqsave(&sg_dev_arr_lock, iflags);
-               memcpy(tmp_da, sg_dev_arr, sg_dev_max * sizeof(Sg_device *));
-               old_sg_dev_arr = sg_dev_arr;
-               sg_dev_arr = tmp_da;
-               sg_dev_max = tmp_dev_max;
+       if (error) {
+               printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
+                      error);
+               goto out;
        }
 
-       for (k = 0; k < sg_dev_max; k++)
-               if (!sg_dev_arr[k])
-                       break;
        if (unlikely(k >= SG_MAX_DEVS))
                goto overflow;
 
@@ -1376,25 +1367,17 @@ static int sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
        sdp->device = scsidp;
        init_waitqueue_head(&sdp->o_excl_wait);
        sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments);
+       sdp->index = k;
 
-       sg_nr_dev++;
-       sg_dev_arr[k] = sdp;
-       write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
-       error = k;
-
+       error = 0;
  out:
-       if (error < 0)
+       if (error) {
                kfree(sdp);
-       kfree(old_sg_dev_arr);
-       return error;
-
- expand_failed:
-       printk(KERN_WARNING "sg_alloc: device array cannot be resized\n");
-       error = -ENOMEM;
-       goto out;
+               return ERR_PTR(error);
+       }
+       return sdp;
 
  overflow:
-       write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
        sdev_printk(KERN_WARNING, scsidp,
                    "Unable to attach sg device type=%d, minor "
                    "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
@@ -1409,7 +1392,7 @@ sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
        struct gendisk *disk;
        Sg_device *sdp = NULL;
        struct cdev * cdev = NULL;
-       int error, k;
+       int error;
        unsigned long iflags;
 
        disk = alloc_disk(1);
@@ -1428,15 +1411,15 @@ sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
        cdev->owner = THIS_MODULE;
        cdev->ops = &sg_fops;
 
-       error = sg_alloc(disk, scsidp);
-       if (error < 0) {
+       sdp = sg_alloc(disk, scsidp);
+       if (IS_ERR(sdp)) {
                printk(KERN_WARNING "sg_alloc failed\n");
+               error = PTR_ERR(sdp);
                goto out;
        }
-       k = error;
-       sdp = sg_dev_arr[k];
 
-       error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, k), 1);
+       class_set_devdata(cl_dev, sdp);
+       error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);
        if (error)
                goto cdev_add_err;
 
@@ -1445,8 +1428,8 @@ sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
                struct class_device * sg_class_member;
 
                sg_class_member = class_device_create(sg_sysfs_class, NULL,
-                               MKDEV(SCSI_GENERIC_MAJOR, k), 
-                               cl_dev->dev, "%s", 
+                               MKDEV(SCSI_GENERIC_MAJOR, sdp->index),
+                               cl_dev->dev, "%s",
                                disk->disk_name);
                if (IS_ERR(sg_class_member))
                        printk(KERN_WARNING "sg_add: "
@@ -1456,21 +1439,21 @@ sg_add(struct class_device *cl_dev, struct class_interface *cl_intf)
                                          &sg_class_member->kobj, "generic");
                if (error)
                        printk(KERN_ERR "sg_add: unable to make symlink "
-                                       "'generic' back to sg%d\n", k);
+                                       "'generic' back to sg%d\n", sdp->index);
        } else
-               printk(KERN_WARNING "sg_add: sg_sys INvalid\n");
+               printk(KERN_WARNING "sg_add: sg_sys Invalid\n");
 
        sdev_printk(KERN_NOTICE, scsidp,
-                   "Attached scsi generic sg%d type %d\n", k,scsidp->type);
+                   "Attached scsi generic sg%d type %d\n", sdp->index,
+                   scsidp->type);
 
        return 0;
 
 cdev_add_err:
-       write_lock_irqsave(&sg_dev_arr_lock, iflags);
-       kfree(sg_dev_arr[k]);
-       sg_dev_arr[k] = NULL;
-       sg_nr_dev--;
-       write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+       write_lock_irqsave(&sg_index_lock, iflags);
+       idr_remove(&sg_index_idr, sdp->index);
+       write_unlock_irqrestore(&sg_index_lock, iflags);
+       kfree(sdp);
 
 out:
        put_disk(disk);
@@ -1483,64 +1466,56 @@ static void
 sg_remove(struct class_device *cl_dev, struct class_interface *cl_intf)
 {
        struct scsi_device *scsidp = to_scsi_device(cl_dev->dev);
-       Sg_device *sdp = NULL;
+       Sg_device *sdp = class_get_devdata(cl_dev);
        unsigned long iflags;
        Sg_fd *sfp;
        Sg_fd *tsfp;
        Sg_request *srp;
        Sg_request *tsrp;
-       int k, delay;
+       int delay;
 
