[S390] cio: Introduce separate files for channel-path related code.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

1 files changed, 433 insertions, 0 deletions

diff --git a/drivers/s390/cio/chp.c b/drivers/s390/cio/chp.c
new file mode 100644
index 000000000000..6e04521accd8
--- /dev/null
+++ b/drivers/s390/cio/chp.c
@@ -0,0 +1,433 @@
+/*
+ *  drivers/s390/cio/chp.c
+ *
+ *    Copyright IBM Corp. 1999,2007
+ *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
+ *               Arnd Bergmann (arndb@de.ibm.com)
+ *               Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
+ */
+
+#include <linux/bug.h>
+#include <linux/workqueue.h>
+#include <linux/spinlock.h>
+#include <asm/errno.h>
+
+#include "chpid.h"
+#include "cio.h"
+#include "css.h"
+#include "ioasm.h"
+#include "cio_debug.h"
+#include "chp.h"
+
+#define to_channelpath(device) container_of(device, struct channel_path, dev)
+
+/* Return channel_path struct for given chpid. */
+static inline struct channel_path *chpid_to_chp(struct chp_id chpid)
+{
+        return css[chpid.cssid]->chps[chpid.id];
+}
+
+/* Set vary state for given chpid. */
+static void set_chp_logically_online(struct chp_id chpid, int onoff)
+{
+        chpid_to_chp(chpid)->state = onoff;
+}
+
+/* On succes return 0 if channel-path is varied offline, 1 if it is varied
+ * online. Return -ENODEV if channel-path is not registered. */
+int chp_get_status(struct chp_id chpid)
+{
+        return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
+}
+
+/**
+ * chp_get_sch_opm - return opm for subchannel
+ * @sch: subchannel
+ *
+ * Calculate and return the operational path mask (opm) based on the chpids
+ * used by the subchannel and the status of the associated channel-paths.
+ */
+u8 chp_get_sch_opm(struct subchannel *sch)
+{
+        struct chp_id chpid;
+        int opm;
+        int i;
+
+        opm = 0;
+        chp_id_init(&chpid);
+        for (i=0; i < 8; i++) {
+                opm <<= 1;
+                chpid.id = sch->schib.pmcw.chpid[i];
+                if (chp_get_status(chpid) != 0)
+                        opm |= 1;
+        }
+        return opm;
+}
+
+/**
+ * chp_is_registered - check if a channel-path is registered
+ * @chpid: channel-path ID
+ *
+ * Return non-zero if a channel-path with the given chpid is registered,
+ * zero otherwise.
+ */
+int chp_is_registered(struct chp_id chpid)
+{
+        return chpid_to_chp(chpid) != NULL;
+}
+
+/*
+ * Function: s390_vary_chpid
+ * Varies the specified chpid online or offline
+ */
+static int s390_vary_chpid(struct chp_id chpid, int on)
+{
+        char dbf_text[15];
+        int status;
+
+        sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
+                chpid.id);
+        CIO_TRACE_EVENT( 2, dbf_text);
+
+        status = chp_get_status(chpid);
+        if (status < 0) {
+                printk(KERN_ERR "Can't vary unknown chpid %x.%02x\n",
+                       chpid.cssid, chpid.id);
+                return -EINVAL;
+        }
+
+        if (!on && !status) {
+                printk(KERN_ERR "chpid %x.%02x is already offline\n",
+                       chpid.cssid, chpid.id);
+                return -EINVAL;
+        }
+
+        set_chp_logically_online(chpid, on);
+        chsc_chp_vary(chpid, on);
+        return 0;
+}
+
+/*
+ * Channel measurement related functions
+ */
+static ssize_t chp_measurement_chars_read(struct kobject *kobj, char *buf,
+                                          loff_t off, size_t count)
+{
+        struct channel_path *chp;
+        unsigned int size;
+
+        chp = to_channelpath(container_of(kobj, struct device, kobj));
+        if (!chp->cmg_chars)
+                return 0;
+
+        size = sizeof(struct cmg_chars);
+
+        if (off > size)
+                return 0;
+        if (off + count > size)
+                count = size - off;
+        memcpy(buf, chp->cmg_chars + off, count);
+        return count;
+}
+
+static struct bin_attribute chp_measurement_chars_attr = {
+        .attr = {
+                .name = "measurement_chars",
+                .mode = S_IRUSR,
+                .owner = THIS_MODULE,
+        },
+        .size = sizeof(struct cmg_chars),
+        .read = chp_measurement_chars_read,
+};
+
+static void chp_measurement_copy_block(struct cmg_entry *buf,
+                                       struct channel_subsystem *css,
+                                       struct chp_id chpid)
+{
+        void *area;
+        struct cmg_entry *entry, reference_buf;
+        int idx;
+
+        if (chpid.id < 128) {
+                area = css->cub_addr1;
+                idx = chpid.id;
+        } else {
+                area = css->cub_addr2;
+                idx = chpid.id - 128;
+        }
+        entry = area + (idx * sizeof(struct cmg_entry));
