From: Christoph Hellwig Date: Sat, 10 Jun 2006 16:01:03 +0000 (+0200) Subject: [SCSI] remove scsi_request infrastructure X-Git-Tag: v2.6.18-rc1~1092^2~8 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=beb40487508290f5d6565598c60a3f44261beef2;p=linux-2.6 [SCSI] remove scsi_request infrastructure With Achim patch the last user (gdth) is switched away from scsi_request so we an kill it now. Also disables some code in i2o_scsi that was broken since the sg driver stopped using scsi_requests. Signed-off-by: Christoph Hellwig Signed-off-by: James Bottomley --- diff --git a/drivers/message/i2o/i2o_scsi.c b/drivers/message/i2o/i2o_scsi.c index c08ddac371..6ebf38213f 100644 --- a/drivers/message/i2o/i2o_scsi.c +++ b/drivers/message/i2o/i2o_scsi.c @@ -65,9 +65,7 @@ #include #include #include -#include #include -#include #define OSM_NAME "scsi-osm" #define OSM_VERSION "1.316" @@ -588,6 +586,7 @@ static int i2o_scsi_queuecommand(struct scsi_cmnd *SCpnt, mptr = &msg->body[0]; +#if 0 /* this code can't work */ #ifdef CONFIG_I2O_EXT_ADAPTEC if (c->adaptec) { u32 adpt_flags = 0; @@ -624,6 +623,7 @@ static int i2o_scsi_queuecommand(struct scsi_cmnd *SCpnt, *mptr++ = cpu_to_le32(I2O_VENDOR_DPT << 16 | I2O_CMD_SCSI_EXEC); *mptr++ = cpu_to_le32(adpt_flags | tid); } +#endif #endif msg->u.head[1] = cpu_to_le32(cmd | HOST_TID << 12 | tid); diff --git a/drivers/scsi/constants.c b/drivers/scsi/constants.c index e24835b38b..d92d5040a9 100644 --- a/drivers/scsi/constants.c +++ b/drivers/scsi/constants.c @@ -13,9 +13,9 @@ #include #include +#include #include #include -#include #include #include @@ -1261,16 +1261,6 @@ void scsi_print_sense(const char *devclass, struct scsi_cmnd *cmd) } EXPORT_SYMBOL(scsi_print_sense); -void scsi_print_req_sense(const char *devclass, struct scsi_request *sreq) -{ - const char *name = devclass; - - if (sreq->sr_request->rq_disk) - name = sreq->sr_request->rq_disk->disk_name; - __scsi_print_sense(name, sreq->sr_sense_buffer, SCSI_SENSE_BUFFERSIZE); -} -EXPORT_SYMBOL(scsi_print_req_sense); - void scsi_print_command(struct scsi_cmnd *cmd) { /* Assume appended output (i.e. not at start of line) */ diff --git a/drivers/scsi/gdth.c b/drivers/scsi/gdth.c index fc4d9f61cf..76071a1583 100644 --- a/drivers/scsi/gdth.c +++ b/drivers/scsi/gdth.c @@ -716,8 +716,8 @@ static void gdth_scsi_done(struct scsi_cmnd *scp) { TRACE2(("gdth_scsi_done()\n")); - if (scp->sc_request) - complete((struct completion *)scp->sc_request); + if (scp->request) + complete((struct completion *)scp->request); } int __gdth_execute(struct scsi_device *sdev, gdth_cmd_str *gdtcmd, char *cmnd, @@ -732,8 +732,8 @@ int __gdth_execute(struct scsi_device *sdev, gdth_cmd_str *gdtcmd, char *cmnd, return -ENOMEM; memset(scp, 0, sizeof(*scp)); scp->device = sdev; - /* use sc_request field to save the ptr. to completion struct. */ - scp->sc_request = (struct scsi_request *)&wait; + /* use request field to save the ptr. to completion struct. */ + scp->request = (struct request *)&wait; scp->timeout_per_command = timeout*HZ; scp->request_buffer = gdtcmd; scp->cmd_len = 12; diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index 8b80e59c8c..96b65b307d 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -79,7 +79,6 @@ #include #include #include -#include #include "ipr.h" /* diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c index 994015726e..f1e129b7c9 100644 --- a/drivers/scsi/libata-scsi.c +++ b/drivers/scsi/libata-scsi.c @@ -38,9 +38,9 @@ #include #include #include +#include #include #include -#include #include #include #include diff --git a/drivers/scsi/qlogicpti.c b/drivers/scsi/qlogicpti.c index 00f4b84636..417a121fcd 100644 --- a/drivers/scsi/qlogicpti.c +++ b/drivers/scsi/qlogicpti.c @@ -43,7 +43,6 @@ #include #include #include -#include #include #include diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 73994e2ac2..3e90ba797d 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -63,7 +63,6 @@ #include #include #include -#include #include "scsi_priv.h" #include "scsi_logging.h" @@ -116,79 +115,6 @@ const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE] = { }; EXPORT_SYMBOL(scsi_device_types); -/* - * Function: scsi_allocate_request - * - * Purpose: Allocate a request descriptor. - * - * Arguments: device - device for which we want a request - * gfp_mask - allocation flags passed to kmalloc - * - * Lock status: No locks assumed to be held. This function is SMP-safe. - * - * Returns: Pointer to request block. - */ -struct scsi_request *scsi_allocate_request(struct scsi_device *sdev, - gfp_t gfp_mask) -{ - const int offset = ALIGN(sizeof(struct scsi_request), 4); - const int size = offset + sizeof(struct request); - struct scsi_request *sreq; - - sreq = kzalloc(size, gfp_mask); - if (likely(sreq != NULL)) { - sreq->sr_request = (struct request *)(((char *)sreq) + offset); - sreq->sr_device = sdev; - sreq->sr_host = sdev->host; - sreq->sr_magic = SCSI_REQ_MAGIC; - sreq->sr_data_direction = DMA_BIDIRECTIONAL; - } - - return sreq; -} -EXPORT_SYMBOL(scsi_allocate_request); - -void __scsi_release_request(struct scsi_request *sreq) -{ - struct request *req = sreq->sr_request; - - /* unlikely because the tag was usually ended earlier by the - * mid-layer. However, for layering reasons ULD's don't end - * the tag of commands they generate. */ - if (unlikely(blk_rq_tagged(req))) { - unsigned long flags; - struct request_queue *q = req->q; - - spin_lock_irqsave(q->queue_lock, flags); - blk_queue_end_tag(q, req); - spin_unlock_irqrestore(q->queue_lock, flags); - } - - - if (likely(sreq->sr_command != NULL)) { - struct scsi_cmnd *cmd = sreq->sr_command; - - sreq->sr_command = NULL; - scsi_next_command(cmd); - } -} - -/* - * Function: scsi_release_request - * - * Purpose: Release a request descriptor. - * - * Arguments: sreq - request to release - * - * Lock status: No locks assumed to be held. This function is SMP-safe. - */ -void scsi_release_request(struct scsi_request *sreq) -{ - __scsi_release_request(sreq); - kfree(sreq); -} -EXPORT_SYMBOL(scsi_release_request); - struct scsi_host_cmd_pool { kmem_cache_t *slab; unsigned int users; @@ -646,73 +572,6 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) return rtn; } -/* - * Function: scsi_init_cmd_from_req - * - * Purpose: Queue a SCSI command - * Purpose: Initialize a struct scsi_cmnd from a struct scsi_request - * - * Arguments: cmd - command descriptor. - * sreq - Request from the queue. - * - * Lock status: None needed. - * - * Returns: Nothing. - * - * Notes: Mainly transfer data from the request structure to the - * command structure. The request structure is allocated - * using the normal memory allocator, and requests can pile - * up to more or less any depth. The command structure represents - * a consumable resource, as these are allocated into a pool - * when the SCSI subsystem initializes. The preallocation is - * required so that in low-memory situations a disk I/O request - * won't cause the memory manager to try and write out a page. - * The