/* * 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 * Version 2 and 3 extensions to driver: * Copyright (C) 1998 - 2005 Douglas Gilbert * * Modified 19-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support * * 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. * */ static int sg_version_num = 30534; /* 2 digits for each component */ #define SG_VERSION_STR "3.5.34" /* * 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). * */ #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/init.h> #include <linux/poll.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> #include <linux/scatterlist.h> #include <linux/blktrace_api.h> #include <linux/smp_lock.h> #include "scsi.h" #include <scsi/scsi_dbg.h> #include <scsi/scsi_host.h> #include <scsi/scsi_driver.h> #include <scsi/scsi_ioctl.h> #include <scsi/sg.h> #include "scsi_logging.h" #ifdef CONFIG_SCSI_PROC_FS #include <linux/proc_fs.h> static char *sg_version_date = "20061027"; static int sg_proc_init(void); static void sg_proc_cleanup(void); #endif #define SG_ALLOW_DIO_DEF 0 #define SG_ALLOW_DIO_CODE /* compile out by commenting this define */ #define SG_MAX_DEVS 32768 /* * Suppose you want to calculate the formula muldiv(x,m,d)=int(x * m / d) * Then when using 32 bit integers x * m may overflow during the calculation. * Replacing muldiv(x) by muldiv(x)=((x % d) * m) / d + int(x / d) * m * calculates the same, but prevents the overflow when both m and d * are "small" numbers (like HZ and USER_HZ). * Of course an overflow is inavoidable if the result of muldiv doesn't fit * in 32 bits. */ #define MULDIV(X,MUL,DIV) ((((X % DIV) * MUL) / DIV) + ((X / DIV) * MUL)) #define SG_DEFAULT_TIMEOUT MULDIV(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ) int sg_big_buff = SG_DEF_RESERVED_SIZE; /* N.B. This variable is readable and writeable via /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer of this size (or less if there is not enough memory) will be reserved for use by this file descriptor. [Deprecated usage: this variable is also readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into the kernel (i.e. it is not a module).] */ static int def_reserved_size = -1; /* picks up init parameter */ static int sg_allow_dio = SG_ALLOW_DIO_DEF; static int scatter_elem_sz = SG_SCATTER_SZ; static int scatter_elem_sz_prev = SG_SCATTER_SZ; #define SG_SECTOR_SZ 512 #define SG_SECTOR_MSK (SG_SECTOR_SZ - 1) static int sg_add(struct device *, struct class_interface *); static void sg_remove(struct device *, struct class_interface *); 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 = { .add_dev = sg_add, .remove_dev = sg_remove, }; typedef struct sg_scatter_hold { /* holding area for scsi scatter gather info */ unsigned short k_use_sg; /* Count of kernel scatter-gather pieces */ 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 */ char dio_in_use; /* 0->indirect IO (or mmap), 1->dio */ unsigned char cmd_opcode; /* first byte of command */ } Sg_scatter_hold; struct sg_device; /* forward declarations */ struct sg_fd; typedef struct sg_request { /* SG_MAX_QUEUE requests outstanding per file */ 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 <scsi/sg.h> */ unsigned char sense_b[SCSI_SENSE_BUFFERSIZE]; 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; 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 */ rwlock_t rq_list_lock; /* protect access to list in req_arr */ int timeout; /* defaults to SG_DEFAULT_TIMEOUT */ int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */ 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 */ volatile char closed; /* 1 -> fd closed but request(s) outstanding */ char cmd_q; /* 1 -> allow command queuing, 0 -> don't */ char next_cmd_len; /* 0 -> automatic (def), >0 -> use on next write() */ char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */ char mmap_called; /* 0 -> mmap() never called on this fd */ } Sg_fd; 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 */ char sgdebug; /* 0->off, 1->sense, 9->dump dev, 10-> all devs */ struct gendisk *disk; struct cdev * cdev; /* char_dev [sysfs: /sys/cdev/major/sg<n>] */ } Sg_device; static int sg_fasync(int fd, struct file *filp, int mode); /* tasklet or soft irq callback */ static void sg_cmd_done(void *data, char *sense, int result, int resid); static int sg_start_req(Sg_request * srp); static void sg_finish_rem_req(Sg_request * srp); static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size); static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize); static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp); static ssize_t sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, size_t count, int blocking, int read_only, Sg_request **o_srp); static int sg_common_write(Sg_fd * sfp, Sg_request * srp, unsigned char *cmnd, int timeout, int blocking); static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind, int wr_xf, int *countp, unsigned char __user **up); static int sg_write_xfer(Sg_request * srp); static int sg_read_xfer(Sg_request * srp); static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer); static void sg_remove_scat(Sg_scatter_hold * schp); 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 struct page *sg_page_malloc(int rqSz, int lowDma, int *retSzp); static void sg_page_free(struct page *page, int size); static Sg_fd *sg_add_sfp(Sg_device * sdp, int dev); 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); static Sg_request *sg_add_request(Sg_fd * sfp); static int sg_remove_request(Sg_fd * sfp, Sg_request * srp); static int sg_res_in_use(Sg_fd * sfp); static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len); static Sg_device *sg_get_dev(int dev); #ifdef CONFIG_SCSI_PROC_FS static int sg_last_dev(void); #endif #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) #define SZ_SG_REQ_INFO sizeof(sg_req_info_t) static int sg_allow_access(struct file *filp, unsigned char *cmd) { struct sg_fd *sfp = (struct sg_fd *)filp->private_data; struct request_queue *q = sfp->parentdp->device->request_queue; if (sfp->parentdp->device->type == TYPE_SCANNER) return 0; return blk_verify_command(&q->cmd_filter, cmd, filp->f_mode & FMODE_WRITE); } static int sg_open(struct inode *inode, struct file *filp) { int dev = iminor(inode); int flags = filp->f_flags; struct request_queue *q; Sg_device *sdp; Sg_fd *sfp; int res; int retval; lock_kernel(); nonseekable_open(inode, filp); SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags)); sdp = sg_get_dev(dev); if ((!sdp) || (!sdp->device)) { unlock_kernel(); return -ENXIO; } if (sdp->detached) { unlock_kernel(); return -ENODEV; } /* 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) { unlock_kernel(); return retval; } if (!((flags & O_NONBLOCK) || scsi_block_when_processing_errors(sdp->device))) { retval = -ENXIO; /* we are in error recovery for this device */ goto error_out; } if (flags & O_EXCL) { if (O_RDONLY == (flags & O_ACCMODE)) { retval = -EPERM; /* Can't lock it with read only access */ goto error_out; } if (sdp->headfp && (flags & O_NONBLOCK)) { retval = -EBUSY; goto error_out; } res = 0; __wait_event_interruptible(sdp->o_excl_wait, ((sdp->headfp || sdp->exclude) ? 