-       if (NULL == sg_dev_arr)
+       if (!sdp)
                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 */
-               if (sdp->headfp) {
-                       sdp->detached = 1;
-                       for (sfp = sdp->headfp; sfp; sfp = tsfp) {
-                               tsfp = sfp->nextfp;
-                               for (srp = sfp->headrp; srp; srp = tsrp) {
-                                       tsrp = srp->nextrp;
-                                       if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
-                                               sg_finish_rem_req(srp);
-                               }
-                               if (sfp->closed) {
-                                       scsi_device_put(sdp->device);
-                                       __sg_remove_sfp(sdp, sfp);
-                               } else {
-                                       delay = 1;
-                                       wake_up_interruptible(&sfp->read_wait);
-                                       kill_fasync(&sfp->async_qp, SIGPOLL,
-                                                   POLL_HUP);
-                               }
+       write_lock_irqsave(&sg_index_lock, iflags);
+       if (sdp->headfp) {
+               sdp->detached = 1;
+               for (sfp = sdp->headfp; sfp; sfp = tsfp) {
+                       tsfp = sfp->nextfp;
+                       for (srp = sfp->headrp; srp; srp = tsrp) {
+                               tsrp = srp->nextrp;
+                               if (sfp->closed || (0 == sg_srp_done(srp, sfp)))
+                                       sg_finish_rem_req(srp);
                        }
-                       SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", k));
-                       if (NULL == sdp->headfp) {
-                               sg_dev_arr[k] = NULL;
+                       if (sfp->closed) {
+                               scsi_device_put(sdp->device);
+                               __sg_remove_sfp(sdp, sfp);
+                       } else {
+                               delay = 1;
+                               wake_up_interruptible(&sfp->read_wait);
+                               kill_fasync(&sfp->async_qp, SIGPOLL,
+                                           POLL_HUP);
                        }
-               } else {        /* nothing active, simple case */
-                       SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", k));
-                       sg_dev_arr[k] = NULL;
                }
-               sg_nr_dev--;
-               break;
-       }
-       write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
-
-       if (sdp) {
-               sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
-               class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, k));
-               cdev_del(sdp->cdev);
-               sdp->cdev = NULL;
-               put_disk(sdp->disk);
-               sdp->disk = NULL;
-               if (NULL == sdp->headfp)
-                       kfree((char *) sdp);
-       }
+               SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d, dirty\n", sdp->index));
+               if (NULL == sdp->headfp) {
+                       idr_remove(&sg_index_idr, sdp->index);
+               }
+       } else {        /* nothing active, simple case */
+               SCSI_LOG_TIMEOUT(3, printk("sg_remove: dev=%d\n", sdp->index));
+               idr_remove(&sg_index_idr, sdp->index);
+       }
+       write_unlock_irqrestore(&sg_index_lock, iflags);
+
+       sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
+       class_device_destroy(sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));
+       cdev_del(sdp->cdev);
+       sdp->cdev = NULL;
+       put_disk(sdp->disk);
+       sdp->disk = NULL;
+       if (NULL == sdp->headfp)
+               kfree(sdp);
 
        if (delay)
                msleep(10);     /* dirty detach so delay device destruction */
@@ -1610,9 +1585,7 @@ exit_sg(void)
        sg_sysfs_valid = 0;
        unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),
                                 SG_MAX_DEVS);
-       kfree((char *)sg_dev_arr);
-       sg_dev_arr = NULL;
-       sg_dev_max = 0;
+       idr_destroy(&sg_index_idr);
 }
 
 static int
@@ -1843,7 +1816,7 @@ sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
        int blk_size = buff_size;
        struct page *p = NULL;
 