request structure is generally used by ioctls and character - * devices. - */ -void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, struct scsi_request *sreq) -{ - sreq->sr_command = cmd; - - cmd->cmd_len = sreq->sr_cmd_len; - cmd->use_sg = sreq->sr_use_sg; - - cmd->request = sreq->sr_request; - memcpy(cmd->data_cmnd, sreq->sr_cmnd, sizeof(cmd->data_cmnd)); - cmd->serial_number = 0; - cmd->bufflen = sreq->sr_bufflen; - cmd->buffer = sreq->sr_buffer; - cmd->retries = 0; - cmd->allowed = sreq->sr_allowed; - cmd->done = sreq->sr_done; - cmd->timeout_per_command = sreq->sr_timeout_per_command; - cmd->sc_data_direction = sreq->sr_data_direction; - cmd->sglist_len = sreq->sr_sglist_len; - cmd->underflow = sreq->sr_underflow; - cmd->sc_request = sreq; - memcpy(cmd->cmnd, sreq->sr_cmnd, sizeof(sreq->sr_cmnd)); - - /* - * Zero the sense buffer. Some host adapters automatically request - * sense on error. 0 is not a valid sense code. - */ - memset(cmd->sense_buffer, 0, sizeof(sreq->sr_sense_buffer)); - cmd->request_buffer = sreq->sr_buffer; - cmd->request_bufflen = sreq->sr_bufflen; - cmd->old_use_sg = cmd->use_sg; - if (cmd->cmd_len == 0) - cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]); - cmd->old_cmd_len = cmd->cmd_len; - cmd->sc_old_data_direction = cmd->sc_data_direction; - cmd->old_underflow = cmd->underflow; - - /* - * Start the timer ticking. - */ - cmd->result = 0; - - SCSI_LOG_MLQUEUE(3, printk("Leaving scsi_init_cmd_from_req()\n")); -} /* * Per-CPU I/O completion queue. @@ -809,7 +668,6 @@ void scsi_finish_command(struct scsi_cmnd *cmd) { struct scsi_device *sdev = cmd->device; struct Scsi_Host *shost = sdev->host; - struct scsi_request *sreq; scsi_device_unbusy(sdev); @@ -839,21 +697,6 @@ void scsi_finish_command(struct scsi_cmnd *cmd) * We can get here with use_sg=0, causing a panic in the upper level */ cmd->use_sg = cmd->old_use_sg; - - /* - * If there is an associated request structure, copy the data over - * before we call the completion function. - */ - sreq = cmd->sc_request; - if (sreq) { - sreq->sr_result = sreq->sr_command->result; - if (sreq->sr_result) { - memcpy(sreq->sr_sense_buffer, - sreq->sr_command->sense_buffer, - sizeof(sreq->sr_sense_buffer)); - } - } - cmd->done(cmd); } EXPORT_SYMBOL(scsi_finish_command); diff --git a/drivers/scsi/scsi.h b/drivers/scsi/scsi.h index 5ee5d80a99..f51e466893 100644 --- a/drivers/scsi/scsi.h +++ b/drivers/scsi/scsi.h @@ -25,7 +25,6 @@ #include #include #include -#include #include #include diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 1c75646f96..471a431029 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -26,13 +26,13 @@ #include #include +#include #include #include #include #include #include #include -#include #include "scsi_priv.h" #include "scsi_logging.h" @@ -1671,8 +1671,6 @@ scsi_reset_provider(struct scsi_device *dev, int flag) scmd->cmd_len = 0; scmd->sc_data_direction = DMA_BIDIRECTIONAL; - scmd->sc_request = NULL; - scmd->sc_magic = SCSI_CMND_MAGIC; init_timer(&scmd->eh_timeout); @@ -1769,14 +1767,6 @@ int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, } EXPORT_SYMBOL(scsi_normalize_sense); -int scsi_request_normalize_sense(struct scsi_request *sreq, - struct scsi_sense_hdr *sshdr) -{ - return scsi_normalize_sense(sreq->sr_sense_buffer, - sizeof(sreq->sr_sense_buffer), sshdr); -} -EXPORT_SYMBOL(scsi_request_normalize_sense); - int scsi_command_normalize_sense(struct scsi_cmnd *cmd, struct scsi_sense_hdr *sshdr) { diff --git a/drivers/scsi/scsi_ioctl.c