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Diffstat (limited to 'drivers/block/paride/pf.c')
| -rw-r--r-- | drivers/block/paride/pf.c | 1080 |
1 files changed, 1080 insertions, 0 deletions
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c new file mode 100644 index 000000000..bb09f21ce --- /dev/null +++ b/drivers/block/paride/pf.c @@ -0,0 +1,1080 @@ +/* + pf.c (c) 1997-8 Grant R. Guenther <grant@torque.net> + Under the terms of the GNU General Public License. + + This is the high-level driver for parallel port ATAPI disk + drives based on chips supported by the paride module. + + By default, the driver will autoprobe for a single parallel + port ATAPI disk drive, but if their individual parameters are + specified, the driver can handle up to 4 drives. + + The behaviour of the pf driver can be altered by setting + some parameters from the insmod command line. The following + parameters are adjustable: + + drive0 These four arguments can be arrays of + drive1 1-7 integers as follows: + drive2 + drive3 <prt>,<pro>,<uni>,<mod>,<slv>,<lun>,<dly> + + Where, + + <prt> is the base of the parallel port address for + the corresponding drive. (required) + + <pro> is the protocol number for the adapter that + supports this drive. These numbers are + logged by 'paride' when the protocol modules + are initialised. (0 if not given) + + <uni> for those adapters that support chained + devices, this is the unit selector for the + chain of devices on the given port. It should + be zero for devices that don't support chaining. + (0 if not given) + + <mod> this can be -1 to choose the best mode, or one + of the mode numbers supported by the adapter. + (-1 if not given) + + <slv> ATAPI CDroms can be jumpered to master or slave. + Set this to 0 to choose the master drive, 1 to + choose the slave, -1 (the default) to choose the + first drive found. + + <lun> Some ATAPI devices support multiple LUNs. + One example is the ATAPI PD/CD drive from + Matshita/Panasonic. This device has a + CD drive on LUN 0 and a PD drive on LUN 1. + By default, the driver will search for the + first LUN with a supported device. Set + this parameter to force it to use a specific + LUN. (default -1) + + <dly> some parallel ports require the driver to + go more slowly. -1 sets a default value that + should work with the chosen protocol. Otherwise, + set this to a small integer, the larger it is + the slower the port i/o. In some cases, setting + this to zero will speed up the device. (default -1) + + major You may use this parameter to override the + default major number (47) that this driver + will use. Be sure to change the device + name as well. + + name This parameter is a character string that + contains the name the kernel will use for this + device (in /proc output, for instance). + (default "pf"). + + cluster The driver will attempt to aggregate requests + for adjacent blocks into larger multi-block + clusters. The maximum cluster size (in 512 + byte sectors) is set with this parameter. + (default 64) + + verbose This parameter controls the amount of logging + that the driver will do. Set it to 0 for + normal operation, 1 to see autoprobe progress + messages, or 2 to see additional debugging + output. (default 0) + + nice This