Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 660 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
new file mode 100644
index 00000000..84a1fdf6
--- /dev/null
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -0,0 +1,660 @@
+/*
+ * SCSI target lib functions
+ *
+ * Copyright (C) 2005 Mike Christie <michaelc@cs.wisc.edu>
+ * Copyright (C) 2005 FUJITA Tomonori <tomof@acm.org>
+ *
+ * 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 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+#include <linux/blkdev.h>
+#include <linux/hash.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_transport.h>
+#include <scsi/scsi_tgt.h>
+
+#include "scsi_tgt_priv.h"
+
+static struct workqueue_struct *scsi_tgtd;
+static struct kmem_cache *scsi_tgt_cmd_cache;
+
+/*
+ * TODO: this struct will be killed when the block layer supports large bios
+ * and James's work struct code is in
+ */
+struct scsi_tgt_cmd {
+	/* TODO replace work with James b's code */
+	struct work_struct work;
+	/* TODO fix limits of some drivers */
+	struct bio *bio;
+
+	struct list_head hash_list;
+	struct request *rq;
+	u64 itn_id;
+	u64 tag;
+};
+
+#define TGT_HASH_ORDER	4
+#define cmd_hashfn(tag)	hash_long((unsigned long) (tag), TGT_HASH_ORDER)
+
+struct scsi_tgt_queuedata {
+	struct Scsi_Host *shost;
+	struct list_head cmd_hash[1 << TGT_HASH_ORDER];
+	spinlock_t cmd_hash_lock;
+};
+
+/*
+ * Function:	scsi_host_get_command()
+ *
+ * Purpose:	Allocate and setup a scsi command block and blk request
+ *
+ * Arguments:	shost	- scsi host
+ *		data_dir - dma data dir
+ *		gfp_mask- allocator flags
+ *
+ * Returns:	The allocated scsi command structure.
+ *
+ * This should be called by target LLDs to get a command.
+ */
+struct scsi_cmnd *scsi_host_get_command(struct Scsi_Host *shost,
+					enum dma_data_direction data_dir,
+					gfp_t gfp_mask)
+{
+	int write = (data_dir == DMA_TO_DEVICE);
+	struct request *rq;
+	struct scsi_cmnd *cmd;
+	struct scsi_tgt_cmd *tcmd;
+
+	/* Bail if we can't get a reference to the device */
+	if (!get_device(&shost->shost_gendev))
+		return NULL;
+
+	tcmd = kmem_cache_alloc(scsi_tgt_cmd_cache, GFP_ATOMIC);
+	if (!tcmd)
+		goto put_dev;
+
+	/*
+	 * The blk helpers are used to the READ/WRITE requests
+	 * transferring data from a initiator point of view. Since
+	 * we are in target mode we want the opposite.
+	 */
+	rq = blk_get_request(shost->uspace_req_q, !write, gfp_mask);
+	if (!rq)
+		goto free_tcmd;
+
+	cmd = __scsi_get_command(shost, gfp_mask);
+	if (!cmd)
+		goto release_rq;
+
+	cmd->sc_data_direction = data_dir;
+	cmd->jiffies_at_alloc = jiffies;
+	cmd->request = rq;
+
+	cmd->cmnd = rq->cmd;
+
+	rq->special = cmd;
+	rq->cmd_type = REQ_TYPE_SPECIAL;
+	rq->cmd_flags |= REQ_TYPE_BLOCK_PC;
+	rq->end_io_data = tcmd;
+
+	tcmd->rq = rq;
+
+	return cmd;
+
+release_rq:
+	blk_put_request(rq);
+free_tcmd:
+	kmem_cache_free(scsi_tgt_cmd_cache, tcmd);
+put_dev:
+	put_device(&shost->shost_gendev);
+	return NULL;
+
+}
+EXPORT_SYMBOL_GPL(scsi_host_get_command);
+
+/*
+ * Function:	scsi_host_put_command()
+ *
+ * Purpose:	Free a scsi command block
+ *
+ * Arguments:	shost	- scsi host
+ * 		cmd	- command block to free
+ *
+ * Returns:	Nothing.
+ *
+ * Notes:	The command must not belong to any lists.