-       if ((blk_size < 0) || (!sfp))
+       if (blk_size < 0)
                return -EFAULT;
        if (0 == blk_size)
                ++blk_size;     /* don't know why */
@@ -2332,10 +2305,10 @@ sg_get_nth_sfp(Sg_device * sdp, int nth)
        unsigned long iflags;
        int k;
 
-       read_lock_irqsave(&sg_dev_arr_lock, iflags);
+       read_lock_irqsave(&sg_index_lock, iflags);
        for (k = 0, resp = sdp->headfp; resp && (k < nth);
             ++k, resp = resp->nextfp) ;
-       read_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+       read_unlock_irqrestore(&sg_index_lock, iflags);
        return resp;
 }
 #endif
@@ -2362,7 +2335,7 @@ sg_add_sfp(Sg_device * sdp, int dev)
        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);
+       write_lock_irqsave(&sg_index_lock, iflags);
        if (!sdp->headfp)
                sdp->headfp = sfp;
        else {                  /* add to tail of existing list */
@@ -2371,7 +2344,7 @@ sg_add_sfp(Sg_device * sdp, int dev)
                        pfp = pfp->nextfp;
                pfp->nextfp = sfp;
        }
-       write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+       write_unlock_irqrestore(&sg_index_lock, iflags);
        SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: sfp=0x%p\n", sfp));
        if (unlikely(sg_big_buff != def_reserved_size))
                sg_big_buff = def_reserved_size;
@@ -2432,22 +2405,14 @@ sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp)
        if (0 == dirty) {
                unsigned long iflags;
 
-               write_lock_irqsave(&sg_dev_arr_lock, iflags);
+               write_lock_irqsave(&sg_index_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;
-                       kfree((char *) sdp);
+                       idr_remove(&sg_index_idr, sdp->index);
+                       kfree(sdp);
                        res = 1;
                }
-               write_unlock_irqrestore(&sg_dev_arr_lock, iflags);
+               write_unlock_irqrestore(&sg_index_lock, iflags);
        } else {
                /* MOD_INC's to inhibit unloading sg and associated adapter driver */
                /* only bump the access_count if we actually succeeded in
@@ -2546,17 +2511,26 @@ sg_allow_access(unsigned char opcode, char dev_type)
 }
 
 #ifdef CONFIG_SCSI_PROC_FS
+static int
+sg_idr_max_id(int id, void *p, void *data)
+{
+       int *k = data;
+
+       if (*k < id)
+               *k = id;
+
+       return 0;
+}
+
 static int
 sg_last_dev(void)
 {
-       int k;
+       int k = 0;
        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);
+       read_lock_irqsave(&sg_index_lock, iflags);
+       idr_for_each(&sg_index_idr, sg_idr_max_id, &k);
+       read_unlock_irqrestore(&sg_index_lock, iflags);
        return k + 1;           /* origin 1 */
 }
 #endif
@@ -2564,15 +2538,13 @@ sg_last_dev(void)
 static Sg_device *
 sg_get_dev(int dev)
 {
-       Sg_device *sdp = NULL;
+       Sg_device *sdp;
        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);
-       }
+       read_lock_irqsave(&sg_index_lock, iflags);
+       sdp = idr_find(&sg_index_idr, dev);
+       read_unlock_irqrestore(&sg_index_lock, iflags);
+
        return sdp;
 }
 
@@ -2806,8 +2778,6 @@ static void * dev_seq_start(struct seq_file *s, loff_t *pos)
        if (! it)
                return NULL;
 
-       if (NULL == sg_dev_arr)
-               return NULL;
        it->index = *pos;
        it->max = sg_last_dev();
        if (it->index >= it->max)
@@ -2943,8 +2913,8 @@ static int sg_proc_seq_show_debug(struct seq_file *s, void *v)
        Sg_device *sdp;
 
        if (it && (0 == it->index)) {
-               seq_printf(s, "dev_max(currently)=%d max_active_device=%d "
-                          "(origin 1)\n", sg_dev_max, (int)it->max);
+               seq_printf(s, "max_active_device=%d(origin 1)\n",
+                          (int)it->max);
                seq_printf(s, " def_reserved_size=%d\n", sg_big_buff);
        }
        sdp = it ? sg_get_dev(it->index) : NULL;