parameter controls the driver's use of + idle CPU time, at the expense of some speed. + + If this driver is built into the kernel, you can use the + following command line parameters, with the same values + as the corresponding module parameters listed above: + + pf.drive0 + pf.drive1 + pf.drive2 + pf.drive3 + pf.cluster + pf.nice + + In addition, you can use the parameter pf.disable to disable + the driver entirely. + +*/ + +/* Changes: + + 1.01 GRG 1998.05.03 Changes for SMP. Eliminate sti(). + Fix for drives that don't clear STAT_ERR + until after next CDB delivered. + Small change in pf_completion to round + up transfer size. + 1.02 GRG 1998.06.16 Eliminated an Ugh + 1.03 GRG 1998.08.16 Use HZ in loop timings, extra debugging + 1.04 GRG 1998.09.24 Added jumbo support + +*/ + +#define PF_VERSION "1.04" +#define PF_MAJOR 47 +#define PF_NAME "pf" +#define PF_UNITS 4 + +#include <linux/types.h> + +/* Here are things one can override from the insmod command. + Most are autoprobed by paride unless set here. Verbose is off + by default. + +*/ + +static bool verbose = 0; +static int major = PF_MAJOR; +static char *name = PF_NAME; +static int cluster = 64; +static int nice = 0; +static int disable = 0; + +static int drive0[7] = { 0, 0, 0, -1, -1, -1, -1 }; +static int drive1[7] = { 0, 0, 0, -1, -1, -1, -1 }; +static int drive2[7] = { 0, 0, 0, -1, -1, -1, -1 }; +static int drive3[7] = { 0, 0, 0, -1, -1, -1, -1 }; + +static int (*drives[4])[7] = {&drive0, &drive1, &drive2, &drive3}; +static int pf_drive_count; + +enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_LUN, D_DLY}; + +/* end of parameters */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/delay.h> +#include <linux/hdreg.h> +#include <linux/cdrom.h> +#include <linux/spinlock.h> +#include <linux/blk-mq.h> +#include <linux/blkpg.h> +#include <linux/mutex.h> +#include <linux/uaccess.h> + +static DEFINE_MUTEX(pf_mutex); +static DEFINE_SPINLOCK(pf_spin_lock); + +module_param(verbose, bool, 0644); +module_param(major, int, 0); +module_param(name, charp, 0); +module_param(cluster, int, 0); +module_param(nice, int, 0); +module_param_array(drive0, int, NULL, 0); +module_param_array(drive1, int, NULL, 0); +module_param_array(drive2, int, NULL, 0); +module_param_array(drive3, int, NULL, 0); + +#include "paride.h" +#include "pseudo.h" + +/* constants for faking geometry numbers */ + +#define PF_FD_MAX 8192 /* use FD geometry under this size */ +#define PF_FD_HDS 2 +#define PF_FD_SPT 18 +#define PF_HD_HDS 64 +#define PF_HD_SPT 32 + +#define PF_MAX_RETRIES 5 +#define PF_TMO 800 /* interrupt timeout in jiffies */ +#define PF_SPIN_DEL 50 /* spin delay in micro-seconds */ + +#define PF_SPIN (1000000*PF_TMO)/(HZ*PF_SPIN_DEL) + +#define STAT_ERR 0x00001 +#define STAT_INDEX 0x00002 +#define STAT_ECC 0x00004 +#define STAT_DRQ 0x00008 +#define STAT_SEEK 0x00010 +#define STAT_WRERR 0x00020 +#define STAT_READY 0x00040 +#define STAT_BUSY 0x00080 + +#define ATAPI_REQ_SENSE 0x03 +#define ATAPI_LOCK 0x1e +#define ATAPI_DOOR 0x1b +#define ATAPI_MODE_SENSE 0x5a +#define ATAPI_CAPACITY 0x25 +#define ATAPI_IDENTIFY 0x12 +#define ATAPI_READ_10 0x28 +#define ATAPI_WRITE_10 0x2a + +static int pf_open(struct block_device *bdev, fmode_t mode); +static blk_status_t pf_queue_rq(struct