+ */
+void scsi_host_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
+{
+	struct request_queue *q = shost->uspace_req_q;
+	struct request *rq = cmd->request;
+	struct scsi_tgt_cmd *tcmd = rq->end_io_data;
+	unsigned long flags;
+
+	kmem_cache_free(scsi_tgt_cmd_cache, tcmd);
+
+	spin_lock_irqsave(q->queue_lock, flags);
+	__blk_put_request(q, rq);
+	spin_unlock_irqrestore(q->queue_lock, flags);
+
+	__scsi_put_command(shost, cmd, &shost->shost_gendev);
+}
+EXPORT_SYMBOL_GPL(scsi_host_put_command);
+
+static void cmd_hashlist_del(struct scsi_cmnd *cmd)
+{
+	struct request_queue *q = cmd->request->q;
+	struct scsi_tgt_queuedata *qdata = q->queuedata;
+	unsigned long flags;
+	struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
+
+	spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
+	list_del(&tcmd->hash_list);
+	spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
+}
+
+static void scsi_unmap_user_pages(struct scsi_tgt_cmd *tcmd)
+{
+	blk_rq_unmap_user(tcmd->bio);
+}
+
+static void scsi_tgt_cmd_destroy(struct work_struct *work)
+{
+	struct scsi_tgt_cmd *tcmd =
+		container_of(work, struct scsi_tgt_cmd, work);
+	struct scsi_cmnd *cmd = tcmd->rq->special;
+
+	dprintk("cmd %p %d %u\n", cmd, cmd->sc_data_direction,
+		rq_data_dir(cmd->request));
+	scsi_unmap_user_pages(tcmd);
+	tcmd->rq->bio = NULL;
+	scsi_host_put_command(scsi_tgt_cmd_to_host(cmd), cmd);
+}
+
+static void init_scsi_tgt_cmd(struct request *rq, struct scsi_tgt_cmd *tcmd,
+			      u64 itn_id, u64 tag)
+{
+	struct scsi_tgt_queuedata *qdata = rq->q->queuedata;
+	unsigned long flags;
+	struct list_head *head;
+
+	tcmd->itn_id = itn_id;
+	tcmd->tag = tag;
+	tcmd->bio = NULL;
+	INIT_WORK(&tcmd->work, scsi_tgt_cmd_destroy);
+	spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
+	head = &qdata->cmd_hash[cmd_hashfn(tag)];
+	list_add(&tcmd->hash_list, head);
+	spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
+}
+
+/*
+ * scsi_tgt_alloc_queue - setup queue used for message passing
+ * shost: scsi host
+ *
+ * This should be called by the LLD after host allocation.
+ * And will be released when the host is released.
+ */
+int scsi_tgt_alloc_queue(struct Scsi_Host *shost)
+{
+	struct scsi_tgt_queuedata *queuedata;
+	struct request_queue *q;
+	int err, i;
+
+	/*
+	 * Do we need to send a netlink event or should uspace
+	 * just respond to the hotplug event?
+	 */
+	q = __scsi_alloc_queue(shost, NULL);
+	if (!q)
+		return -ENOMEM;
+
+	queuedata = kzalloc(sizeof(*queuedata), GFP_KERNEL);
+	if (!queuedata) {
+		err = -ENOMEM;
+		goto cleanup_queue;
+	}
+	queuedata->shost = shost;
+	q->queuedata = queuedata;
+
+	/*
+	 * this is a silly hack. We should probably just queue as many
+	 * command as is recvd to userspace. uspace can then make
+	 * sure we do not overload the HBA
+	 */
+	q->nr_requests = shost->can_queue;
+	/*
+	 * We currently only support software LLDs so this does
+	 * not matter for now. Do we need this for the cards we support?
+	 * If so we should make it a host template value.
