[S390] cio: provide functions for fcx enabled I/O
Provide functions for assembling and starting fcx enabled I/O request
blocks.
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>
diff --git a/drivers/s390/cio/fcx.c b/drivers/s390/cio/fcx.c
new file mode 100644
index 0000000..61677df
--- /dev/null
+++ b/drivers/s390/cio/fcx.c
@@ -0,0 +1,350 @@
+/*
+ * Functions for assembling fcx enabled I/O control blocks.
+ *
+ * Copyright IBM Corp. 2008
+ * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <asm/fcx.h>
+#include "cio.h"
+
+/**
+ * tcw_get_intrg - return pointer to associated interrogate tcw
+ * @tcw: pointer to the original tcw
+ *
+ * Return a pointer to the interrogate tcw associated with the specified tcw
+ * or %NULL if there is no associated interrogate tcw.
+ */
+struct tcw *tcw_get_intrg(struct tcw *tcw)
+{
+ return (struct tcw *) ((addr_t) tcw->intrg);
+}
+EXPORT_SYMBOL(tcw_get_intrg);
+
+/**
+ * tcw_get_data - return pointer to input/output data associated with tcw
+ * @tcw: pointer to the tcw
+ *
+ * Return the input or output data address specified in the tcw depending
+ * on whether the r-bit or the w-bit is set. If neither bit is set, return
+ * %NULL.
+ */
+void *tcw_get_data(struct tcw *tcw)
+{
+ if (tcw->r)
+ return (void *) ((addr_t) tcw->input);
+ if (tcw->w)
+ return (void *) ((addr_t) tcw->output);
+ return NULL;
+}
+EXPORT_SYMBOL(tcw_get_data);
+
+/**
+ * tcw_get_tccb - return pointer to tccb associated with tcw
+ * @tcw: pointer to the tcw
+ *
+ * Return pointer to the tccb associated with this tcw.
+ */
+struct tccb *tcw_get_tccb(struct tcw *tcw)
+{
+ return (struct tccb *) ((addr_t) tcw->tccb);
+}
+EXPORT_SYMBOL(tcw_get_tccb);
+
+/**
+ * tcw_get_tsb - return pointer to tsb associated with tcw
+ * @tcw: pointer to the tcw
+ *
+ * Return pointer to the tsb associated with this tcw.
+ */
+struct tsb *tcw_get_tsb(struct tcw *tcw)
+{
+ return (struct tsb *) ((addr_t) tcw->tsb);
+}
+EXPORT_SYMBOL(tcw_get_tsb);
+
+/**
+ * tcw_init - initialize tcw data structure
+ * @tcw: pointer to the tcw to be initialized
+ * @r: initial value of the r-bit
+ * @w: initial value of the w-bit
+ *
+ * Initialize all fields of the specified tcw data structure with zero and
+ * fill in the format, flags, r and w fields.
+ */
+void tcw_init(struct tcw *tcw, int r, int w)
+{
+ memset(tcw, 0, sizeof(struct tcw));
+ tcw->format = TCW_FORMAT_DEFAULT;
+ tcw->flags = TCW_FLAGS_TIDAW_FORMAT(TCW_TIDAW_FORMAT_DEFAULT);
+ if (r)
+ tcw->r = 1;
+ if (w)
+ tcw->w = 1;
+}
+EXPORT_SYMBOL(tcw_init);
+
+static inline size_t tca_size(struct tccb *tccb)
+{
+ return tccb->tcah.tcal - 12;
+}
+
+static u32 calc_dcw_count(struct tccb *tccb)
+{
+ int offset;
+ struct dcw *dcw;
+ u32 count = 0;
+ size_t size;
+
+ size = tca_size(tccb);
+ for (offset = 0; offset < size;) {
+ dcw = (struct dcw *) &tccb->tca[offset];
+ count += dcw->count;
+ if (!(dcw->flags & DCW_FLAGS_CC))
+ break;
+ offset += sizeof(struct dcw) + ALIGN((int) dcw->cd_count, 4);
+ }
+ return count;
+}
+
+static u32 calc_cbc_size(struct tidaw *tidaw, int num)
+{
+ int i;
+ u32 cbc_data;
+ u32 cbc_count = 0;
+ u64 data_count = 0;
+
+ for (i = 0; i < num; i++) {
+ if (tidaw[i].flags & TIDAW_FLAGS_LAST)
+ break;
+ /* TODO: find out if padding applies to total of data
+ * transferred or data transferred by this tidaw. Assumption:
+ * applies to total. */
+ data_count += tidaw[i].count;
+ if (tidaw[i].flags & TIDAW_FLAGS_INSERT_CBC) {
+ cbc_data = 4 + ALIGN(data_count, 4) - data_count;
+ cbc_count += cbc_data;
+ data_count += cbc_data;
+ }
+ }
+ return cbc_count;
+}
+
+/**
+ * tcw_finalize - finalize tcw length fields and tidaw list
+ * @tcw: pointer to the tcw
+ * @num_tidaws: the number of tidaws used to address input/output data or zero
+ * if no tida is used
+ *
+ * Calculate the input-/output-count and tccbl field in the tcw, add a
+ * tcat the tccb and terminate the data tidaw list if used.