blk_mq_hw_ctx *hctx, + const struct blk_mq_queue_data *bd); +static int pf_ioctl(struct block_device *bdev, fmode_t mode, + unsigned int cmd, unsigned long arg); +static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo); + +static void pf_release(struct gendisk *disk, fmode_t mode); + +static int pf_detect(void); +static void do_pf_read(void); +static void do_pf_read_start(void); +static void do_pf_write(void); +static void do_pf_write_start(void); +static void do_pf_read_drq(void); +static void do_pf_write_done(void); + +#define PF_NM 0 +#define PF_RO 1 +#define PF_RW 2 + +#define PF_NAMELEN 8 + +struct pf_unit { + struct pi_adapter pia; /* interface to paride layer */ + struct pi_adapter *pi; + int removable; /* removable media device ? */ + int media_status; /* media present ? WP ? */ + int drive; /* drive */ + int lun; + int access; /* count of active opens ... */ + int present; /* device present ? */ + char name[PF_NAMELEN]; /* pf0, pf1, ... */ + struct gendisk *disk; + struct blk_mq_tag_set tag_set; + struct list_head rq_list; +}; + +static struct pf_unit units[PF_UNITS]; + +static int pf_identify(struct pf_unit *pf); +static void pf_lock(struct pf_unit *pf, int func); +static void pf_eject(struct pf_unit *pf); +static unsigned int pf_check_events(struct gendisk *disk, + unsigned int clearing); + +static char pf_scratch[512]; /* scratch block buffer */ + +/* the variables below are used mainly in the I/O request engine, which + processes only one request at a time. +*/ + +static int pf_retries = 0; /* i/o error retry count */ +static int pf_busy = 0; /* request being processed ? */ +static struct request *pf_req; /* current request */ +static int pf_block; /* address of next requested block */ +static int pf_count; /* number of blocks still to do */ +static int pf_run; /* sectors in current cluster */ +static int pf_cmd; /* current command READ/WRITE */ +static struct pf_unit *pf_current;/* unit of current request */ +static int pf_mask; /* stopper for pseudo-int */ +static char *pf_buf; /* buffer for request in progress */ +static void *par_drv; /* reference of parport driver */ + +/* kernel glue structures */ + +static const struct block_device_operations pf_fops = { + .owner = THIS_MODULE, + .open = pf_open, + .release = pf_release, + .ioctl = pf_ioctl, + .compat_ioctl = pf_ioctl, + .getgeo = pf_getgeo, + .check_events = pf_check_events, +}; + +static const struct blk_mq_ops pf_mq_ops = { + .queue_rq = pf_queue_rq, +}; + +static void __init pf_init_units(void) +{ + struct pf_unit *pf; + int unit; + + pf_drive_count = 0; + for (unit = 0, pf = units; unit < PF_UNITS; unit++, pf++) { + struct gendisk *disk; + + disk = alloc_disk(1); + if (!disk) + continue; + + disk->queue = blk_mq_init_sq_queue(&pf->tag_set, &pf_mq_ops, + 1, BLK_MQ_F_SHOULD_MERGE); + if (IS_ERR(disk->queue)) { + disk->queue = NULL; + put_disk(disk); + continue; + } + + INIT_LIST_HEAD(&pf->rq_list); + disk->queue->queuedata = pf; + blk_queue_max_segments(disk->queue, cluster); + blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH); + pf->disk = disk; + pf->pi = &pf->pia; + pf->media_status = PF_NM; + pf->drive = (*drives[unit])[D_SLV]; + pf->lun = (*drives[unit])[D_LUN]; + snprintf(pf->name, PF_NAMELEN, "%s%d", name, unit); + disk->major = major; + disk->first_minor = unit; + strcpy(disk->disk_name, pf->name); + disk->fops = &pf_fops; + disk->events = DISK_EVENT_MEDIA_CHANGE; + if (!