+	 */
+	blk_queue_dma_alignment(q, 0);
+	shost->uspace_req_q = q;
+
+	for (i = 0; i < ARRAY_SIZE(queuedata->cmd_hash); i++)
+		INIT_LIST_HEAD(&queuedata->cmd_hash[i]);
+	spin_lock_init(&queuedata->cmd_hash_lock);
+
+	return 0;
+
+cleanup_queue:
+	blk_cleanup_queue(q);
+	return err;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_alloc_queue);
+
+void scsi_tgt_free_queue(struct Scsi_Host *shost)
+{
+	int i;
+	unsigned long flags;
+	struct request_queue *q = shost->uspace_req_q;
+	struct scsi_cmnd *cmd;
+	struct scsi_tgt_queuedata *qdata = q->queuedata;
+	struct scsi_tgt_cmd *tcmd, *n;
+	LIST_HEAD(cmds);
+
+	spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
+
+	for (i = 0; i < ARRAY_SIZE(qdata->cmd_hash); i++) {
+		list_for_each_entry_safe(tcmd, n, &qdata->cmd_hash[i],
+					 hash_list)
+			list_move(&tcmd->hash_list, &cmds);
+	}
+
+	spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
+
+	while (!list_empty(&cmds)) {
+		tcmd = list_entry(cmds.next, struct scsi_tgt_cmd, hash_list);
+		list_del(&tcmd->hash_list);
+		cmd = tcmd->rq->special;
+
+		shost->hostt->eh_abort_handler(cmd);
+		scsi_tgt_cmd_destroy(&tcmd->work);
+	}
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_free_queue);
+
+struct Scsi_Host *scsi_tgt_cmd_to_host(struct scsi_cmnd *cmd)
+{
+	struct scsi_tgt_queuedata *queue = cmd->request->q->queuedata;
+	return queue->shost;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_cmd_to_host);
+
+/*
+ * scsi_tgt_queue_command - queue command for userspace processing
+ * @cmd:	scsi command
+ * @scsilun:	scsi lun
+ * @tag:	unique value to identify this command for tmf
+ */
+int scsi_tgt_queue_command(struct scsi_cmnd *cmd, u64 itn_id,
+			   struct scsi_lun *scsilun, u64 tag)
+{
+	struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
+	int err;
+
+	init_scsi_tgt_cmd(cmd->request, tcmd, itn_id, tag);
+	err = scsi_tgt_uspace_send_cmd(cmd, itn_id, scsilun, tag);
+	if (err)
+		cmd_hashlist_del(cmd);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_queue_command);
+
+/*
+ * This is run from a interrupt handler normally and the unmap
+ * needs process context so we must queue
+ */
+static void scsi_tgt_cmd_done(struct scsi_cmnd *cmd)
+{
+	struct scsi_tgt_cmd *tcmd = cmd->request->end_io_data;
+
+	dprintk("cmd %p %u\n", cmd, rq_data_dir(cmd->request));
+
+	scsi_tgt_uspace_send_status(cmd, tcmd->itn_id, tcmd->tag);
+
+	scsi_release_buffers(cmd);
+
+	queue_work(scsi_tgtd, &tcmd->work);
+}
+
+static int scsi_tgt_transfer_response(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *shost = scsi_tgt_cmd_to_host(cmd);
+	int err;
+
+	dprintk("cmd %p %u\n", cmd, rq_data_dir(cmd->request));
+
+	err = shost->hostt->transfer_response(cmd, scsi_tgt_cmd_done);
+	switch (err) {
+	case SCSI_MLQUEUE_HOST_BUSY:
+	case SCSI_MLQUEUE_DEVICE_BUSY:
+		return -EAGAIN;
+	}
+	return 0;
+}
+
+/* TODO: test this crap and replace bio_map_user with new interface maybe */
+static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd,
+			       unsigned long uaddr, unsigned int len, int rw)
+{
+	struct request_queue *q = cmd->request->q;
+	struct request *rq = cmd->request;
+	int err;
+
+	dprintk("%lx %u\n", uaddr, len);
+	err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL);
+	if (err) {
+		/*
+		 * TODO: need to fixup sg_tablesize, max_segment_size,
+		 * max_sectors, etc for modern HW and software drivers
+		 * where this value is bogus.
+		 *
+		 * TODO2: we can alloc a reserve buffer of max size
+		 * we can handle and do the slow copy path for really large
+		 * IO.
+		 */
+		eprintk("Could not handle request of size %u.\n", len);
+		return err;
+	}
+
+	tcmd->bio = rq->bio;
+	err = scsi_init_io(cmd, GFP_KERNEL);
+	if (err) {
+		scsi_release_buffers(cmd);
+		goto unmap_rq;
+	}
+	/*
+	 * we use REQ_TYPE_BLOCK_PC so scsi_init_io doesn't set the
+	 * length for us.