b/drivers/scsi/scsi_ioctl.c index a89aff61d3..a89c4115cf 100644 --- a/drivers/scsi/scsi_ioctl.c +++ b/drivers/scsi/scsi_ioctl.c @@ -15,11 +15,11 @@ #include #include +#include #include #include #include #include -#include #include #include diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index bdce9d1f5b..3302d8068c 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -19,12 +19,12 @@ #include #include +#include #include #include #include #include #include -#include #include "scsi_priv.h" #include "scsi_logging.h" @@ -83,7 +83,7 @@ static void scsi_unprep_request(struct request *req) struct scsi_cmnd *cmd = req->special; req->flags &= ~REQ_DONTPREP; - req->special = (req->flags & REQ_SPECIAL) ? cmd->sc_request : NULL; + req->special = NULL; scsi_put_command(cmd); } @@ -161,72 +161,6 @@ int scsi_queue_insert(struct scsi_cmnd *cmd, int reason) return 0; } -/* - * Function: scsi_do_req - * - * Purpose: Queue a SCSI request - * - * Arguments: sreq - command descriptor. - * cmnd - actual SCSI command to be performed. - * buffer - data buffer. - * bufflen - size of data buffer. - * done - completion function to be run. - * timeout - how long to let it run before timeout. - * retries - number of retries we allow. - * - * Lock status: No locks held upon entry. - * - * Returns: Nothing. - * - * Notes: This function is only used for queueing requests for things - * like ioctls and character device requests - this is because - * we essentially just inject a request into the queue for the - * device. - * - * In order to support the scsi_device_quiesce function, we - * now inject requests on the *head* of the device queue - * rather than the tail. - */ -void scsi_do_req(struct scsi_request *sreq, const void *cmnd, - void *buffer, unsigned bufflen, - void (*done)(struct scsi_cmnd *), - int timeout, int retries) -{ - /* - * If the upper level driver is reusing these things, then - * we should release the low-level block now. Another one will - * be allocated later when this request is getting queued. - */ - __scsi_release_request(sreq); - - /* - * Our own function scsi_done (which marks the host as not busy, - * disables the timeout counter, etc) will be called by us or by the - * scsi_hosts[host].queuecommand() function needs to also call - * the completion function for the high level driver. - */ - memcpy(sreq->sr_cmnd, cmnd, sizeof(sreq->sr_cmnd)); - sreq->sr_bufflen = bufflen; - sreq->sr_buffer = buffer; - sreq->sr_allowed = retries; - sreq->sr_done = done; - sreq->sr_timeout_per_command = timeout; - - if (sreq->sr_cmd_len == 0) - sreq->sr_cmd_len = COMMAND_SIZE(sreq->sr_cmnd[0]); - - /* - * head injection *required* here otherwise quiesce won't work - * - * Because users of this function are apt to reuse requests with no - * modification, we have to sanitise the request flags here - */ - sreq->sr_request->flags &= ~REQ_DONTPREP; - blk_insert_request(sreq->sr_device->request_queue, sreq->sr_request, - 1, sreq); -} -EXPORT_SYMBOL(scsi_do_req); - /** * scsi_execute - insert request and wait for the result * @sdev: scsi device @@ -1300,15 +1234,7 @@ static int scsi_prep_fn(struct request_queue *q, struct request *req) * at request->cmd, as this tells us the real story. */ if (req->flags & REQ_SPECIAL && req->special) { - struct scsi_request *sreq = req->special; - - if (sreq->sr_magic == SCSI_REQ_MAGIC) { - cmd = scsi_get_command(sreq->sr_device, GFP_ATOMIC); - if (unlikely(!cmd)) - goto defer; - scsi_init_cmd_from_req(cmd, sreq); - } else - cmd = req->special; + cmd = req->special; } else if (req->flags & (REQ_CMD | REQ_BLOCK_PC)) { if(unlikely(specials_only) && !