0 : (sdp->exclude = 1)), res); if (res) { retval = res; /* -ERESTARTSYS because signal hit process */ goto error_out; } } else if (sdp->exclude) { /* some other fd has an exclusive lock on dev */ if (flags & O_NONBLOCK) { retval = -EBUSY; goto error_out; } res = 0; __wait_event_interruptible(sdp->o_excl_wait, (!sdp->exclude), res); if (res) { retval = res; /* -ERESTARTSYS because signal hit process */ goto error_out; } } if (sdp->detached) { retval = -ENODEV; goto error_out; } if (!sdp->headfp) { /* no existing opens on this device */ sdp->sgdebug = 0; q = sdp->device->request_queue; sdp->sg_tablesize = min(q->max_hw_segments, q->max_phys_segments); } 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; } unlock_kernel(); return 0; error_out: scsi_device_put(sdp->device); unlock_kernel(); return retval; } /* 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: %s\n", sdp->disk->disk_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) { scsi_device_put(sdp->device); } sdp->exclude = 0; wake_up_interruptible(&sdp->o_excl_wait); } return 0; } static ssize_t sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) { Sg_device *sdp; Sg_fd *sfp; Sg_request *srp; int req_pack_id = -1; sg_io_hdr_t *hp; struct sg_header *old_hdr = NULL; int retval = 0; 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)); if (!access_ok(VERIFY_WRITE, buf, count)) return -EFAULT; if (sfp->force_packid && (count >= SZ_SG_HEADER)) { old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); if (!old_hdr) return -ENOMEM; if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) { retval = -EFAULT; goto free_old_hdr; } if (old_hdr->reply_len < 0) { if (count >= SZ_SG_IO_HDR) { sg_io_hdr_t *new_hdr; new_hdr = kmalloc(SZ_SG_IO_HDR, GFP_KERNEL); if (!new_hdr) { retval = -ENOMEM; goto free_old_hdr; } retval =__copy_from_user (new_hdr, buf, SZ_SG_IO_HDR); req_pack_id = new_hdr->pack_id; kfree(new_hdr); if (retval) { retval = -EFAULT; goto free_old_hdr; } } } else req_pack_id = old_hdr->pack_id; } srp = sg_get_rq_mark(sfp, req_pack_id); if (!srp) { /* now wait on packet to arrive */ if (sdp->detached) { retval = -ENODEV; goto free_old_hdr; } if (filp->f_flags & O_NONBLOCK) { retval = -EAGAIN; goto free_old_hdr; } while (1) { retval = 0; /* following macro beats race condition */ __wait_event_interruptible(sfp->read_wait, (sdp->detached || (srp = sg_get_rq_mark(sfp, req_pack_id))), retval); if (sdp->detached) { retval = -ENODEV; goto free_old_hdr; } if (0 == retval) break; /* -ERESTARTSYS as signal hit process */ goto free_old_hdr; } } if (srp->header.interface_id != '\0') { retval = sg_new_read(sfp, buf, count, srp); goto free_old_hdr; } hp = &srp->header; if (old_hdr == NULL) { old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); if (! old_hdr) { retval = -ENOMEM; goto free_old_hdr; } } memset(old_hdr, 0, SZ_SG_HEADER); old_hdr->reply_len = (int) hp->timeout; old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */ old_hdr->pack_id = hp->pack_id; old_hdr->twelve_byte = ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0; old_hdr->target_status = hp->masked_status; old_hdr->host_status = hp->host_status; old_hdr->driver_status = hp->driver_status; if ((CHECK_CONDITION & hp->masked_status) || (DRIVER_SENSE & hp->driver_status)) memcpy(old_hdr->sense_buffer, srp->sense_b, sizeof (old_hdr->sense_buffer)); switch (hp->host_status) { /* 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: old_hdr->result = 0; break; case DID_NO_CONNECT: case DID_BUS_BUSY: case DID_TIME_OUT: old_hdr->result = EBUSY; break; case DID_BAD_TARGET: case DID_ABORT: case DID_PARITY: case DID_RESET: case DID_BAD_INTR: old_hdr->result = EIO; break; case DID_ERROR: old_hdr->result = (srp->sense_b[0] == 0 && hp->masked_status == GOOD) ? 0 : EIO; break; default: old_hdr->result = EIO; break; } /* Now copy the result back to the user buffer. */ if (count >= SZ_SG_HEADER) { if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { retval = -EFAULT; goto free_old_hdr; } buf += SZ_SG_HEADER; if (count > old_hdr->reply_len) count = old_hdr->reply_len; if (count > SZ_SG_HEADER) { if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) { retval = -EFAULT; goto free_old_hdr; } } } else count = (old_hdr->result == 0) ? 0 : -EIO; sg_finish_rem_req(srp); retval = count; free_old_hdr: kfree(old_hdr); return retval; } static ssize_t sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp) { sg_io_hdr_t *hp = &srp->header; int err = 0; int len; if (count < SZ_SG_IO_HDR) { err = -EINVAL; goto err_out; } hp->sb_len_wr = 0; if ((hp->mx_sb_len > 0) && hp->sbp) { if ((CHECK_CONDITION & hp->masked_status) || (DRIVER_SENSE & hp->driver_status)) { int sb_len = SCSI_SENSE_BUFFERSIZE; sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len; len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */ len = (len > sb_len) ? sb_len : len; if (copy_to_user(hp->sbp, srp->sense_b, len)) { err = -EFAULT; goto err_out; } hp->sb_len_wr = len; } } if (hp->masked_status || hp->host_status || hp->driver_status) hp->info |= SG_INFO_CHECK; if (copy_to_user(buf, hp, SZ_SG_IO_HDR)) { err = -EFAULT; goto err_out; } err = sg_read_xfer(srp); err_out: sg_finish_rem_req(srp); return (0 == err) ? count : err; } static ssize_t sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos) { int mxsize, cmd_size, k; int input_size, blocking; unsigned char opcode; Sg_device *sdp; Sg_fd *sfp; Sg_request *srp; struct sg_header old_hdr; sg_io_hdr_t *hp; unsigned char cmnd[MAX_COMMAND_SIZE]; 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)); if (sdp->detached) return -ENODEV; if (!((filp->f_flags & O_NONBLOCK) || scsi_block_when_processing_errors(sdp->device))) return -ENXIO; if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; /* protects following copy_from_user()s + get_user()s */ if (count < SZ_SG_HEADER) return -EIO; if (__copy_from_user(&old_hdr, buf, SZ_SG_HEADER)) return -EFAULT; blocking = !(filp->f_flags & O_NONBLOCK); if (old_hdr.reply_len < 0) return sg_new_write(sfp, filp, buf, count, blocking, 0, NULL); if (count < (SZ_SG_HEADER + 6)) return -EIO; /* The minimum scsi command length is 6 bytes. */ if (!(srp = sg_add_request(sfp))) { SCSI_LOG_TIMEOUT(1, printk("sg_write: queue full\n")); return -EDOM; } buf += SZ_SG_HEADER; __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; sg_remove_request(sfp, srp); return -EIO; } 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) && old_hdr.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 > old_hdr.reply_len) ? input_size : old_hdr.reply_len; mxsize -= SZ_SG_HEADER; input_size -= SZ_SG_HEADER; if (input_size < 0) { sg_remove_request(sfp, srp); return -EIO; /* User did not pass enough bytes for this command. */ } hp = &srp->header; hp->interface_id = '\0'; /* indicator of old interface tunnelled */ hp->cmd_len = (unsigned char) cmd_size; hp->iovec_count = 0; hp->mx_sb_len = 0; if (input_size > 0) hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ? SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV; else hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE; hp->dxfer_len = mxsize; hp->dxferp = (char __user *)buf + cmd_size; hp->sbp = NULL; hp->timeout = old_hdr.reply_len; /* structure abuse ... */ hp->flags = input_size; /* structure abuse ... */ hp->pack_id = old_hdr.pack_id; hp->usr_ptr = NULL; if (__copy_from_user(cmnd, buf, cmd_size)) return -EFAULT; /* * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV, * but is is possible that the app intended SG_DXFER_TO_DEV, because there * is a non-zero input_size, so emit a warning. */ if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) { static char cmd[TASK_COMM_LEN]; if (strcmp(current->comm, cmd) && printk_ratelimit()) { printk(KERN_WARNING "sg_write: data in/out %d/%d bytes for SCSI command 0x%x--" "guessing data in;\n" KERN_WARNING " " "program %s not setting count and/or reply_len properly\n", old_hdr.reply_len - (int)SZ_SG_HEADER, input_size, (unsigned int) cmnd[0], current->comm); strcpy(cmd, current->comm); } } k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking); return (k < 0) ? k : count; } static ssize_t sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf, size_t count, int blocking, int read_only, Sg_request **o_srp) { int k; Sg_request *srp; sg_io_hdr_t *hp; unsigned char cmnd[MAX_COMMAND_SIZE]; int timeout; unsigned long ul_timeout; if (count < SZ_SG_IO_HDR) return -EINVAL; if (!access_ok(VERIFY_READ, buf, count)) return -EFAULT; /* protects following copy_from_user()s + get_user()s */ sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */ if (!