+	 */
+	cmd->sdb.length = blk_rq_bytes(rq);
+
+	return 0;
+
+unmap_rq:
+	scsi_unmap_user_pages(tcmd);
+	return err;
+}
+
+static int scsi_tgt_copy_sense(struct scsi_cmnd *cmd, unsigned long uaddr,
+				unsigned len)
+{
+	char __user *p = (char __user *) uaddr;
+
+	if (copy_from_user(cmd->sense_buffer, p,
+			   min_t(unsigned, SCSI_SENSE_BUFFERSIZE, len))) {
+		printk(KERN_ERR "Could not copy the sense buffer\n");
+		return -EIO;
+	}
+	return 0;
+}
+
+static int scsi_tgt_abort_cmd(struct Scsi_Host *shost, struct scsi_cmnd *cmd)
+{
+	struct scsi_tgt_cmd *tcmd;
+	int err;
+
+	err = shost->hostt->eh_abort_handler(cmd);
+	if (err)
+		eprintk("fail to abort %p\n", cmd);
+
+	tcmd = cmd->request->end_io_data;
+	scsi_tgt_cmd_destroy(&tcmd->work);
+	return err;
+}
+
+static struct request *tgt_cmd_hash_lookup(struct request_queue *q, u64 tag)
+{
+	struct scsi_tgt_queuedata *qdata = q->queuedata;
+	struct request *rq = NULL;
+	struct list_head *head;
+	struct scsi_tgt_cmd *tcmd;
+	unsigned long flags;
+
+	head = &qdata->cmd_hash[cmd_hashfn(tag)];
+	spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
+	list_for_each_entry(tcmd, head, hash_list) {
+		if (tcmd->tag == tag) {
+			rq = tcmd->rq;
+			list_del(&tcmd->hash_list);
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
+
+	return rq;
+}
+
+int scsi_tgt_kspace_exec(int host_no, u64 itn_id, int result, u64 tag,
+			 unsigned long uaddr, u32 len, unsigned long sense_uaddr,
+			 u32 sense_len, u8 rw)
+{
+	struct Scsi_Host *shost;
+	struct scsi_cmnd *cmd;
+	struct request *rq;
+	struct scsi_tgt_cmd *tcmd;
+	int err = 0;
+
+	dprintk("%d %llu %d %u %lx %u\n", host_no, (unsigned long long) tag,
+		result, len, uaddr, rw);
+
+	/* TODO: replace with a O(1) alg */
+	shost = scsi_host_lookup(host_no);
+	if (!shost) {
+		printk(KERN_ERR "Could not find host no %d\n", host_no);
+		return -EINVAL;
+	}
+
+	if (!shost->uspace_req_q) {
+		printk(KERN_ERR "Not target scsi host %d\n", host_no);
+		goto done;
+	}
+
+	rq = tgt_cmd_hash_lookup(shost->uspace_req_q, tag);
+	if (!rq) {
+		printk(KERN_ERR "Could not find tag %llu\n",
+		       (unsigned long long) tag);
+		err = -EINVAL;
+		goto done;
+	}
+	cmd = rq->special;
+
+	dprintk("cmd %p scb %x result %d len %d bufflen %u %u %x\n",
+		cmd, cmd->cmnd[0], result, len, scsi_bufflen(cmd),
+		rq_data_dir(rq), cmd->cmnd[0]);
+
+	if (result == TASK_ABORTED) {
+		scsi_tgt_abort_cmd(shost, cmd);
+		goto done;
+	}
+	/*
+	 * store the userspace values here, the working values are
+	 * in the request_* values
+	 */
+	tcmd = cmd->request->end_io_data;
+	cmd->result = result;
+
+	if (cmd->result == SAM_STAT_CHECK_CONDITION)
+		scsi_tgt_copy_sense(cmd, sense_uaddr, sense_len);
+
+	if (len) {
+		err = scsi_map_user_pages(rq->end_io_data, cmd, uaddr, len, rw);
+		if (err) {
+			/*
+			 * user-space daemon bugs or OOM
+			 * TODO: we can do better for OOM.