(req->flags & REQ_SPECIAL)) { diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h index 27c48274e8..a1727a0e1b 100644 --- a/drivers/scsi/scsi_priv.h +++ b/drivers/scsi/scsi_priv.h @@ -8,16 +8,9 @@ struct request_queue; struct scsi_cmnd; struct scsi_device; struct scsi_host_template; -struct scsi_request; struct Scsi_Host; -/* - * Magic values for certain scsi structs. Shouldn't ever be used. - */ -#define SCSI_CMND_MAGIC 0xE25C23A5 -#define SCSI_REQ_MAGIC 0x75F6D354 - /* * Scsi Error Handler Flags */ @@ -34,9 +27,6 @@ extern void scsi_exit_hosts(void); extern int scsi_dispatch_cmd(struct scsi_cmnd *cmd); extern int scsi_setup_command_freelist(struct Scsi_Host *shost); extern void scsi_destroy_command_freelist(struct Scsi_Host *shost); -extern void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, - struct scsi_request *sreq); -extern void __scsi_release_request(struct scsi_request *sreq); extern void __scsi_done(struct scsi_cmnd *cmd); extern int scsi_retry_command(struct scsi_cmnd *cmd); #ifdef CONFIG_SCSI_LOGGING diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index fd97d07577..0f7e6f94d6 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -33,11 +33,11 @@ #include #include +#include #include #include #include #include -#include #include #include diff --git a/drivers/scsi/scsi_typedefs.h b/drivers/scsi/scsi_typedefs.h index 29f038b42f..2ed4c5cb70 100644 --- a/drivers/scsi/scsi_typedefs.h +++ b/drivers/scsi/scsi_typedefs.h @@ -1,3 +1,2 @@ typedef struct scsi_cmnd Scsi_Cmnd; -typedef struct scsi_request Scsi_Request; diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 7602b9b15a..b0caabec1b 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -9,7 +9,6 @@ struct request; struct scatterlist; struct scsi_device; -struct scsi_request; /* embedded in scsi_cmnd */ @@ -29,13 +28,8 @@ struct scsi_pointer { }; struct scsi_cmnd { - int sc_magic; - struct scsi_device *device; - struct scsi_request *sc_request; - struct list_head list; /* scsi_cmnd participates in queue lists */ - struct list_head eh_entry; /* entry for the host eh_cmd_q */ int eh_eflags; /* Used by error handlr */ void (*done) (struct scsi_cmnd *); /* Mid-level done function */ diff --git a/include/scsi/scsi_dbg.h b/include/scsi/scsi_dbg.h index 4d69dee66d..3bbbfbe8cb 100644 --- a/include/scsi/scsi_dbg.h +++ b/include/scsi/scsi_dbg.h @@ -2,14 +2,12 @@ #define _SCSI_SCSI_DBG_H struct scsi_cmnd; -struct scsi_request; struct scsi_sense_hdr; extern void scsi_print_command(struct scsi_cmnd *); extern void scsi_print_sense_hdr(const char *, struct scsi_sense_hdr *); extern void __scsi_print_command(unsigned char *); extern void scsi_print_sense(const char *, struct scsi_cmnd *); -extern void scsi_print_req_sense(const char *, struct scsi_request *); extern void __scsi_print_sense(const char *name, const unsigned char *sense_buffer, int sense_len); diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h index d160880b2a..c5c0f6762a 100644 --- a/include/scsi/scsi_eh.h +++ b/include/scsi/scsi_eh.h @@ -3,7 +3,6 @@ struct scsi_cmnd; struct scsi_device; -struct scsi_request; struct Scsi_Host; /* @@ -43,8 +42,6 @@ extern void scsi_report_device_reset(struct Scsi_Host *, int, int); extern int scsi_block_when_processing_errors(struct scsi_device *); extern int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, struct scsi_sense_hdr *sshdr); -extern int