(srp = sg_add_request(sfp))) { SCSI_LOG_TIMEOUT(1, printk("sg_new_write: queue full\n")); return -EDOM; } hp = &srp->header; if (__copy_from_user(hp, buf, SZ_SG_IO_HDR)) { sg_remove_request(sfp, srp); return -EFAULT; } if (hp->interface_id != 'S') { sg_remove_request(sfp, srp); return -ENOSYS; } if (hp->flags & SG_FLAG_MMAP_IO) { if (hp->dxfer_len > sfp->reserve.bufflen) { sg_remove_request(sfp, srp); return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */ } if (hp->flags & SG_FLAG_DIRECT_IO) { sg_remove_request(sfp, srp); return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */ } if (sg_res_in_use(sfp)) { sg_remove_request(sfp, srp); return -EBUSY; /* reserve buffer already being used */ } } ul_timeout = msecs_to_jiffies(srp->header.timeout); timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX; if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) { sg_remove_request(sfp, srp); return -EMSGSIZE; } if (!access_ok(VERIFY_READ, hp->cmdp, hp->cmd_len)) { sg_remove_request(sfp, srp); return -EFAULT; /* protects following copy_from_user()s + get_user()s */ } if (__copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) { sg_remove_request(sfp, srp); return -EFAULT; } if (read_only && sg_allow_access(file, cmnd)) { sg_remove_request(sfp, srp); return -EPERM; } k = sg_common_write(sfp, srp, cmnd, timeout, blocking); if (k < 0) return k; if (o_srp) *o_srp = srp; return count; } static int sg_common_write(Sg_fd * sfp, Sg_request * srp, unsigned char *cmnd, int timeout, int blocking) { int k, data_dir; Sg_device *sdp = sfp->parentdp; sg_io_hdr_t *hp = &srp->header; srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */ hp->status = 0; hp->masked_status = 0; hp->msg_status = 0; hp->info = 0; hp->host_status = 0; hp->driver_status = 0; hp->resid = 0; SCSI_LOG_TIMEOUT(4, printk("sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) cmnd[0], (int) hp->cmd_len)); if ((k = sg_start_req(srp))) { SCSI_LOG_TIMEOUT(1, printk("sg_common_write: start_req err=%d\n", k)); sg_finish_rem_req(srp); return k; /* probably out of space --> ENOMEM */ } if ((k = sg_write_xfer(srp))) { SCSI_LOG_TIMEOUT(1, printk("sg_common_write: write_xfer, bad address\n")); sg_finish_rem_req(srp); return k; } if (sdp->detached) { sg_finish_rem_req(srp); return -ENODEV; } switch (hp->dxfer_direction) { case SG_DXFER_TO_FROM_DEV: case SG_DXFER_FROM_DEV: data_dir = DMA_FROM_DEVICE; break; case SG_DXFER_TO_DEV: data_dir = DMA_TO_DEVICE; break; case SG_DXFER_UNKNOWN: data_dir = DMA_BIDIRECTIONAL; break; default: data_dir = DMA_NONE; break; } hp->duration = jiffies_to_msecs(jiffies); /* Now send everything of to mid-level. The next time we hear about this packet is when sg_cmd_done() is called (i.e. a callback). */ if (scsi_execute_async(sdp->device, cmnd, hp->cmd_len, data_dir, srp->data.buffer, hp->dxfer_len, srp->data.k_use_sg, timeout, SG_DEFAULT_RETRIES, srp, sg_cmd_done, GFP_ATOMIC)) { SCSI_LOG_TIMEOUT(1, printk("sg_common_write: scsi_execute_async failed\n")); /* * most likely out of mem, but could also be a bad map */ sg_finish_rem_req(srp); return -ENOMEM; } else return 0; } static int sg_srp_done(Sg_request *srp, Sg_fd *sfp) { unsigned long iflags; int done; read_lock_irqsave(&sfp->rq_list_lock, iflags); done = srp->done; read_unlock_irqrestore(&sfp->rq_list_lock, iflags); return done; } static int sg_ioctl(struct inode *inode, struct file *filp, unsigned int cmd_in, unsigned long arg) { void __user *p = (void __user *)arg; int __user *ip = p; int result, val, read_only; Sg_device *sdp; Sg_fd *sfp; Sg_request *srp; unsigned long iflags; 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)); read_only = (O_RDWR != (filp->f_flags & O_ACCMODE)); switch (cmd_in) { case SG_IO: { int blocking = 1; /* ignore O_NONBLOCK flag */ if (sdp->detached) return -ENODEV; if (!scsi_block_when_processing_errors(sdp->device)) return -ENXIO; if (!access_ok(VERIFY_WRITE, p, SZ_SG_IO_HDR)) return -EFAULT; result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR, blocking, read_only, &srp); if (result < 0) return result; srp->sg_io_owned = 1; while (1) { result = 0; /* following macro to beat race condition */ __wait_event_interruptible(sfp->read_wait, (sdp->detached || sfp->closed || sg_srp_done(srp, sfp)), result); if (sdp->detached) return -ENODEV; if (sfp->closed) return 0; /* request packet dropped already */ if (0 == result) break; srp->orphan = 1; return result; /* -ERESTARTSYS because signal hit process */ } write_lock_irqsave(&sfp->rq_list_lock, iflags); srp->done = 2; write_unlock_irqrestore(&sfp->rq_list_lock, iflags); result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp); return (result < 0) ? result : 0; } case SG_SET_TIMEOUT: result = get_user(val, ip); if (result) return result; if (val < 0) return -EIO; if (val >= MULDIV (INT_MAX, USER_HZ, HZ)) val = MULDIV (INT_MAX, USER_HZ, HZ); sfp->timeout_user = val; sfp->timeout = MULDIV (val, HZ, USER_HZ); return 0; case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */ /* strange ..., for backward compatibility */ return sfp->timeout_user; case SG_SET_FORCE_LOW_DMA: result = get_user(val, ip); 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 { if (sdp->detached) return -ENODEV; sfp->low_dma = sdp->device->host->unchecked_isa_dma; } return 0; case SG_GET_LOW_DMA: return put_user((int) sfp->low_dma, ip); case SG_GET_SCSI_ID: if (!access_ok(VERIFY_WRITE, p, sizeof (sg_scsi_id_t))) return -EFAULT; else { sg_scsi_id_t __user *sg_idp = p; if (sdp->detached) return -ENODEV; __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((short) sdp->device->host->cmd_per_lun, &sg_idp->h_cmd_per_lun); __put_user((short) sdp->device->queue_depth, &sg_idp->d_queue_depth); __put_user(0, &sg_idp->unused[0]); __put_user(0, &sg_idp->unused[1]); return 0; } case SG_SET_FORCE_PACK_ID: result = get_user(val, ip); if (result) return result; sfp->force_packid = val ? 1 : 0; return 0; case SG_GET_PACK_ID: if (!access_ok(VERIFY_WRITE, ip, sizeof (int))) return -EFAULT; read_lock_irqsave(&sfp->rq_list_lock, iflags); for (srp = sfp->headrp; srp; srp = srp->nextrp) { if ((1 == srp->done) && (!srp->sg_io_owned)) { read_unlock_irqrestore(&sfp->rq_list_lock, iflags); __put_user(srp->header.pack_id, ip); return 0; } } read_unlock_irqrestore(&sfp->rq_list_lock, iflags); __put_user(-1, ip); return 0; case SG_GET_NUM_WAITING: read_lock_irqsave(&sfp->rq_list_lock, iflags); for (val = 0, srp = sfp->headrp; srp; srp = srp->nextrp) { if ((1 == srp->done) && (!srp->sg_io_owned)) ++val; } read_unlock_irqrestore(&sfp->rq_list_lock, iflags); return put_user(val, ip); case SG_GET_SG_TABLESIZE: return put_user(sdp->sg_tablesize, ip); case SG_SET_RESERVED_SIZE: result = get_user(val, ip); if (result) return result; if (val < 0) return -EINVAL; val = min_t(int, val, sdp->device->request_queue->max_sectors * 512); if (val != sfp->reserve.bufflen) { if (sg_res_in_use(sfp) || sfp->mmap_called) return -EBUSY; sg_remove_scat(&sfp->reserve); sg_build_reserve(sfp, val); } return 0; case SG_GET_RESERVED_SIZE: val = min_t(int, sfp->reserve.bufflen, sdp->device->request_queue->max_sectors * 512); return put_user(val, ip); case SG_SET_COMMAND_Q: result = get_user(val, ip); if (result) return result; sfp->cmd_q = val ? 1 : 0; return 0; case SG_GET_COMMAND_Q: return put_user((int) sfp->cmd_q, ip); case SG_SET_KEEP_ORPHAN: result = get_user(val, ip); if (result) return result; sfp->keep_orphan = val; return 0; case SG_GET_KEEP_ORPHAN: return put_user((int) sfp->keep_orphan, ip); case SG_NEXT_CMD_LEN: result = get_user(val, ip); 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, ip); case SG_GET_ACCESS_COUNT: /* faked - we don't have a real access count anymore */ val = (sdp->device ? 1 : 0); return put_user(val, ip); case SG_GET_REQUEST_TABLE: if (!access_ok(VERIFY_WRITE, p, SZ_SG_REQ_INFO * SG_MAX_QUEUE)) return -EFAULT; else { sg_req_info_t *rinfo; unsigned int ms; rinfo = kmalloc(SZ_SG_REQ_INFO * SG_MAX_QUEUE, GFP_KERNEL); if (!rinfo) return -ENOMEM; read_lock_irqsave(&sfp->rq_list_lock, iflags); for (srp = sfp->headrp, val = 0; val < SG_MAX_QUEUE; ++val, srp = srp ? srp->nextrp : srp) { memset(&rinfo[val], 0, SZ_SG_REQ_INFO); if (srp) { rinfo[val].req_state = srp->done + 1; rinfo[val].problem = srp->header.masked_status & srp->header.host_status & srp->header.driver_status; if (srp->done) rinfo[val].duration = srp->header.duration; else { ms = jiffies_to_msecs(jiffies); rinfo[val].duration = (ms > srp->header.duration) ? (ms - srp->header.duration) : 0; } rinfo[val].orphan = srp->orphan; rinfo[val].sg_io_owned = srp->sg_io_owned; rinfo[val].pack_id = srp->header.pack_id; rinfo[val].usr_ptr = srp->header.usr_ptr; } } read_unlock_irqrestore(&sfp->rq_list_lock, iflags); result = __copy_to_user(p, rinfo, SZ_SG_REQ_INFO * SG_MAX_QUEUE); result = result ? -EFAULT : 0; kfree(rinfo); return result; } case SG_EMULATED_HOST: if (sdp->detached) return -ENODEV; return put_user(sdp->device->host->hostt->emulated, ip); case SG_SCSI_RESET: if (sdp->detached) return -ENODEV; if (filp->f_flags & O_NONBLOCK) { if (scsi_host_in_recovery(sdp->device->host)) return -EBUSY; } else if (!scsi_block_when_processing_errors(sdp->device)) return -EBUSY; result = get_user(val, ip); if (result) return result; if (SG_SCSI_RESET_NOTHING == val) return 0; switch (val) { case SG_SCSI_RESET_DEVICE: val = SCSI_TRY_RESET_DEVICE; break; case SG_SCSI_RESET_TARGET: val = SCSI_TRY_RESET_TARGET; break; case SG_SCSI_RESET_BUS: val = SCSI_TRY_RESET_BUS; break; case SG_SCSI_RESET_HOST: val = SCSI_TRY_RESET_HOST; break; default: return -EINVAL; } if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; return (scsi_reset_provider(sdp->device, val) == SUCCESS) ? 