+        do {
+                memcpy(buf, entry, sizeof(*entry));
+                memcpy(&reference_buf, entry, sizeof(*entry));
+        } while (reference_buf.values[0] != buf->values[0]);
+}
+
+static ssize_t chp_measurement_read(struct kobject *kobj, char *buf,
+                                    loff_t off, size_t count)
+{
+        struct channel_path *chp;
+        struct channel_subsystem *css;
+        unsigned int size;
+
+        chp = to_channelpath(container_of(kobj, struct device, kobj));
+        css = to_css(chp->dev.parent);
+
+        size = sizeof(struct cmg_entry);
+
+        /* Only allow single reads. */
+        if (off || count < size)
+                return 0;
+        chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
+        count = size;
+        return count;
+}
+
+static struct bin_attribute chp_measurement_attr = {
+        .attr = {
+                .name = "measurement",
+                .mode = S_IRUSR,
+                .owner = THIS_MODULE,
+        },
+        .size = sizeof(struct cmg_entry),
+        .read = chp_measurement_read,
+};
+
+void chp_remove_cmg_attr(struct channel_path *chp)
+{
+        device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
+        device_remove_bin_file(&chp->dev, &chp_measurement_attr);
+}
+
+int chp_add_cmg_attr(struct channel_path *chp)
+{
+        int ret;
+
+        ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
+        if (ret)
+                return ret;
+        ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
+        if (ret)
+                device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
+        return ret;
+}
+
+/*
+ * Files for the channel path entries.
+ */
+static ssize_t chp_status_show(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+        struct channel_path *chp = container_of(dev, struct channel_path, dev);
+
+        if (!chp)
+                return 0;
+        return (chp_get_status(chp->chpid) ? sprintf(buf, "online\n") :
+                sprintf(buf, "offline\n"));
+}
+
+static ssize_t chp_status_write(struct device *dev,
+                                struct device_attribute *attr,
+                                const char *buf, size_t count)
+{
+        struct channel_path *cp = container_of(dev, struct channel_path, dev);
+        char cmd[10];
+        int num_args;
+        int error;
+
+        num_args = sscanf(buf, "%5s", cmd);
+        if (!num_args)
+                return count;
+
+        if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1"))
+                error = s390_vary_chpid(cp->chpid, 1);
+        else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0"))
+                error = s390_vary_chpid(cp->chpid, 0);
+        else
+                error = -EINVAL;
+
+        return error < 0 ? error : count;
+
+}
+
+static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
+
+static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
+                             char *buf)
+{
+        struct channel_path *chp = container_of(dev, struct channel_path, dev);
+
+        if (!chp)
+                return 0;
+        return sprintf(buf, "%x\n", chp->desc.desc);
+}
+
+static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
+
+static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+        struct channel_path *chp = to_channelpath(dev);
+
+        if (!chp)
+                return 0;
+        if (chp->cmg == -1) /* channel measurements not available */
+                return sprintf(buf, "unknown\n");
+        return sprintf(buf, "%x\n", chp->cmg);
+}
+
+static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
+
+static ssize_t chp_shared_show(struct device *dev,
+                               struct device_attribute *attr, char *buf)
+{
+        struct channel_path *chp = to_channelpath(dev);
+
+        if (!chp)
+                return 0;
+        if (chp->shared == -1) /* channel measurements not available */
+                return sprintf(buf, "unknown\n");
+        return sprintf(buf, "%x\n", chp->shared);
+}
+
+static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
+
+static struct attribute * chp_attrs[] = {
+        &dev_attr_status.attr,
+        &dev_attr_type.attr,
+        &dev_attr_cmg.attr,
+        &dev_attr_shared.attr,
+        NULL,
+};
+
+static struct attribute_group chp_attr_group = {
+        .attrs = chp_attrs,
+};
+
+static void chp_release(struct device *dev)
+{
+        struct channel_path *cp;
+
+        cp = container_of(dev, struct channel_path, dev);
+        kfree(cp);
+}
+
+/**
+ * chp_new - register a new channel-path
+ * @chpid - channel-path ID
+ *
+ * Create and register data structure representing new channel-path. Return
+ * zero on success, non-zero otherwise.