scsi_request_normalize_sense(struct scsi_request *sreq, - struct scsi_sense_hdr *sshdr); extern int scsi_command_normalize_sense(struct scsi_cmnd *cmd, struct scsi_sense_hdr *sshdr); diff --git a/include/scsi/scsi_request.h b/include/scsi/scsi_request.h deleted file mode 100644 index 98d69fdb85..0000000000 --- a/include/scsi/scsi_request.h +++ /dev/null @@ -1,54 +0,0 @@ -#ifndef _SCSI_SCSI_REQUEST_H -#define _SCSI_SCSI_REQUEST_H - -#include - -struct request; -struct scsi_cmnd; -struct scsi_device; -struct Scsi_Host; - - -/* - * This is essentially a slimmed down version of Scsi_Cmnd. The point of - * having this is that requests that are injected into the queue as result - * of things like ioctls and character devices shouldn't be using a - * Scsi_Cmnd until such a time that the command is actually at the head - * of the queue and being sent to the driver. - */ -struct scsi_request { - int sr_magic; - int sr_result; /* Status code from lower level driver */ - unsigned char sr_sense_buffer[SCSI_SENSE_BUFFERSIZE]; /* obtained by REQUEST SENSE - * when CHECK CONDITION is - * received on original command - * (auto-sense) */ - - struct Scsi_Host *sr_host; - struct scsi_device *sr_device; - struct scsi_cmnd *sr_command; - struct request *sr_request; /* A copy of the command we are - working on */ - unsigned sr_bufflen; /* Size of data buffer */ - void *sr_buffer; /* Data buffer */ - int sr_allowed; - enum dma_data_direction sr_data_direction; - unsigned char sr_cmd_len; - unsigned char sr_cmnd[MAX_COMMAND_SIZE]; - void (*sr_done) (struct scsi_cmnd *); /* Mid-level done function */ - int sr_timeout_per_command; - unsigned short sr_use_sg; /* Number of pieces of scatter-gather */ - unsigned short sr_sglist_len; /* size of malloc'd scatter-gather list */ - unsigned sr_underflow; /* Return error if less than - this amount is transferred */ - void *upper_private_data; /* reserved for owner (usually upper - level driver) of this request */ -}; - -extern struct scsi_request *scsi_allocate_request(struct scsi_device *, gfp_t); -extern void scsi_release_request(struct scsi_request *); -extern void scsi_do_req(struct scsi_request *, const void *cmnd, - void *buffer, unsigned bufflen, - void (*done) (struct scsi_cmnd *), - int timeout, int retries); -#endif /* _SCSI_SCSI_REQUEST_H */ diff --git a/include/scsi/sg_request.h b/include/scsi/sg_request.h deleted file mode 100644 index 57ff525bdd..0000000000 --- a/include/scsi/sg_request.h +++ /dev/null @@ -1,26 +0,0 @@ -typedef struct scsi_request Scsi_Request; - -static Scsi_Request *dummy_cmdp; /* only used for sizeof */ - -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 bufflen; /* Size of (aggregate) data buffer */ - unsigned b_malloc_len; /* actual len malloc'ed in buffer */ - void *buffer; /* Data buffer or scatter list (k_use_sg>0) */ - char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */ - unsigned char cmd_opcode; /* first byte of command */ -} Sg_scatter_hold; - -typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */ - Scsi_Request *my_cmdp; /* != 0 when request with lower levels */ - 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 */ - sg_io_hdr_t header; /* scsi command+info, see */ - unsigned char sense_b[sizeof (dummy_cmdp->sr_sense_buffer)]; - char res_used; /* 1 -> using reserve buffer, 0 -> not ... */ - char orphan; /* 1 -> drop on sight, 0 -> normal */ - char sg_io_owned; /* 1 -> packet belongs to SG_IO */ - volatile char done; /* 0->before bh, 1->before read, 2->read */ -} Sg_request;