0 : -EIO; case SCSI_IOCTL_SEND_COMMAND: if (sdp->detached) return -ENODEV; if (read_only) { unsigned char opcode = WRITE_6; Scsi_Ioctl_Command __user *siocp = p; if (copy_from_user(&opcode, siocp->data, 1)) return -EFAULT; if (sg_allow_access(filp, &opcode)) return -EPERM; } return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p); case SG_SET_DEBUG: result = get_user(val, ip); if (result) return result; sdp->sgdebug = (char) val; return 0; case SCSI_IOCTL_GET_IDLUN: case SCSI_IOCTL_GET_BUS_NUMBER: case SCSI_IOCTL_PROBE_HOST: case SG_GET_TRANSFORM: if (sdp->detached) return -ENODEV; return scsi_ioctl(sdp->device, cmd_in, p); case BLKSECTGET: return put_user(sdp->device->request_queue->max_sectors * 512, ip); case BLKTRACESETUP: return blk_trace_setup(sdp->device->request_queue, sdp->disk->disk_name, sdp->device->sdev_gendev.devt, (char *)arg); case BLKTRACESTART: return blk_trace_startstop(sdp->device->request_queue, 1); case BLKTRACESTOP: return blk_trace_startstop(sdp->device->request_queue, 0); case BLKTRACETEARDOWN: return blk_trace_remove(sdp->device->request_queue); default: if (read_only) return -EPERM; /* don't know so take safe approach */ return scsi_ioctl(sdp->device, cmd_in, p); } } #ifdef CONFIG_COMPAT static long sg_compat_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg) { Sg_device *sdp; Sg_fd *sfp; struct scsi_device *sdev; if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp))) return -ENXIO; sdev = sdp->device; if (sdev->host->hostt->compat_ioctl) { int ret; ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg); return ret; } return -ENOIOCTLCMD; } #endif 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; unsigned long iflags; if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)) || sfp->closed) return POLLERR; poll_wait(filp, &sfp->read_wait, wait); read_lock_irqsave(&sfp->rq_list_lock, iflags); for (srp = sfp->headrp; srp; srp = srp->nextrp) { /* if any read waiting, flag it */ if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned)) res = POLLIN | POLLRDNORM; ++count; } read_unlock_irqrestore(&sfp->rq_list_lock, iflags); if (sdp->detached) res |= POLLHUP; else if (!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: %s, res=0x%x\n", sdp->disk->disk_name, (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: %s, mode=%d\n", sdp->disk->disk_name, mode)); retval = fasync_helper(fd, filp, mode, &sfp->async_qp); return (retval < 0) ? retval : 0; } static int sg_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { Sg_fd *sfp; unsigned long offset, len, sa; Sg_scatter_hold *rsv_schp; struct scatterlist *sg; int k; if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data))) return VM_FAULT_SIGBUS; rsv_schp = &sfp->reserve; offset = vmf->pgoff << PAGE_SHIFT; if (offset >= rsv_schp->bufflen) return VM_FAULT_SIGBUS; SCSI_LOG_TIMEOUT(3, printk("sg_vma_fault: offset=%lu, scatg=%d\n", offset, rsv_schp->k_use_sg)); sg = rsv_schp->buffer; sa = vma->vm_start; for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end); ++k, sg = sg_next(sg)) { len = vma->vm_end - sa; len = (len < sg->length) ? len : sg->length; if (offset < len) { struct page *page; page = virt_to_page(page_address(sg_page(sg)) + offset); get_page(page); /* increment page count */ vmf->page = page; return 0; /* success */ } sa += len; offset -= len; } return VM_FAULT_SIGBUS; } static struct vm_operations_struct sg_mmap_vm_ops = { .fault = sg_vma_fault, }; static int sg_mmap(struct file *filp, struct vm_area_struct *vma) { Sg_fd *sfp; unsigned long req_sz, len, sa; Sg_scatter_hold *rsv_schp; int k; struct scatterlist *sg; if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data))) return -ENXIO; req_sz = vma->vm_end - vma->vm_start; SCSI_LOG_TIMEOUT(3, printk("sg_mmap starting, vm_start=%p, len=%d\n", (void *) vma->vm_start, (int) req_sz)); if (vma->vm_pgoff) return -EINVAL; /* want no offset */ rsv_schp = &sfp->reserve; if (req_sz > rsv_schp->bufflen) return -ENOMEM; /* cannot map more than reserved buffer */ sa = vma->vm_start; sg = rsv_schp->buffer; for (k = 0; (k < rsv_schp->k_use_sg) && (sa < vma->vm_end); ++k, sg = sg_next(sg)) { len = vma->vm_end - sa; len = (len < sg->length) ? len : sg->length; sa += len; } sfp->mmap_called = 1; vma->vm_flags |= VM_RESERVED; vma->vm_private_data = sfp; vma->vm_ops = &sg_mmap_vm_ops; return 0; } /* This function is a "bottom half" handler that is called by the * mid level when a command is completed (or has failed). */ static void sg_cmd_done(void *data, char *sense, int result, int resid) { Sg_request *srp = data; Sg_device *sdp = NULL; Sg_fd *sfp; unsigned long iflags; unsigned int ms; if (NULL == srp) { printk(KERN_ERR "sg_cmd_done: NULL request\n"); return; } sfp = srp->parentfp; if (sfp) sdp = sfp->parentdp; if ((NULL == sdp) || sdp->detached) { printk(KERN_INFO "sg_cmd_done: device detached\n"); return; } SCSI_LOG_TIMEOUT(4, printk("sg_cmd_done: %s, pack_id=%d, res=0x%x\n", sdp->disk->disk_name, srp->header.pack_id, result)); srp->header.resid = resid; ms = jiffies_to_msecs(jiffies); srp->header.duration = (ms > srp->header.duration) ? (ms - srp->header.duration) : 0; if (0 != result) { struct scsi_sense_hdr sshdr; memcpy(srp->sense_b, sense, sizeof (srp->sense_b)); srp->header.status = 0xff & result; srp->header.masked_status = status_byte(result); srp->header.msg_status = msg_byte(result); srp->header.host_status = host_byte(result); srp->header.driver_status = driver_byte(result); if ((sdp->sgdebug > 0) && ((CHECK_CONDITION == srp->header.masked_status) || (COMMAND_TERMINATED == srp->header.masked_status))) __scsi_print_sense("sg_cmd_done", sense, SCSI_SENSE_BUFFERSIZE); /* Following if statement is a patch supplied by Eric Youngdale */ if (driver_byte(result) != 0 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr) && !scsi_sense_is_deferred(&sshdr) && sshdr.sense_key == UNIT_ATTENTION && sdp->device->removable) { /* Detected possible disc change. Set the bit - this */ /* may be used if there are filesystems using this device */ sdp->device->changed = 1; } } /* Rely on write phase to clean out srp status values, so no "else" */ if (sfp->closed) { /* whoops this fd already released, cleanup */ SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, freeing ...\n")); sg_finish_rem_req(srp); srp = NULL; if (NULL == sfp->headrp) { SCSI_LOG_TIMEOUT(1, printk("sg_cmd_done: already closed, final cleanup\n")); if (0 == sg_remove_sfp(sdp, sfp)) { /* device still present */ scsi_device_put(sdp->device); } sfp = NULL; } } else if (srp && srp->orphan) { if (sfp->keep_orphan) srp->sg_io_owned = 0; else { sg_finish_rem_req(srp); srp = NULL; } } if (sfp && srp) { /* Now wake up any sg_read() that is waiting for this packet. */ kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN); write_lock_irqsave(&sfp->rq_list_lock, iflags); srp->done = 1; wake_up_interruptible(&sfp->read_wait); write_unlock_irqrestore(&sfp->rq_list_lock, iflags); } } static struct file_operations sg_fops = { .owner = THIS_MODULE, .read = sg_read, .write = sg_write, .poll = sg_poll, .ioctl = sg_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = sg_compat_ioctl, #endif .open = sg_open, .mmap = sg_mmap, .release = sg_release, .fasync = sg_fasync, }; static struct class *sg_sysfs_class; static int sg_sysfs_valid = 0; 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; int error; u32 k; sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL); if (!sdp) { printk(KERN_WARNING "kmalloc Sg_device failure\n"); 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_index_lock, iflags); error = idr_get_new(&sg_index_idr, sdp, &k); write_unlock_irqrestore(&sg_index_lock, iflags); if (error) { printk(KERN_WARNING "idr allocation Sg_device failure: %d\n", error); goto out; } if (unlikely(k >= SG_MAX_DEVS)) goto overflow; SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k)); sprintf(disk->disk_name, "sg%d", k); disk->first_minor = k; sdp->disk = disk; 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; error = 0; out: if (error) { kfree(sdp); return ERR_PTR(error); } return sdp; overflow: sdev_printk(KERN_WARNING, scsidp, "Unable to attach sg device type=%d, minor " "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1); error = -ENODEV; goto out; } static int sg_add(struct device *cl_dev, struct class_interface *cl_intf) { struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); struct gendisk *disk; Sg_device *sdp = NULL; struct cdev * cdev = NULL; int error; unsigned long iflags; disk = alloc_disk(1); if (!disk) { printk(KERN_WARNING "alloc_disk failed\n"); return -ENOMEM; } disk->major = SCSI_GENERIC_MAJOR; error = -ENOMEM; cdev = cdev_alloc(); if (!cdev) { printk(KERN_WARNING "cdev_alloc failed\n"); goto out; } cdev->owner = THIS_MODULE; cdev->ops = &sg_fops; sdp = sg_alloc(disk, scsidp); if (IS_ERR(sdp)) { printk(KERN_WARNING "sg_alloc failed\n"); error = PTR_ERR(sdp); goto out; } error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1); if (error) goto cdev_add_err; sdp->cdev = cdev; if (sg_sysfs_valid) { struct device *sg_class_member; sg_class_member = device_create_drvdata(sg_sysfs_class, cl_dev->parent, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), sdp, "%s", disk->disk_name); if (IS_ERR(sg_class_member)) { printk(KERN_ERR "sg_add: " "device_create failed\n"); error = PTR_ERR(sg_class_member); goto cdev_add_err; } error = sysfs_create_link(&scsidp->sdev_gendev.kobj, &sg_class_member->kobj, "generic"); if (error) printk(KERN_ERR "sg_add: unable to make symlink " "'generic' back to sg%d\n", sdp->index); } else printk(KERN_WARNING "sg_add: sg_sys Invalid\n"); sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d type %d\n", sdp->index, scsidp->type); dev_set_drvdata(cl_dev, sdp); return 0; cdev_add_err: 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); if (cdev) cdev_del(cdev); return error; } static void sg_remove(struct device *cl_dev, struct class_interface *cl_intf) { struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); Sg_device *sdp = dev_get_drvdata(cl_dev); unsigned long iflags; Sg_fd *sfp; Sg_fd *tsfp; Sg_request *srp; Sg_request *tsrp; int delay; if (!sdp) return; delay = 0; 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); } 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); } } 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"); 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 */ } module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR); module_param_named(def_reserved_size, def_reserved_size, int, S_IRUGO | S_IWUSR); module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR); MODULE_AUTHOR("Douglas Gilbert"); MODULE_DESCRIPTION("SCSI generic (sg) driver"); MODULE_LICENSE("GPL"); MODULE_VERSION(SG_VERSION_STR); MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR); MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element " "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))"); MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd"); MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))"); static int __init init_sg(void) { int rc; if (scatter_elem_sz < PAGE_SIZE) { scatter_elem_sz = PAGE_SIZE; scatter_elem_sz_prev = scatter_elem_sz; } if (def_reserved_size >= 0) sg_big_buff = def_reserved_size; else def_reserved_size = sg_big_buff; rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS, "sg"); if (rc) return rc; sg_sysfs_class = class_create(THIS_MODULE, "scsi_generic"); if ( IS_ERR(sg_sysfs_class) ) { rc = PTR_ERR(sg_sysfs_class); goto err_out; } sg_sysfs_valid = 1; rc = scsi_register_interface(&sg_interface); if (0 == rc) { #ifdef CONFIG_SCSI_PROC_FS sg_proc_init(); #endif /* CONFIG_SCSI_PROC_FS */ return 0; } class_destroy(sg_sysfs_class); err_out: unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); return rc; } static void __exit exit_sg(void) { #ifdef CONFIG_SCSI_PROC_FS sg_proc_cleanup(); #endif /* CONFIG_SCSI_PROC_FS */ scsi_unregister_interface(&sg_interface); class_destroy(sg_sysfs_class); sg_sysfs_valid = 0; unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS); idr_destroy(&sg_index_idr); } static int sg_start_req(Sg_request * srp) { int res; Sg_fd *sfp = srp->parentfp; sg_io_hdr_t *hp = &srp->header; int dxfer_len = (int) hp->dxfer_len; int dxfer_dir = hp->dxfer_direction; Sg_scatter_hold *req_schp = &srp->data; Sg_scatter_hold *rsv_schp = &sfp->reserve; SCSI_LOG_TIMEOUT(4, printk("sg_start_req: dxfer_len=%d\n", dxfer_len)); if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE)) return 0; if (sg_allow_dio && (hp->flags & SG_FLAG_DIRECT_IO) && (dxfer_dir != SG_DXFER_UNKNOWN) && (0 == hp->iovec_count) && (!sfp->parentdp->device->host->unchecked_isa_dma)) { res = sg_build_direct(srp, sfp, dxfer_len); if (res <= 0) /* -ve -> error, 0 -> done, 1 -> try indirect */ return res; } if ((!sg_res_in_use(sfp)) && (dxfer_len <= rsv_schp->bufflen)) sg_link_reserve(sfp, srp, dxfer_len); else { res = sg_build_indirect(req_schp, sfp, dxfer_len); if (res) { sg_remove_scat(req_schp); return res; } } return 0; } static void sg_finish_rem_req(Sg_request * srp) { 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 (srp->res_used) sg_unlink_reserve(sfp, srp); else sg_remove_scat(req_schp); sg_remove_request(sfp, srp); } static int sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize) { int sg_bufflen = tablesize * sizeof(struct scatterlist); gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN; /* * TODO: test without low_dma, we should not need it since * the block layer will bounce the buffer for us * * XXX(hch): we shouldn't need GFP_DMA for the actual S/G list. */ if (sfp->low_dma) gfp_flags |= GFP_DMA; schp->buffer = kzalloc(sg_bufflen, gfp_flags); if (!schp->buffer) return -ENOMEM; sg_init_table(schp->buffer, tablesize); schp->sglist_len = sg_bufflen; return tablesize; /* number of scat_gath elements allocated */ } #ifdef SG_ALLOW_DIO_CODE /* vvvvvvvv following code borrowed from st driver's direct IO vvvvvvvvv */ /* TODO: hopefully we can use the generic block layer code */ /* Pin down user pages and put them into a scatter gather list. Returns <= 0 if - mapping of all pages not successful (i.e., either completely successful or fails) */ static int st_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages, unsigned long uaddr, size_t count, int rw) { unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT; unsigned long start = uaddr >> PAGE_SHIFT; const int nr_pages = end - start; int res, i, j; struct page **pages; /* User attempted Overflow! */ if ((uaddr + count) < uaddr) return -EINVAL; /* Too big */ if (nr_pages > max_pages) return -ENOMEM; /* Hmm? */ if (count == 0) return 0; if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_ATOMIC)) == NULL) return -ENOMEM; /* Try to fault in all of the necessary pages */ down_read(¤t->mm->mmap_sem); /* rw==READ means read from drive, write into memory area */ res = get_user_pages( current, current->mm, uaddr, nr_pages, rw == READ, 0, /* don't force */ pages, NULL); up_read(¤t->mm->mmap_sem); /* Errors and no page mapped should return here */ if (res < nr_pages) goto out_unmap; for (i=0; i < nr_pages; i++) { /* FIXME: flush superflous for rw==READ, * probably wrong function for rw==WRITE */ flush_dcache_page(pages[i]); /* ?? Is locking needed? I don't think so */ /* if (!trylock_page(pages[i])) goto out_unlock; */ } sg_set_page(sgl, pages[0], 0, uaddr & ~PAGE_MASK); if (nr_pages > 1) { sgl[0].length = PAGE_SIZE - sgl[0].offset; count -= sgl[0].length; for (i=1; i < nr_pages ; i++) sg_set_page(&sgl[i], pages[i], count < PAGE_SIZE ? count : PAGE_SIZE, 0); } else { sgl[0].length = count; } kfree(pages); return nr_pages; out_unmap: if (res > 0) { for (j=0; j < res; j++) page_cache_release(pages[j]); res = 0; } kfree(pages); return res; } /* And unmap them... */ static int st_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages, int dirtied) { int i; for (i=0; i < nr_pages; i++) { struct page *page = sg_page(&sgl[i]); if (dirtied) SetPageDirty(page); /* unlock_page(page); */ /* FIXME: cache flush missing for rw==READ * FIXME: call the correct reference counting function */ page_cache_release(page); } return 0; } /* ^^^^^^^^ above code borrowed from st driver's direct IO ^^^^^^^^^ */ #endif /* Returns: -ve -> error, 0 -> done, 1 -> try indirect */ static int sg_build_direct(Sg_request * srp, Sg_fd * sfp, int dxfer_len) { #ifdef SG_ALLOW_DIO_CODE sg_io_hdr_t *hp = &srp->header; Sg_scatter_hold *schp = &srp->data; int sg_tablesize = sfp->parentdp->sg_tablesize; int mx_sc_elems, res; struct scsi_device *sdev = sfp->parentdp->device; if (((unsigned long)hp->dxferp & queue_dma_alignment(sdev->request_queue)) != 0) return 1; mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); if (mx_sc_elems <= 0) { return 1; } res = st_map_user_pages(schp->buffer, mx_sc_elems, (unsigned long)hp->dxferp, dxfer_len, (SG_DXFER_TO_DEV == hp->dxfer_direction) ? 