(*drives[unit])[D_PRT]) + pf_drive_count++; + } +} + +static int pf_open(struct block_device *bdev, fmode_t mode) +{ + struct pf_unit *pf = bdev->bd_disk->private_data; + int ret; + + mutex_lock(&pf_mutex); + pf_identify(pf); + + ret = -ENODEV; + if (pf->media_status == PF_NM) + goto out; + + ret = -EROFS; + if ((pf->media_status == PF_RO) && (mode & FMODE_WRITE)) + goto out; + + ret = 0; + pf->access++; + if (pf->removable) + pf_lock(pf, 1); +out: + mutex_unlock(&pf_mutex); + return ret; +} + +static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo) +{ + struct pf_unit *pf = bdev->bd_disk->private_data; + sector_t capacity = get_capacity(pf->disk); + + if (capacity < PF_FD_MAX) { + geo->cylinders = sector_div(capacity, PF_FD_HDS * PF_FD_SPT); + geo->heads = PF_FD_HDS; + geo->sectors = PF_FD_SPT; + } else { + geo->cylinders = sector_div(capacity, PF_HD_HDS * PF_HD_SPT); + geo->heads = PF_HD_HDS; + geo->sectors = PF_HD_SPT; + } + + return 0; +} + +static int pf_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg) +{ + struct pf_unit *pf = bdev->bd_disk->private_data; + + if (cmd != CDROMEJECT) + return -EINVAL; + + if (pf->access != 1) + return -EBUSY; + mutex_lock(&pf_mutex); + pf_eject(pf); + mutex_unlock(&pf_mutex); + + return 0; +} + +static void pf_release(struct gendisk *disk, fmode_t mode) +{ + struct pf_unit *pf = disk->private_data; + + mutex_lock(&pf_mutex); + if (pf->access <= 0) { + mutex_unlock(&pf_mutex); + WARN_ON(1); + return; + } + + pf->access--; + + if (!pf->access && pf->removable) + pf_lock(pf, 0); + + mutex_unlock(&pf_mutex); +} + +static unsigned int pf_check_events(struct gendisk *disk, unsigned int clearing) +{ + return DISK_EVENT_MEDIA_CHANGE; +} + +static inline int status_reg(struct pf_unit *pf) +{ + return pi_read_regr(pf->pi, 1, 6); +} + +static inline int read_reg(struct pf_unit *pf, int reg) +{ + return pi_read_regr(pf->pi, 0, reg); +} + +static inline void write_reg(struct pf_unit *pf, int reg, int val) +{ + pi_write_regr(pf->pi, 0, reg, val); +} + +static int pf_wait(struct pf_unit *pf, int go, int stop, char *fun, char *msg) +{ + int j, r, e, s, p; + + j = 0; + while ((((r = status_reg(pf)) & go) || (stop && (!(r & stop)))) + && (j++ < PF_SPIN)) + udelay(PF_SPIN_DEL); + + if ((r & (STAT_ERR & stop)) || (j > PF_SPIN)) { + s = read_reg(pf, 7); + e = read_reg(pf, 1); + p = read_reg(pf, 2); + if (j > PF_SPIN) + e |= 0x100; + if (fun) + printk("%s: %s %s: alt=0x%x stat=0x%x err=0x%x" + " loop=%d phase=%d\n", + pf->name, fun, msg, r, s, e, j, p); + return (e << 8) + s; + } + return 0; +} + +static int pf_command(struct pf_unit *pf, char *cmd, int dlen, char *fun) +{ + pi_connect(pf->pi); + + write_reg(pf, 6, 0xa0+0x10*pf->drive); + + if (pf_wait(pf, STAT_BUSY | STAT_DRQ, 0, fun, "before command")) { + pi_disconnect(pf->pi); + return -1; + } + + write_reg(pf, 4, dlen % 256); + write_reg(pf, 5, dlen / 256); + write_reg(pf, 7, 0xa0); /* ATAPI packet command */ + + if (pf_wait(pf, STAT_BUSY, STAT_DRQ, fun, "command DRQ")) { + pi_disconnect(pf->pi); + return -1; + } + + if (read_reg(pf, 2) != 1) { + printk("%s: %s: command phase error\n", pf->name, fun); + pi_disconnect(pf->pi); + return -1; + } + + pi_write_block(pf->pi, cmd, 12); + + return 0; +} + +static int pf_completion(struct pf_unit *pf, char *buf, char *fun) +{ + int r, s, n; + + r = pf_wait(pf, STAT_BUSY, STAT_DRQ | STAT_READY | STAT_ERR, + fun, "completion"); + + if ((read_reg(pf, 2) & 2) && (read_reg(pf, 7) & STAT_DRQ)) { + n = (((read_reg(pf, 4) + 256 * read_reg(pf, 5)) + + 3) & 0xfffc); + pi_read_block(pf->pi, buf, n); + } + + s = pf_wait(pf, STAT_BUSY, STAT_READY | STAT_ERR, fun, "data done"); + + pi_disconnect(pf->pi); + + return (r ? r : s); +} + +static void pf_req_sense(struct pf_unit *pf, int quiet) +{ + char rs_cmd[12] = + { ATAPI_REQ_SENSE, pf->lun << 5, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0 }; + char buf[16]; + int r; + + r = pf_command(pf, rs_cmd, 16, "Request sense"); + mdelay(1); + if (!r) + pf_completion(pf, buf, "Request sense"); + + if ((!r) && (!quiet)) + printk("%s: Sense key: %x, ASC: %x, ASQ: %x\n", + pf->name, buf[2] & 0xf, buf[12], buf[13]); +} + +static int pf_atapi(struct pf_unit *pf, char *cmd, int dlen, char *buf, char *fun) +{ + int r; + + r = pf_command(pf, cmd, dlen, fun); + mdelay(1); + if (!r) + r = pf_completion(pf, buf, fun); + if (r) + pf_req_sense(pf, !fun); + + return r; +} + +static void pf_lock(struct pf_unit *pf, int func) +{ + char lo_cmd[12] = { ATAPI_LOCK, pf->lun << 5, 0, 0, func, 0, 0, 0, 0, 0, 0, 0 }; + + pf_atapi(pf, lo_cmd, 0, pf_scratch, func ? "lock" : "unlock"); +} + +static void pf_eject(struct pf_unit *pf) +{ + char ej_cmd[12] = { ATAPI_DOOR, pf->lun << 5, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0 }; + + pf_lock(pf, 0); + pf_atapi(pf, ej_cmd, 0, pf_scratch, "eject"); +} + +#define PF_RESET_TMO 30 /* in tenths of a second */ + +static void pf_sleep(int cs) +{ + schedule_timeout_interruptible(cs); +} + +/* the ATAPI standard actually specifies the contents of all 7 registers + after a reset, but the specification is ambiguous concerning the last + two bytes, and different drives interpret the standard differently. + */ + +static int pf_reset(struct pf_unit *pf) +{ + int i, k, flg; + int expect[5] = { 1, 1, 1, 0x14, 0xeb }; + + pi_connect(pf->pi); + write_reg(pf, 6, 0xa0+0x10*pf->drive); + write_reg(pf, 7, 8); + + pf_sleep(20 * HZ / 1000); + + k = 0; + while ((k++ < PF_RESET_TMO) && (status_reg(pf) & STAT_BUSY)) + pf_sleep(HZ / 10); + + flg = 1; + for (i = 0; i < 5; i++) + flg &= (read_reg(pf, i + 1) == expect[i]); + + if (verbose) { + printk("%s: Reset (%d) signature = ", pf->name, k); + for (i = 0; i < 5; i++) + printk("%3x", read_reg(pf, i + 1)); + if (!flg) + printk(" (incorrect)"); + printk("\n"); + } + + pi_disconnect(pf->pi); + return flg - 1; +} + +static void pf_mode_sense(struct pf_unit *pf) +{ + char ms_cmd[12] = + { ATAPI_MODE_SENSE, pf->lun << 5, 0, 0, 0, 0, 0, 0, 8, 0, 0, 0 }; + char buf[8]; + + pf_atapi(pf, ms_cmd, 8, buf, "mode sense"); + pf->media_status = PF_RW; + if (buf[3] & 0x80) + pf->media_status = PF_RO; +} + +static void xs(char *buf, char *targ, int offs, int len) +{ + int j, k, l; + + j = 0; + l = 0; + for (k = 0; k < len; k++) + if ((buf[k + offs] != 0x20) || (buf[k + offs] != l)) + l = targ[j++] = buf[k + offs]; + if (l == 0x20) + j--; + targ[j] = 