+ */
+int chp_new(struct chp_id chpid)
+{
+        struct channel_path *chp;
+        int ret;
+
+        chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
+        if (!chp)
+                return -ENOMEM;
+
+        /* fill in status, etc. */
+        chp->chpid = chpid;
+        chp->state = 1;
+        chp->dev.parent = &css[chpid.cssid]->device;
+        chp->dev.release = chp_release;
+        snprintf(chp->dev.bus_id, BUS_ID_SIZE, "chp%x.%02x", chpid.cssid,
+                 chpid.id);
+
+        /* Obtain channel path description and fill it in. */
+        ret = chsc_determine_channel_path_description(chpid, &chp->desc);
+        if (ret)
+                goto out_free;
+        /* Get channel-measurement characteristics. */
+        if (css_characteristics_avail && css_chsc_characteristics.scmc
+            && css_chsc_characteristics.secm) {
+                ret = chsc_get_channel_measurement_chars(chp);
+                if (ret)
+                        goto out_free;
+        } else {
+                static int msg_done;
+
+                if (!msg_done) {
+                        printk(KERN_WARNING "cio: Channel measurements not "
+                               "available, continuing.\n");
+                        msg_done = 1;
+                }
+                chp->cmg = -1;
+        }
+
+        /* make it known to the system */
+        ret = device_register(&chp->dev);
+        if (ret) {
+                printk(KERN_WARNING "%s: could not register %x.%02x\n",
+                       __func__, chpid.cssid, chpid.id);
+                goto out_free;
+        }
+        ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
+        if (ret) {
+                device_unregister(&chp->dev);
+                goto out_free;
+        }
+        mutex_lock(&css[chpid.cssid]->mutex);
+        if (css[chpid.cssid]->cm_enabled) {
+                ret = chp_add_cmg_attr(chp);
+                if (ret) {
+                        sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
+                        device_unregister(&chp->dev);
+                        mutex_unlock(&css[chpid.cssid]->mutex);
+                        goto out_free;
+                }
+        }
+        css[chpid.cssid]->chps[chpid.id] = chp;
+        mutex_unlock(&css[chpid.cssid]->mutex);
+        return ret;
+out_free:
+        kfree(chp);
+        return ret;
+}
+
+/**
+ * chp_get_chp_desc - return newly allocated channel-path description
+ * @chpid: channel-path ID
+ *
+ * On success return a newly allocated copy of the channel-path description
+ * data associated with the given channel-path ID. Return %NULL on error.
+ */
+void *chp_get_chp_desc(struct chp_id chpid)
+{
+        struct channel_path *chp;
+        struct channel_path_desc *desc;
+
+        chp = chpid_to_chp(chpid);
+        if (!chp)
+                return NULL;
+        desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
+        if (!desc)
+                return NULL;
+        memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
+        return desc;
+}
+
+/**
+ * chp_process_crw - process channel-path status change
+ * @id: channel-path ID number
+ * @status: non-zero if channel-path has become available, zero otherwise
+ *
+ * Handle channel-report-words indicating that the status of a channel-path
+ * has changed.
+ */
+int chp_process_crw(int id, int status)
+{
+        struct chp_id chpid;
+
+        chp_id_init(&chpid);
+        chpid.id = id;
+        if (status) {
+                if (!chp_is_registered(chpid))
+                        chp_new(chpid);
+                return chsc_chp_online(chpid);
+        } else {
+                chsc_chp_offline(chpid);
+                return 0;
+        }
+}