+ *
+ * Note: in case input- or output-tida is used, the tidaw-list must be stored
+ * in contiguous storage (no ttic). The tcal field in the tccb must be
+ * up-to-date.
+ */
+void tcw_finalize(struct tcw *tcw, int num_tidaws)
+{
+ struct tidaw *tidaw;
+ struct tccb *tccb;
+ struct tccb_tcat *tcat;
+ u32 count;
+
+ /* Terminate tidaw list. */
+ tidaw = tcw_get_data(tcw);
+ if (num_tidaws > 0)
+ tidaw[num_tidaws - 1].flags |= TIDAW_FLAGS_LAST;
+ /* Add tcat to tccb. */
+ tccb = tcw_get_tccb(tcw);
+ tcat = (struct tccb_tcat *) &tccb->tca[tca_size(tccb)];
+ memset(tcat, 0, sizeof(tcat));
+ /* Calculate tcw input/output count and tcat transport count. */
+ count = calc_dcw_count(tccb);
+ if (tcw->w && (tcw->flags & TCW_FLAGS_OUTPUT_TIDA))
+ count += calc_cbc_size(tidaw, num_tidaws);
+ if (tcw->r)
+ tcw->input_count = count;
+ else if (tcw->w)
+ tcw->output_count = count;
+ tcat->count = ALIGN(count, 4) + 4;
+ /* Calculate tccbl. */
+ tcw->tccbl = (sizeof(struct tccb) + tca_size(tccb) +
+ sizeof(struct tccb_tcat) - 20) >> 2;
+}
+EXPORT_SYMBOL(tcw_finalize);
+
+/**
+ * tcw_set_intrg - set the interrogate tcw address of a tcw
+ * @tcw: the tcw address
+ * @intrg_tcw: the address of the interrogate tcw
+ *
+ * Set the address of the interrogate tcw in the specified tcw.
+ */
+void tcw_set_intrg(struct tcw *tcw, struct tcw *intrg_tcw)
+{
+ tcw->intrg = (u32) ((addr_t) intrg_tcw);
+}
+EXPORT_SYMBOL(tcw_set_intrg);
+
+/**
+ * tcw_set_data - set data address and tida flag of a tcw
+ * @tcw: the tcw address
+ * @data: the data address
+ * @use_tidal: zero of the data address specifies a contiguous block of data,
+ * non-zero if it specifies a list if tidaws.
+ *
+ * Set the input/output data address of a tcw (depending on the value of the
+ * r-flag and w-flag). If @use_tidal is non-zero, the corresponding tida flag
+ * is set as well.
+ */
+void tcw_set_data(struct tcw *tcw, void *data, int use_tidal)
+{
+ if (tcw->r) {
+ tcw->input = (u64) ((addr_t) data);
+ if (use_tidal)
+ tcw->flags |= TCW_FLAGS_INPUT_TIDA;
+ } else if (tcw->w) {
+ tcw->output = (u64) ((addr_t) data);
+ if (use_tidal)
+ tcw->flags |= TCW_FLAGS_OUTPUT_TIDA;
+ }
+}
+EXPORT_SYMBOL(tcw_set_data);
+
+/**
+ * tcw_set_tccb - set tccb address of a tcw
+ * @tcw: the tcw address
+ * @tccb: the tccb address
+ *
+ * Set the address of the tccb in the specified tcw.
+ */
+void tcw_set_tccb(struct tcw *tcw, struct tccb *tccb)
+{
+ tcw->tccb = (u64) ((addr_t) tccb);
+}
+EXPORT_SYMBOL(tcw_set_tccb);
+
+/**
+ * tcw_set_tsb - set tsb address of a tcw
+ * @tcw: the tcw address
+ * @tsb: the tsb address
+ *
+ * Set the address of the tsb in the specified tcw.