1 : 0); if (res <= 0) { sg_remove_scat(schp); return 1; } schp->k_use_sg = res; schp->dio_in_use = 1; hp->info |= SG_INFO_DIRECT_IO; return 0; #else return 1; #endif } static int sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size) { struct scatterlist *sg; int ret_sz = 0, k, rem_sz, num, mx_sc_elems; int sg_tablesize = sfp->parentdp->sg_tablesize; int blk_size = buff_size; struct page *p = NULL; if (blk_size < 0) 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_indirect: buff_size=%d, blk_size=%d\n", buff_size, blk_size)); /* N.B. ret_sz carried into this block ... */ mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize); if (mx_sc_elems < 0) return mx_sc_elems; /* most likely -ENOMEM */ num = scatter_elem_sz; if (unlikely(num != scatter_elem_sz_prev)) { if (num < PAGE_SIZE) { scatter_elem_sz = PAGE_SIZE; scatter_elem_sz_prev = PAGE_SIZE; } else scatter_elem_sz_prev = num; } for (k = 0, sg = schp->buffer, rem_sz = blk_size; (rem_sz > 0) && (k < mx_sc_elems); ++k, rem_sz -= ret_sz, sg = sg_next(sg)) { num = (rem_sz > scatter_elem_sz_prev) ? scatter_elem_sz_prev : rem_sz; p = sg_page_malloc(num, sfp->low_dma, &ret_sz); if (!p) return -ENOMEM; if (num == scatter_elem_sz_prev) { if (unlikely(ret_sz > scatter_elem_sz_prev)) { scatter_elem_sz = ret_sz; scatter_elem_sz_prev = ret_sz; } } sg_set_page(sg, p, (ret_sz > num) ? num : ret_sz, 0); SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k=%d, num=%d, " "ret_sz=%d\n", k, num, ret_sz)); } /* end of for loop */ schp->k_use_sg = k; SCSI_LOG_TIMEOUT(5, printk("sg_build_indirect: k_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 int sg_write_xfer(Sg_request * srp) { sg_io_hdr_t *hp = &srp->header; Sg_scatter_hold *schp = &srp->data; struct scatterlist *sg = schp->buffer; int num_xfer = 0; int j, k, onum, usglen, ksglen, res; int iovec_count = (int) hp->iovec_count; int dxfer_dir = hp->dxfer_direction; unsigned char *p; unsigned char __user *up; int new_interface = ('\0' == hp->interface_id) ? 0 : 1; if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_TO_DEV == dxfer_dir) || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) { num_xfer = (int) (new_interface ? hp->dxfer_len : hp->flags); if (schp->bufflen < num_xfer) num_xfer = schp->bufflen; } if ((num_xfer <= 0) || (schp->dio_in_use) || (new_interface && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags))) return 0; SCSI_LOG_TIMEOUT(4, printk("sg_write_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n", num_xfer, iovec_count, schp->k_use_sg)); if (iovec_count) { onum = iovec_count; if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum)) return -EFAULT; } else onum = 1; ksglen = sg->length; p = page_address(sg_page(sg)); for (j = 0, k = 0; j < onum; ++j) { res = sg_u_iovec(hp, iovec_count, j, 1, &usglen, &up); if (res) return res; for (; p; sg = sg_next(sg), ksglen = sg->length, p = page_address(sg_page(sg))) { if (usglen <= 0) break; if (ksglen > usglen) { if (usglen >= num_xfer) { if (__copy_from_user(p, up, num_xfer)) return -EFAULT; return 0; } if (__copy_from_user(p, up, usglen)) return -EFAULT; p += usglen; ksglen -= usglen; break; } else { if (ksglen >= num_xfer) { if (__copy_from_user(p, up, num_xfer)) return -EFAULT; return 0; } if (__copy_from_user(p, up, ksglen)) return -EFAULT; up += ksglen; usglen -= ksglen; } ++k; if (k >= schp->k_use_sg) return 0; } } return 0; } static int sg_u_iovec(sg_io_hdr_t * hp, int sg_num, int ind, int wr_xf, int *countp, unsigned char __user **up) { int num_xfer = (int) hp->dxfer_len; unsigned char __user *p = hp->dxferp; int count; if (0 == sg_num) { if (wr_xf && ('\0' == hp->interface_id)) count = (int) hp->flags; /* holds "old" input_size */ else count = num_xfer; } else { sg_iovec_t iovec; if (__copy_from_user(&iovec, p + ind*SZ_SG_IOVEC, SZ_SG_IOVEC)) return -EFAULT; p = iovec.iov_base; count = (int) iovec.iov_len; } if (!access_ok(wr_xf ? VERIFY_READ : VERIFY_WRITE, p, count)) return -EFAULT; if (up) *up = p; if (countp) *countp = count; return 0; } static void sg_remove_scat(Sg_scatter_hold * schp) { SCSI_LOG_TIMEOUT(4, printk("sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg)); if (schp->buffer && (schp->sglist_len > 0)) { struct scatterlist *sg = schp->buffer; if (schp->dio_in_use) { #ifdef SG_ALLOW_DIO_CODE st_unmap_user_pages(sg, schp->k_use_sg, TRUE); #endif } else { int k; for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) { SCSI_LOG_TIMEOUT(5, printk( "sg_remove_scat: k=%d, pg=0x%p, len=%d\n", k, sg_page(sg), sg->length)); sg_page_free(sg_page(sg), sg->length); } } kfree(schp->buffer); } memset(schp, 0, sizeof (*schp)); } static int sg_read_xfer(Sg_request * srp) { sg_io_hdr_t *hp = &srp->header; Sg_scatter_hold *schp = &srp->data; struct scatterlist *sg = schp->buffer; int num_xfer = 0; int j, k, onum, usglen, ksglen, res; int iovec_count = (int) hp->iovec_count; int dxfer_dir = hp->dxfer_direction; unsigned char *p; unsigned char __user *up; int new_interface = ('\0' == hp->interface_id) ? 0 : 1; if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir) || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) { num_xfer = hp->dxfer_len; if (schp->bufflen < num_xfer) num_xfer = schp->bufflen; } if ((num_xfer <= 0) || (schp->dio_in_use) || (new_interface && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags))) return 0; SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n", num_xfer, iovec_count, schp->k_use_sg)); if (iovec_count) { onum = iovec_count; if (!access_ok(VERIFY_READ, hp->dxferp, SZ_SG_IOVEC * onum)) return -EFAULT; } else onum = 1; p = page_address(sg_page(sg)); ksglen = sg->length; for (j = 0, k = 0; j < onum; ++j) { res = sg_u_iovec(hp, iovec_count, j, 0, &usglen, &up); if (res) return res; for (; p; sg = sg_next(sg), ksglen = sg->length, p = page_address(sg_page(sg))) { if (usglen <= 0) break; if (ksglen > usglen) { if (usglen >= num_xfer) { if (__copy_to_user(up, p, num_xfer)) return -EFAULT; return 0; } if (__copy_to_user(up, p, usglen)) return -EFAULT; p += usglen; ksglen -= usglen; break; } else { if (ksglen >= num_xfer) { if (__copy_to_user(up, p, num_xfer)) return -EFAULT; return 0; } if (__copy_to_user(up, p, ksglen)) return -EFAULT; up += ksglen; usglen -= ksglen; } ++k; if (k >= schp->k_use_sg) return 0; } } return 0; } static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) { Sg_scatter_hold *schp = &srp->data; struct scatterlist *sg = schp->buffer; int k, num; SCSI_LOG_TIMEOUT(4, printk("sg_read_oxfer: num_read_xfer=%d\n", num_read_xfer)); if ((!outp) || (num_read_xfer <= 0)) return 0; for (k = 0; (k < schp->k_use_sg) && sg_page(sg); ++k, sg = sg_next(sg)) { num = sg->length; if (num > num_read_xfer) { if (__copy_to_user(outp, page_address(sg_page(sg)), num_read_xfer)) return -EFAULT; break; } else { if (__copy_to_user(outp, page_address(sg_page(sg)), num)) return -EFAULT; num_read_xfer -= num; if (num_read_xfer <= 0) break; outp += num; } } return 0; } 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_indirect(schp, sfp, req_size)) 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; struct scatterlist *sg = rsv_schp->buffer; int k, num, rem; srp->res_used = 1; SCSI_LOG_TIMEOUT(4, printk("sg_link_reserve: size=%d\n", size)); rem = size; for (k = 0; k < rsv_schp->k_use_sg; ++k, sg = sg_next(sg)) { num = sg->length; if (rem <= num) { sfp->save_scat_len = num; sg->length = rem; req_schp->k_use_sg = k + 1; req_schp->sglist_len = rsv_schp->sglist_len; req_schp->buffer = rsv_schp->buffer; req_schp->bufflen = size; req_schp->b_malloc_len = rsv_schp->b_malloc_len; break; } else rem -= num; } if (k >= rsv_schp->k_use_sg) SCSI_LOG_TIMEOUT(1, printk("sg_link_reserve: BAD size\n")); } 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->k_use_sg=%d\n", (int) req_schp->k_use_sg)); if ((rsv_schp->k_use_sg > 0) && (req_schp->k_use_sg > 0)) { struct scatterlist *sg = rsv_schp->buffer; if (sfp->save_scat_len > 0) (sg + (req_schp->k_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->k_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_rq_mark(Sg_fd * sfp, int pack_id) { Sg_request *resp; unsigned long iflags; write_lock_irqsave(&sfp->rq_list_lock, iflags); for (resp = sfp->headrp; resp; resp = resp->nextrp) { /* look for requests that are ready + not SG_IO owned */ if ((1 == resp->done) && (!resp->sg_io_owned) && ((-1 == pack_id) || (resp->header.pack_id == pack_id))) { resp->done = 2; /* guard against other readers */ break; } } write_unlock_irqrestore(&sfp->rq_list_lock, iflags); return resp; } #ifdef CONFIG_SCSI_PROC_FS static Sg_request * sg_get_nth_request(Sg_fd * sfp, int nth) { Sg_request *resp; unsigned long iflags; int k; read_lock_irqsave(&sfp->rq_list_lock, iflags); for (k = 0, resp = sfp->headrp; resp && (k < nth); ++k, resp = resp->nextrp) ; read_unlock_irqrestore(&sfp->rq_list_lock, iflags); return resp; } #endif /* always adds to end of list */ static Sg_request * sg_add_request(Sg_fd * sfp) { int k; unsigned long iflags; Sg_request *resp; Sg_request *rp = sfp->req_arr; write_lock_irqsave(&sfp->rq_list_lock, iflags); resp = sfp->headrp; if (!resp) { memset(rp, 0, sizeof (Sg_request)); rp->parentfp = sfp; resp = rp; sfp->headrp = resp; } else { if (0 == sfp->cmd_q) resp = NULL; /* command queuing disallowed */ else { for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) { if (!rp->parentfp) break; } if (k < SG_MAX_QUEUE) { memset(rp, 0, sizeof (Sg_request)); rp->parentfp = sfp; while (resp->nextrp) resp = resp->nextrp; resp->nextrp = rp; resp = rp; } else resp = NULL; } } if (resp) { resp->nextrp = NULL; resp->header.duration = jiffies_to_msecs(jiffies); } write_unlock_irqrestore(&sfp->rq_list_lock, iflags); return resp; } /* Return of 1 for found; 0 for not found */ static int sg_remove_request(Sg_fd * sfp, Sg_request * srp) { Sg_request *prev_rp; Sg_request *rp; unsigned long iflags; int res = 0; if ((!sfp) || (!srp) || (!sfp->headrp)) return res; write_lock_irqsave(&sfp->rq_list_lock, iflags); prev_rp = sfp->headrp; if (srp == prev_rp) { sfp->headrp = prev_rp->nextrp; prev_rp->parentfp = NULL; res = 1; } else { while ((rp = prev_rp->nextrp)) { if (srp == rp) { prev_rp->nextrp = rp->nextrp; rp->parentfp = NULL; res = 1; break; } prev_rp = rp; } } write_unlock_irqrestore(&sfp->rq_list_lock, iflags); return res; } #ifdef CONFIG_SCSI_PROC_FS static Sg_fd * sg_get_nth_sfp(Sg_device * sdp, int nth) { Sg_fd *resp; unsigned long iflags; int k; read_lock_irqsave(&sg_index_lock, iflags); for (k = 0, resp = sdp->headfp; resp && (k < nth); ++k, resp = resp->nextfp) ; read_unlock_irqrestore(&sg_index_lock, iflags); return resp; } #endif static Sg_fd * sg_add_sfp(Sg_device * sdp, int dev) { Sg_fd *sfp; unsigned long iflags; int bufflen; sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN); if (!sfp) return NULL; init_waitqueue_head(&sfp->read_wait); rwlock_init(&sfp->rq_list_lock); 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_index_lock, iflags); 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; } 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; bufflen = min_t(int, sg_big_buff, sdp->device->request_queue->max_sectors * 512); sg_build_reserve(sfp, bufflen); SCSI_LOG_TIMEOUT(3, printk("sg_add_sfp: bufflen=%d, k_use_sg=%d\n", sfp->reserve.bufflen, sfp->reserve.k_use_sg)); return sfp; } static void __sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp) { Sg_fd *fp; Sg_fd *prev_fp; 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, k_use_sg=%d\n", (int) sfp->reserve.bufflen, (int) sfp->reserve.k_use_sg)); sg_remove_scat(&sfp->reserve); } sfp->parentdp = NULL; SCSI_LOG_TIMEOUT(6, printk("__sg_remove_sfp: sfp=0x%p\n", sfp)); kfree(sfp); } /* Returns 0 in normal case, 1 when detached and sdp object removed */ static int sg_remove_sfp(Sg_device * sdp, Sg_fd * sfp) { Sg_request *srp; Sg_request *tsrp; int dirty = 0; int res = 0; for (srp = sfp->headrp; srp; srp = tsrp) { tsrp = srp->nextrp; if (sg_srp_done(srp, sfp)) sg_finish_rem_req(srp); else ++dirty; } if (0 == dirty) { unsigned long iflags; write_lock_irqsave(&sg_index_lock, iflags); __sg_remove_sfp(sdp, sfp); if (sdp->detached && (NULL == sdp->headfp)) { idr_remove(&sg_index_idr, sdp->index); kfree(sdp); res = 1; } 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 * throwing another counter on the host module */ scsi_device_get(sdp->device); /* XXX: retval ignored? */ 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(Sg_fd * sfp) { const Sg_request *srp; unsigned long iflags; read_lock_irqsave(&sfp->rq_list_lock, iflags); for (srp = sfp->headrp; srp; srp = srp->nextrp) if (srp->res_used) break; read_unlock_irqrestore(&sfp->rq_list_lock, iflags); return srp ? 1 : 0; } /* The size fetched (value output via retSzp) set when non-NULL return */ static struct page * sg_page_malloc(int rqSz, int lowDma, int *retSzp) { struct page *resp = NULL; gfp_t page_mask; int order, a_size; int resSz; if ((rqSz <= 0) || (NULL == retSzp)) return resp; if (lowDma) page_mask = GFP_ATOMIC | GFP_DMA | __GFP_COMP | __GFP_NOWARN; else page_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN; for (order = 0, a_size = PAGE_SIZE; a_size < rqSz; order++, a_size <<= 1) ; resSz = a_size; /* rounded up if necessary */ resp = alloc_pages(page_mask, order); while ((!resp) && order) { --order; a_size >>= 1; /* divide by 2, until PAGE_SIZE */ resp = alloc_pages(page_mask, order); /* try half */ resSz = a_size; } if (resp) { if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) memset(page_address(resp), 0, resSz); *retSzp = resSz; } return resp; } static void sg_page_free(struct page *page, int size) { int order, a_size; if (!page) return; for (order = 0, a_size = PAGE_SIZE; a_size < size; order++, a_size <<= 1) ; __free_pages(page, order); } #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 = -1; unsigned long 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 static Sg_device * sg_get_dev(int dev) { Sg_device *sdp; unsigned long iflags; read_lock_irqsave(&sg_index_lock, iflags); sdp = idr_find(&sg_index_idr, dev); read_unlock_irqrestore(&sg_index_lock, iflags); return sdp; } #ifdef CONFIG_SCSI_PROC_FS static struct proc_dir_entry *sg_proc_sgp = NULL; static char sg_proc_sg_dirname[] = "scsi/sg"; static int sg_proc_seq_show_int(struct seq_file *s, void *v); static int sg_proc_single_open_adio(struct inode *inode, struct file *file); static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, size_t count, loff_t *off); static struct file_operations adio_fops = { /* .owner, .read and .llseek added in sg_proc_init() */ .open = sg_proc_single_open_adio, .write = sg_proc_write_adio, .release = single_release, }; static int sg_proc_single_open_dressz(struct inode *inode, struct file *file); static ssize_t sg_proc_write_dressz(struct file *filp, const char __user *buffer, size_t count, loff_t *off); static struct file_operations dressz_fops = { .open = sg_proc_single_open_dressz, .write = sg_proc_write_dressz, .release = single_release, }; static int sg_proc_seq_show_version(struct seq_file *s, void *v); static int sg_proc_single_open_version(struct inode *inode, struct file *file); static struct file_operations version_fops = { .open = sg_proc_single_open_version, .release = single_release, }; static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v); static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file); static struct file_operations devhdr_fops = { .open = sg_proc_single_open_devhdr, .release = single_release, }; static int sg_proc_seq_show_dev(struct seq_file *s, void *v); static int sg_proc_open_dev(struct inode *inode, struct file *file); static void * dev_seq_start(struct seq_file *s, loff_t *pos); static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos); static void dev_seq_stop(struct seq_file *s, void *v); static struct file_operations dev_fops = { .open = sg_proc_open_dev, .release = seq_release, }; static struct seq_operations dev_seq_ops = { .start = dev_seq_start, .next = dev_seq_next, .stop = dev_seq_stop, .show = sg_proc_seq_show_dev, }; static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v); static int sg_proc_open_devstrs(struct inode *inode, struct file *file); static struct file_operations devstrs_fops = { .open = sg_proc_open_devstrs, .release = seq_release, }; static struct seq_operations devstrs_seq_ops = { .start = dev_seq_start, .next = dev_seq_next, .stop = dev_seq_stop, .show = sg_proc_seq_show_devstrs, }; static int sg_proc_seq_show_debug(struct seq_file *s, void *v); static int sg_proc_open_debug(struct inode *inode, struct file *file); static struct file_operations debug_fops = { .open = sg_proc_open_debug, .release = seq_release, }; static struct seq_operations debug_seq_ops = { .start = dev_seq_start, .next = dev_seq_next, .stop = dev_seq_stop, .show = sg_proc_seq_show_debug, }; struct sg_proc_leaf { const char * name; struct file_operations * fops; }; static struct sg_proc_leaf sg_proc_leaf_arr[] = { {"allow_dio", &adio_fops}, {"debug", &debug_fops}, {"def_reserved_size", &dressz_fops}, {"device_hdr", &devhdr_fops}, {"devices", &dev_fops}, {"device_strs", &devstrs_fops}, {"version", &version_fops} }; static int sg_proc_init(void) { int k, mask; int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr); struct sg_proc_leaf * leaf; sg_proc_sgp = proc_mkdir(sg_proc_sg_dirname, NULL); if (!sg_proc_sgp) return 1; for (k = 0; k < num_leaves; ++k) { leaf = &sg_proc_leaf_arr[k]; mask = leaf->fops->write ? S_IRUGO | S_IWUSR : S_IRUGO; leaf->fops->owner = THIS_MODULE; leaf->fops->read = seq_read; leaf->fops->llseek = seq_lseek; proc_create(leaf->name, mask, sg_proc_sgp, leaf->fops); } return 0; } static void sg_proc_cleanup(void) { int k; int num_leaves = ARRAY_SIZE(sg_proc_leaf_arr); if (!sg_proc_sgp) return; for (k = 0; k < num_leaves; ++k) remove_proc_entry(sg_proc_leaf_arr[k].name, sg_proc_sgp); remove_proc_entry(sg_proc_sg_dirname, NULL); } static int sg_proc_seq_show_int(struct seq_file *s, void *v) { seq_printf(s, "%d\n", *((int *)s->private)); return 0; } static int sg_proc_single_open_adio(struct inode *inode, struct file *file) { return single_open(file, sg_proc_seq_show_int, &sg_allow_dio); } static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer, size_t count, loff_t *off) { int num; char buff[11]; if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; num = (count < 10) ? count : 10; if (copy_from_user(buff, buffer, num)) return -EFAULT; buff[num] = '\0'; sg_allow_dio = simple_strtoul(buff, NULL, 10) ? 1 : 0; return count; } static int sg_proc_single_open_dressz(struct inode *inode, struct file *file) { return single_open(file, sg_proc_seq_show_int, &sg_big_buff); } static ssize_t sg_proc_write_dressz(struct file *filp, const char __user *buffer, size_t count, loff_t *off) { int num; unsigned long k = ULONG_MAX; char buff[11]; if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; num = (count < 10) ? count : 10; if (copy_from_user(buff, buffer, num)) return -EFAULT; buff[num] = '\0'; k = simple_strtoul(buff, NULL, 10); if (k <= 1048576) { /* limit "big buff" to 1 MB */ sg_big_buff = k; return count; } return -ERANGE; } static int sg_proc_seq_show_version(struct seq_file *s, void *v) { seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR, sg_version_date); return 0; } static int sg_proc_single_open_version(struct inode *inode, struct file *file) { return single_open(file, sg_proc_seq_show_version, NULL); } static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v) { seq_printf(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\t" "online\n"); return 0; } static int sg_proc_single_open_devhdr(struct inode *inode, struct file *file) { return single_open(file, sg_proc_seq_show_devhdr, NULL); } struct sg_proc_deviter { loff_t index; size_t max; }; static void * dev_seq_start(struct seq_file *s, loff_t *pos) { struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL); s->private = it; if (! it) return NULL; it->index = *pos; it->max = sg_last_dev(); if (it->index >= it->max) return NULL; return it; } static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos) { struct sg_proc_deviter * it = s->private; *pos = ++it->index; return (it->index < it->max) ? it : NULL; } static void dev_seq_stop(struct seq_file *s, void *v) { kfree(s->private); } static int sg_proc_open_dev(struct inode *inode, struct file *file) { return seq_open(file, &dev_seq_ops); } static int sg_proc_seq_show_dev(struct seq_file *s, void *v) { struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; Sg_device *sdp; struct scsi_device *scsidp; sdp = it ? sg_get_dev(it->index) : NULL; if (sdp && (scsidp = sdp->device) && (!sdp->detached)) seq_printf(s, "%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, 1, (int) scsidp->queue_depth, (int) scsidp->device_busy, (int) scsi_device_online(scsidp)); else seq_printf(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n"); return 0; } static int sg_proc_open_devstrs(struct inode *inode, struct file *file) { return seq_open(file, &devstrs_seq_ops); } static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v) { struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; Sg_device *sdp; struct scsi_device *scsidp; sdp = it ? sg_get_dev(it->index) : NULL; if (sdp && (scsidp = sdp->device) && (!sdp->detached)) seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n", scsidp->vendor, scsidp->model, scsidp->rev); else seq_printf(s, "<no active device>\n"); return 0; } static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp) { int k, m, new_interface, blen, usg; Sg_request *srp; Sg_fd *fp; const sg_io_hdr_t *hp; const char * cp; unsigned int ms; for (k = 0; (fp = sg_get_nth_sfp(sdp, k)); ++k) { seq_printf(s, " FD(%d): timeout=%dms bufflen=%d " "(res)sgat=%d low_dma=%d\n", k + 1, jiffies_to_msecs(fp->timeout), fp->reserve.bufflen, (int) fp->reserve.k_use_sg, (int) fp->low_dma); seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=%d\n", (int) fp->cmd_q, (int) fp->force_packid, (int) fp->keep_orphan, (int) fp->closed); for (m = 0; (srp = sg_get_nth_request(fp, m)); ++m) { hp = &srp->header; new_interface = (hp->interface_id == '\0') ? 0 : 1; if (srp->res_used) { if (new_interface && (SG_FLAG_MMAP_IO & hp->flags)) cp = " mmap>> "; else cp = " rb>> "; } else { if (SG_INFO_DIRECT_IO_MASK & hp->info) cp = " dio>> "; else cp = " "; } seq_printf(s, cp); blen = srp->data.bufflen; usg = srp->data.k_use_sg; seq_printf(s, srp->done ? ((1 == srp->done) ? "rcv:" : "fin:") : "act:"); seq_printf(s, " id=%d blen=%d", srp->header.pack_id, blen); if (srp->done) seq_printf(s, " dur=%d", hp->duration); else { ms = jiffies_to_msecs(jiffies); seq_printf(s, " t_o/elap=%d/%d", (new_interface ? hp->timeout : jiffies_to_msecs(fp->timeout)), (ms > hp->duration ? ms - hp->duration : 0)); } seq_printf(s, "ms sgat=%d op=0x%02x\n", usg, (int) srp->data.cmd_opcode); } if (0 == m) seq_printf(s, " No requests active\n"); } } static int sg_proc_open_debug(struct inode *inode, struct file *file) { return seq_open(file, &debug_seq_ops); } static int sg_proc_seq_show_debug(struct seq_file *s, void *v) { struct sg_proc_deviter * it = (struct sg_proc_deviter *) v; Sg_device *sdp; if (it && (0 == it->index)) { 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; if (sdp) { struct scsi_device *scsidp = sdp->device; if (NULL == scsidp) { seq_printf(s, "device %d detached ??\n", (int)it->index); return 0; } if (sg_get_nth_sfp(sdp, 0)) { seq_printf(s, " >>> device=%s ", sdp->disk->disk_name); if (sdp->detached) seq_printf(s, "detached pending close "); else seq_printf (s, "scsi%d chan=%d id=%d lun=%d em=%d", scsidp->host->host_no, scsidp->channel, scsidp->id, scsidp->lun, scsidp->host->hostt->emulated); seq_printf(s, " sg_tablesize=%d excl=%d\n", sdp->sg_tablesize, sdp->exclude); } sg_proc_debug_helper(s, sdp); } return 0; } #endif /* CONFIG_SCSI_PROC_FS */ module_init(init_sg); module_exit(exit_sg);