+			 */
+			struct scsi_tgt_queuedata *qdata;
+			struct list_head *head;
+			unsigned long flags;
+
+			eprintk("cmd %p ret %d uaddr %lx len %d rw %d\n",
+				cmd, err, uaddr, len, rw);
+
+			qdata = shost->uspace_req_q->queuedata;
+			head = &qdata->cmd_hash[cmd_hashfn(tcmd->tag)];
+
+			spin_lock_irqsave(&qdata->cmd_hash_lock, flags);
+			list_add(&tcmd->hash_list, head);
+			spin_unlock_irqrestore(&qdata->cmd_hash_lock, flags);
+
+			goto done;
+		}
+	}
+	err = scsi_tgt_transfer_response(cmd);
+done:
+	scsi_host_put(shost);
+	return err;
+}
+
+int scsi_tgt_tsk_mgmt_request(struct Scsi_Host *shost, u64 itn_id,
+			      int function, u64 tag, struct scsi_lun *scsilun,
+			      void *data)
+{
+	int err;
+
+	/* TODO: need to retry if this fails. */
+	err = scsi_tgt_uspace_send_tsk_mgmt(shost->host_no, itn_id,
+					    function, tag, scsilun, data);
+	if (err < 0)
+		eprintk("The task management request lost!\n");
+	return err;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_tsk_mgmt_request);
+
+int scsi_tgt_kspace_tsk_mgmt(int host_no, u64 itn_id, u64 mid, int result)
+{
+	struct Scsi_Host *shost;
+	int err = -EINVAL;
+
+	dprintk("%d %d %llx\n", host_no, result, (unsigned long long) mid);
+
+	shost = scsi_host_lookup(host_no);
+	if (!shost) {
+		printk(KERN_ERR "Could not find host no %d\n", host_no);
+		return err;
+	}
+
+	if (!shost->uspace_req_q) {
+		printk(KERN_ERR "Not target scsi host %d\n", host_no);
+		goto done;
+	}
+
+	err = shost->transportt->tsk_mgmt_response(shost, itn_id, mid, result);
+done:
+	scsi_host_put(shost);
+	return err;
+}
+
+int scsi_tgt_it_nexus_create(struct Scsi_Host *shost, u64 itn_id,
+			     char *initiator)
+{
+	int err;
+
+	/* TODO: need to retry if this fails. */
+	err = scsi_tgt_uspace_send_it_nexus_request(shost->host_no, itn_id, 0,
+						    initiator);
+	if (err < 0)
+		eprintk("The i_t_neuxs request lost, %d %llx!\n",
+			shost->host_no, (unsigned long long)itn_id);
+	return err;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_it_nexus_create);
+
+int scsi_tgt_it_nexus_destroy(struct Scsi_Host *shost, u64 itn_id)
+{
+	int err;
+
+	/* TODO: need to retry if this fails. */
+	err = scsi_tgt_uspace_send_it_nexus_request(shost->host_no,
+						    itn_id, 1, NULL);
+	if (err < 0)
+		eprintk("The i_t_neuxs request lost, %d %llx!\n",
+			shost->host_no, (unsigned long long)itn_id);
+	return err;
+}
+EXPORT_SYMBOL_GPL(scsi_tgt_it_nexus_destroy);
+
+int scsi_tgt_kspace_it_nexus_rsp(int host_no, u64 itn_id, int result)
+{
+	struct Scsi_Host *shost;
+	int err = -EINVAL;
+
+	dprintk("%d %d%llx\n", host_no, result, (unsigned long long)itn_id);
+
+	shost = scsi_host_lookup(host_no);
+	if (!shost) {
+		printk(KERN_ERR "Could not find host no %d\n", host_no);
+		return err;
+	}
+
+	if (!shost->uspace_req_q) {
+		printk(KERN_ERR "Not target scsi host %d\n", host_no);
+		goto done;
+	}
+
+	err = shost->transportt->it_nexus_response(shost, itn_id, result);
+done:
+	scsi_host_put(shost);
+	return err;
+}
+
+static int __init scsi_tgt_init(void)
+{
+	int err;
+
+	scsi_tgt_cmd_cache =  KMEM_CACHE(scsi_tgt_cmd, 0);
+	if (!scsi_tgt_cmd_cache)
+		return -ENOMEM;
+
+	scsi_tgtd = alloc_workqueue("scsi_tgtd", 0, 1);
+	if (!scsi_tgtd) {
+		err = -ENOMEM;
+		goto free_kmemcache;
+	}
+
+	err = scsi_tgt_if_init();
+	if (err)
+		goto destroy_wq;
+
+	return 0;
+
+destroy_wq:
+	destroy_workqueue(scsi_tgtd);
+free_kmemcache:
+	kmem_cache_destroy(scsi_tgt_cmd_cache);
+	return err;
+}
+
+static void __exit scsi_tgt_exit(void)
+{
+	destroy_workqueue(scsi_tgtd);
+	scsi_tgt_if_exit();
+	kmem_cache_destroy(scsi_tgt_cmd_cache);
+}
+
+module_init(scsi_tgt_init);
+module_exit(scsi_tgt_exit);
+
+MODULE_DESCRIPTION("SCSI target core");
+MODULE_LICENSE("GPL");