+ */
+void tcw_set_tsb(struct tcw *tcw, struct tsb *tsb)
+{
+ tcw->tsb = (u64) ((addr_t) tsb);
+}
+EXPORT_SYMBOL(tcw_set_tsb);
+
+/**
+ * tccb_init - initialize tccb
+ * @tccb: the tccb address
+ * @size: the maximum size of the tccb
+ * @sac: the service-action-code to be user
+ *
+ * Initialize the header of the specified tccb by resetting all values to zero
+ * and filling in defaults for format, sac and initial tcal fields.
+ */
+void tccb_init(struct tccb *tccb, size_t size, u32 sac)
+{
+ memset(tccb, 0, size);
+ tccb->tcah.format = TCCB_FORMAT_DEFAULT;
+ tccb->tcah.sac = sac;
+ tccb->tcah.tcal = 12;
+}
+EXPORT_SYMBOL(tccb_init);
+
+/**
+ * tsb_init - initialize tsb
+ * @tsb: the tsb address
+ *
+ * Initialize the specified tsb by resetting all values to zero.
+ */
+void tsb_init(struct tsb *tsb)
+{
+ memset(tsb, 0, sizeof(tsb));
+}
+EXPORT_SYMBOL(tsb_init);
+
+/**
+ * tccb_add_dcw - add a dcw to the tccb
+ * @tccb: the tccb address
+ * @tccb_size: the maximum tccb size
+ * @cmd: the dcw command
+ * @flags: flags for the dcw
+ * @cd: pointer to control data for this dcw or NULL if none is required
+ * @cd_count: number of control data bytes for this dcw
+ * @count: number of data bytes for this dcw
+ *
+ * Add a new dcw to the specified tccb by writing the dcw information specified
+ * by @cmd, @flags, @cd, @cd_count and @count to the tca of the tccb. Return
+ * a pointer to the newly added dcw on success or -%ENOSPC if the new dcw
+ * would exceed the available space as defined by @tccb_size.
+ *
+ * Note: the tcal field of the tccb header will be updates to reflect added
+ * content.
+ */
+struct dcw *tccb_add_dcw(struct tccb *tccb, size_t tccb_size, u8 cmd, u8 flags,
+ void *cd, u8 cd_count, u32 count)
+{
+ struct dcw *dcw;
+ int size;
+ int tca_offset;
+
+ /* Check for space. */
+ tca_offset = tca_size(tccb);
+ size = ALIGN(sizeof(struct dcw) + cd_count, 4);
+ if (sizeof(struct tccb_tcah) + tca_offset + size +
+ sizeof(struct tccb_tcat) > tccb_size)
+ return ERR_PTR(-ENOSPC);
+ /* Add dcw to tca. */
+ dcw = (struct dcw *) &tccb->tca[tca_offset];
+ memset(dcw, 0, size);
+ dcw->cmd = cmd;
+ dcw->flags = flags;
+ dcw->count = count;
+ dcw->cd_count = cd_count;
+ if (cd)
+ memcpy(&dcw->cd[0], cd, cd_count);
+ tccb->tcah.tcal += size;
+ return dcw;
+}
+EXPORT_SYMBOL(tccb_add_dcw);
+
+/**
+ * tcw_add_tidaw - add a tidaw to a tcw
+ * @tcw: the tcw address
+ * @num_tidaws: the current number of tidaws
+ * @flags: flags for the new tidaw
+ * @addr: address value for the new tidaw
+ * @count: count value for the new tidaw
+ *
+ * Add a new tidaw to the input/output data tidaw-list of the specified tcw
+ * (depending on the value of the r-flag and w-flag) and return a pointer to
+ * the new tidaw.
+ *
+ * Note: the tidaw-list is assumed to be contiguous with no ttics. The caller
+ * must ensure that there is enough space for the new tidaw. The last-tidaw
+ * flag for the last tidaw in the list will be set by tcw_finalize.
+ */
+struct tidaw *tcw_add_tidaw(struct tcw *tcw, int num_tidaws, u8 flags,
+ void *addr, u32 count)
+{
+ struct tidaw *tidaw;
+
+ /* Add tidaw to tidaw-list. */
+ tidaw = ((struct tidaw *) tcw_get_data(tcw)) + num_tidaws;
+ memset(tidaw, 0, sizeof(struct tidaw));
+ tidaw->flags = flags;
+ tidaw->count = count;
+ tidaw->addr = (u64) ((addr_t) addr);
+ return tidaw;
+}
+EXPORT_SYMBOL(tcw_add_tidaw);