From: Tejun Heo Date: Sun, 5 Mar 2006 08:55:58 +0000 (+0900) Subject: [PATCH] libata: implement ata_dev_revalidate() X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=623a3128aa2b86caa8e06e762e9e444177e4fa47;p=linux-beck.git [PATCH] libata: implement ata_dev_revalidate() ata_dev_revalidate() re-reads IDENTIFY PAGE of the given device and makes sure it's the same device as the configured one. Once it's verified that it's the same device, @dev is configured according to newly read IDENTIFY PAGE. Note that revalidation currently doesn't invoke transfer mode reconfiguration. Criteria for 'same device' * same class (of course) * same model string * same serial string * if ATA, same n_sectors (to catch geometry parameter changes) Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index d65aa86ddbb2..5d0adfa4610a 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -2345,6 +2345,120 @@ int ata_drive_probe_reset(struct ata_port *ap, ata_probeinit_fn_t probeinit, return rc; } +/** + * ata_dev_same_device - Determine whether new ID matches configured device + * @ap: port on which the device to compare against resides + * @dev: device to compare against + * @new_class: class of the new device + * @new_id: IDENTIFY page of the new device + * + * Compare @new_class and @new_id against @dev and determine + * whether @dev is the device indicated by @new_class and + * @new_id. + * + * LOCKING: + * None. + * + * RETURNS: + * 1 if @dev matches @new_class and @new_id, 0 otherwise. + */ +static int ata_dev_same_device(struct ata_port *ap, struct ata_device *dev, + unsigned int new_class, const u16 *new_id) +{ + const u16 *old_id = dev->id; + unsigned char model[2][41], serial[2][21]; + u64 new_n_sectors; + + if (dev->class != new_class) { + printk(KERN_INFO + "ata%u: dev %u class mismatch %d != %d\n", + ap->id, dev->devno, dev->class, new_class); + return 0; + } + + ata_id_c_string(old_id, model[0], ATA_ID_PROD_OFS, sizeof(model[0])); + ata_id_c_string(new_id, model[1], ATA_ID_PROD_OFS, sizeof(model[1])); + ata_id_c_string(old_id, serial[0], ATA_ID_SERNO_OFS, sizeof(serial[0])); + ata_id_c_string(new_id, serial[1], ATA_ID_SERNO_OFS, sizeof(serial[1])); + new_n_sectors = ata_id_n_sectors(new_id); + + if (strcmp(model[0], model[1])) { + printk(KERN_INFO + "ata%u: dev %u model number mismatch '%s' != '%s'\n", + ap->id, dev->devno, model[0], model[1]); + return 0; + } + + if (strcmp(serial[0], serial[1])) { + printk(KERN_INFO + "ata%u: dev %u serial number mismatch '%s' != '%s'\n", + ap->id, dev->devno, serial[0], serial[1]); + return 0; + } + + if (dev->class == ATA_DEV_ATA && dev->n_sectors != new_n_sectors) { + printk(KERN_INFO + "ata%u: dev %u n_sectors mismatch %llu != %llu\n", + ap->id, dev->devno, (unsigned long long)dev->n_sectors, + (unsigned long long)new_n_sectors); + return 0; + } + + return 1; +} + +/** + * ata_dev_revalidate - Revalidate ATA device + * @ap: port on which the device to revalidate resides + * @dev: device to revalidate + * @post_reset: is this revalidation after reset? + * + * Re-read IDENTIFY page and make sure @dev is still attached to + * the port. + * + * LOCKING: + * Kernel thread context (may sleep) + * + * RETURNS: + * 0 on success, negative errno otherwise + */ +int ata_dev_revalidate(struct ata_port *ap, struct ata_device *dev, + int post_reset) +{ + unsigned int class; + u16 *id; + int rc; + + if (!ata_dev_present(dev)) + return -ENODEV; + + class = dev->class; + id = NULL; + + /* allocate & read ID data */ + rc = ata_dev_read_id(ap, dev, &class, post_reset, &id); + if (rc) + goto fail; + + /* is the device still there? */ + if (!ata_dev_same_device(ap, dev, class, id)) { + rc = -ENODEV; + goto fail; + } + + kfree(dev->id); + dev->id = id; + + /* configure device according to the new ID */ + return ata_dev_configure(ap, dev, 0); + + fail: + printk(KERN_ERR "ata%u: dev %u revalidation failed (errno=%d)\n", + ap->id, dev->devno, rc); + kfree(id); + return rc; +} + static void ata_pr_blacklisted(const struct ata_port *ap, const struct ata_device *dev) { @@ -4964,6 +5078,7 @@ EXPORT_SYMBOL_GPL(sata_std_hardreset); EXPORT_SYMBOL_GPL(ata_std_postreset); EXPORT_SYMBOL_GPL(ata_std_probe_reset); EXPORT_SYMBOL_GPL(ata_drive_probe_reset); +EXPORT_SYMBOL_GPL(ata_dev_revalidate); EXPORT_SYMBOL_GPL(ata_port_disable); EXPORT_SYMBOL_GPL(ata_ratelimit); EXPORT_SYMBOL_GPL(ata_busy_sleep); diff --git a/include/linux/libata.h b/include/linux/libata.h index 86a504f0ef06..66dce58f1941 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -485,6 +485,8 @@ extern int ata_std_softreset(struct ata_port *ap, int verbose, extern int sata_std_hardreset(struct ata_port *ap, int verbose, unsigned int *class); extern void ata_std_postreset(struct ata_port *ap, unsigned int *classes); +extern int ata_dev_revalidate(struct ata_port *ap, struct ata_device *dev, + int post_reset); extern void ata_port_disable(struct ata_port *); extern void ata_std_ports(struct ata_ioports *ioaddr); #ifdef CONFIG_PCI