0; +} + +static int xl(char *buf, int offs) +{ + int v, k; + + v = 0; + for (k = 0; k < 4; k++) + v = v * 256 + (buf[k + offs] & 0xff); + return v; +} + +static void pf_get_capacity(struct pf_unit *pf) +{ + char rc_cmd[12] = { ATAPI_CAPACITY, pf->lun << 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; + char buf[8]; + int bs; + + if (pf_atapi(pf, rc_cmd, 8, buf, "get capacity")) { + pf->media_status = PF_NM; + return; + } + set_capacity(pf->disk, xl(buf, 0) + 1); + bs = xl(buf, 4); + if (bs != 512) { + set_capacity(pf->disk, 0); + if (verbose) + printk("%s: Drive %d, LUN %d," + " unsupported block size %d\n", + pf->name, pf->drive, pf->lun, bs); + } +} + +static int pf_identify(struct pf_unit *pf) +{ + int dt, s; + char *ms[2] = { "master", "slave" }; + char mf[10], id[18]; + char id_cmd[12] = + { ATAPI_IDENTIFY, pf->lun << 5, 0, 0, 36, 0, 0, 0, 0, 0, 0, 0 }; + char buf[36]; + + s = pf_atapi(pf, id_cmd, 36, buf, "identify"); + if (s) + return -1; + + dt = buf[0] & 0x1f; + if ((dt != 0) && (dt != 7)) { + if (verbose) + printk("%s: Drive %d, LUN %d, unsupported type %d\n", + pf->name, pf->drive, pf->lun, dt); + return -1; + } + + xs(buf, mf, 8, 8); + xs(buf, id, 16, 16); + + pf->removable = (buf[1] & 0x80); + + pf_mode_sense(pf); + pf_mode_sense(pf); + pf_mode_sense(pf); + + pf_get_capacity(pf); + + printk("%s: %s %s, %s LUN %d, type %d", + pf->name, mf, id, ms[pf->drive], pf->lun, dt); + if (pf->removable) + printk(", removable"); + if (pf->media_status == PF_NM) + printk(", no media\n"); + else { + if (pf->media_status == PF_RO) + printk(", RO"); + printk(", %llu blocks\n", + (unsigned long long)get_capacity(pf->disk)); + } + return 0; +} + +/* returns 0, with id set if drive is detected + -1, if drive detection failed +*/ +static int pf_probe(struct pf_unit *pf) +{ + if (pf->drive == -1) { + for (pf->drive = 0; pf->drive <= 1; pf->drive++) + if (!pf_reset(pf)) { + if (pf->lun != -1) + return pf_identify(pf); + else + for (pf->lun = 0; pf->lun < 8; pf->lun++) + if (!pf_identify(pf)) + return 0; + } + } else { + if (pf_reset(pf)) + return -1; + if (pf->lun != -1) + return pf_identify(pf); + for (pf->lun = 0; pf->lun < 8; pf->lun++) + if (!pf_identify(pf)) + return 0; + } + return -1; +} + +static int pf_detect(void) +{ + struct pf_unit *pf = units; + int k, unit; + + printk("%s: %s version %s, major %d, cluster %d, nice %d\n", + name, name, PF_VERSION, major, cluster, nice); + + par_drv = pi_register_driver(name); + if (!par_drv) { + pr_err("failed to register %s driver\n", name); + return -1; + } + k = 0; + if (pf_drive_count == 0) { + if (pi_init(pf->pi, 1, -1, -1, -1, -1, -1, pf_scratch, PI_PF, + verbose, pf->name)) { + if (!pf_probe(pf) && pf->disk) { + pf->present = 1; + k++; + } else + pi_release(pf->pi); + } + + } else + for (unit = 0; unit < PF_UNITS; unit++, pf++) { + int *conf = *drives[unit]; + if (!conf[D_PRT]) + continue; + if (pi_init(pf->pi, 0, conf[D_PRT], conf[D_MOD], + conf[D_UNI], conf[D_PRO], conf[D_DLY], + pf_scratch, PI_PF, verbose, pf->name)) { + if (pf->disk && !pf_probe(pf)) { + pf->present = 1; + k++; + } else + pi_release(pf->pi); + } + } + if (k) + return 0; + + printk("%s: No ATAPI disk detected\n", name); + for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) { + if (!pf->disk) + continue; + blk_cleanup_queue(pf->disk->queue); + pf->disk->queue = NULL; + blk_mq_free_tag_set(&pf->tag_set); + put_disk(pf->disk); + } + pi_unregister_driver(par_drv); + return -1; +} + +/* The i/o request engine */ + +static int pf_start(struct pf_unit *pf, int cmd, int b, int c) +{ + int i; + char io_cmd[12] = { cmd, pf->lun << 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; + + for (i = 0; i < 4; i++) { + io_cmd[5 - i] = b & 0xff; + b = b >> 8; + } + + io_cmd[8] = c & 0xff; + io_cmd[7] = (c >> 8) & 0xff; + + i = pf_command(pf, io_cmd, c * 512, "start i/o"); + + mdelay(1); + + return i; +} + +static int pf_ready(void) +{ + return (((status_reg(pf_current) & (STAT_BUSY | pf_mask)) == pf_mask)); +} + +static int pf_queue; + +static int set_next_request(void) +{ + struct pf_unit *pf; + int old_pos = pf_queue; + + do { + pf = &units[pf_queue]; + if (++pf_queue == PF_UNITS) + pf_queue = 0; + if (pf->present && !list_empty(&pf->rq_list)) { + pf_req = list_first_entry(&pf->rq_list, struct request, + queuelist); + list_del_init(&pf_req->queuelist); + blk_mq_start_request(pf_req); + break; + } + } while (pf_queue != old_pos); + + return pf_req != NULL; +} + +static void pf_end_request(blk_status_t err) +{ + if (!pf_req) + return; + if (!blk_update_request(pf_req, err, blk_rq_cur_bytes(pf_req))) { + __blk_mq_end_request(pf_req, err); + pf_req = NULL; + } +} + +static void pf_request(void) +{ + if (pf_busy) + return; +repeat: + if (!pf_req && !set_next_request()) + return; + + pf_current = pf_req->rq_disk->private_data; + pf_block = blk_rq_pos(pf_req); + pf_run = blk_rq_sectors(pf_req); + pf_count = blk_rq_cur_sectors(pf_req); + + if (pf_block + pf_count > get_capacity(pf_req->rq_disk)) { + pf_end_request(BLK_STS_IOERR); + goto repeat; + } + + pf_cmd = rq_data_dir(pf_req); + pf_buf = bio_data(pf_req->bio); + pf_retries = 0; + + pf_busy = 1; + if (pf_cmd == READ) + pi_do_claimed(pf_current->pi, do_pf_read); + else if (pf_cmd == WRITE) + pi_do_claimed(pf_current->pi, do_pf_write); + else { + pf_busy = 0; + pf_end_request(BLK_STS_IOERR); + goto repeat; + } +} + +static blk_status_t pf_queue_rq(struct blk_mq_hw_ctx *hctx, + const struct blk_mq_queue_data *bd) +{ + struct pf_unit *pf = hctx->queue->queuedata; + + spin_lock_irq(&pf_spin_lock); + list_add_tail(&bd->rq->queuelist, &pf->rq_list); + pf_request(); + spin_unlock_irq(&pf_spin_lock); + + return BLK_STS_OK; +} + +static int pf_next_buf(void) +{ + unsigned long saved_flags; + + pf_count--; + pf_run--; + pf_buf += 512; + pf_block++; + if (!pf_run) + return 1; + if (!pf_count) { + spin_lock_irqsave(&pf_spin_lock, saved_flags); + pf_end_request(0); + spin_unlock_irqrestore(&pf_spin_lock, saved_flags); + if (!pf_req) + return 1; + pf_count = blk_rq_cur_sectors(pf_req); + pf_buf = bio_data(pf_req->bio); + } + return 0; +} + +static inline void next_request(blk_status_t err) +{ + unsigned long saved_flags; + + spin_lock_irqsave(&pf_spin_lock, saved_flags); + pf_end_request(err); + pf_busy = 0; + pf_request(); + spin_unlock_irqrestore(&pf_spin_lock, saved_flags); +} + +/* detach from the calling context - in case the spinlock is held */ +static void do_pf_read(void) +{ + ps_set_intr(do_pf_read_start, NULL, 0, nice); +} + +static void do_pf_read_start(void) +{ + pf_busy = 1; + + if (pf_start(pf_current, ATAPI_READ_10, pf_block, pf_run)) { + pi_disconnect(pf_current->pi); + if (pf_retries < PF_MAX_RETRIES) { + pf_retries++; + pi_do_claimed(pf_current->pi, do_pf_read_start); + return; + } + next_request(BLK_STS_IOERR); + return; + } + pf_mask = STAT_DRQ; + ps_set_intr(do_pf_read_drq, pf_ready, PF_TMO, nice); +} + +static void do_pf_read_drq(void) +{ + while (1) { + if (pf_wait(pf_current, STAT_BUSY, STAT_DRQ | STAT_ERR, + "read block", "completion") & STAT_ERR) { + pi_disconnect(pf_current->pi); + if (pf_retries < PF_MAX_RETRIES) { + pf_req_sense(pf_current, 0); + pf_retries++; + pi_do_claimed(pf_current->pi, do_pf_read_start); + return; + } + next_request(BLK_STS_IOERR); + return; + } + pi_read_block(pf_current->pi, pf_buf, 512); + if (pf_next_buf()) + break; + } + pi_disconnect(pf_current->pi); + next_request(0); +} + +static void do_pf_write(void) +{ + ps_set_intr(do_pf_write_start, NULL, 0, nice); +} + +static void do_pf_write_start(void) +{ + pf_busy = 1; + + if (pf_start(pf_current, ATAPI_WRITE_10, pf_block, pf_run)) { + pi_disconnect(pf_current->pi); + if (pf_retries < PF_MAX_RETRIES) { + pf_retries++; + pi_do_claimed(pf_current->pi, do_pf_write_start); + return; + } + next_request(BLK_STS_IOERR); + return; + } + + while (1) { + if (pf_wait(pf_current, STAT_BUSY, STAT_DRQ | STAT_ERR, + "write block", "data wait") & STAT_ERR) { + pi_disconnect(pf_current->pi); + if (pf_retries < PF_MAX_RETRIES) { + pf_retries++; + pi_do_claimed(pf_current->pi, do_pf_write_start); + return; + } + next_request(BLK_STS_IOERR); + return; + } + pi_write_block(pf_current->pi, pf_buf, 512); + if (pf_next_buf()) + break; + } + pf_mask = 0; + ps_set_intr(do_pf_write_done, pf_ready, PF_TMO, nice); +} + +static void do_pf_write_done(void) +{ + if (pf_wait(pf_current, STAT_BUSY, 0, "write block", "done") & STAT_ERR) { + pi_disconnect(pf_current->pi); + if (pf_retries < PF_MAX_RETRIES) { + pf_retries++; + pi_do_claimed(pf_current->pi, do_pf_write_start); + return; + } + next_request(BLK_STS_IOERR); + return; + } + pi_disconnect(pf_current->pi); + next_request(0); +} + +static int __init pf_init(void) +{ /* preliminary initialisation */ + struct pf_unit *pf; + int unit; + + if (disable) + return -EINVAL; + + pf_init_units(); + + if (pf_detect()) + return -ENODEV; + pf_busy = 0; + + if (register_blkdev(major, name)) { + for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) { + if (!pf->disk) + continue; + blk_cleanup_queue(pf->disk->queue); + blk_mq_free_tag_set(&pf->tag_set); + put_disk(pf->disk); + } + return -EBUSY; + } + + for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) { + struct gendisk *disk = pf->disk; + + if (!pf->present) + continue; + disk->private_data = pf; + add_disk(disk); + } + return 0; +} + +static void __exit pf_exit(void) +{ + struct pf_unit *pf; + int unit; + unregister_blkdev(major, name); + for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) { + if (!pf->disk) + continue; + + if (pf->present) + del_gendisk(pf->disk); + + blk_cleanup_queue(pf->disk->queue); + blk_mq_free_tag_set(&pf->tag_set); + put_disk(pf->disk); + + if (pf->present) + pi_release(pf->pi); + } +} + +MODULE_LICENSE("GPL"); +module_init(pf_init) +module_exit(pf_exit) |