[PATCH v4 1/5] s390/ap: Externalize AP bus specific bitmap reading function

From: Jason J. Herne
Date: Tue Mar 26 2024 - 12:47:40 EST


Rename hex2bitmap() to ap_hex2bitmap() and export it for external
use. This function will be used by the implementation of the vfio-ap
ap_config sysfs attribute.

Signed-off-by: Jason J. Herne <jjherne@xxxxxxxxxxxxx>
Reviewed-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
Reviewed-by: Harald Freudenberger <freude@xxxxxxxxxxxxx>
---
drivers/s390/crypto/ap_bus.c | 13 +++----------
drivers/s390/crypto/ap_bus.h | 22 ++++++++++++++++++++++
2 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index cce0bafd4c92..1be07197eda3 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -1068,15 +1068,7 @@ void ap_bus_cfg_chg(void)
ap_bus_force_rescan();
}

-/*
- * hex2bitmap() - parse hex mask string and set bitmap.
- * Valid strings are "0x012345678" with at least one valid hex number.
- * Rest of the bitmap to the right is padded with 0. No spaces allowed
- * within the string, the leading 0x may be omitted.
- * Returns the bitmask with exactly the bits set as given by the hex
- * string (both in big endian order).
- */
-static int hex2bitmap(const char *str, unsigned long *bitmap, int bits)
+int ap_hex2bitmap(const char *str, unsigned long *bitmap, int bits)
{
int i, n, b;

@@ -1103,6 +1095,7 @@ static int hex2bitmap(const char *str, unsigned long *bitmap, int bits)
return -EINVAL;
return 0;
}
+EXPORT_SYMBOL(ap_hex2bitmap);

/*
* modify_bitmap() - parse bitmask argument and modify an existing
@@ -1168,7 +1161,7 @@ static int ap_parse_bitmap_str(const char *str, unsigned long *bitmap, int bits,
rc = modify_bitmap(str, newmap, bits);
} else {
memset(newmap, 0, size);
- rc = hex2bitmap(str, newmap, bits);
+ rc = ap_hex2bitmap(str, newmap, bits);
}
return rc;
}
diff --git a/drivers/s390/crypto/ap_bus.h b/drivers/s390/crypto/ap_bus.h
index 59c7ed49aa02..1db9597509da 100644
--- a/drivers/s390/crypto/ap_bus.h
+++ b/drivers/s390/crypto/ap_bus.h
@@ -343,6 +343,28 @@ int ap_parse_mask_str(const char *str,
unsigned long *bitmap, int bits,
struct mutex *lock);

+/*
+ * ap_hex2bitmap() - Convert a string containing a hexadecimal number (str)
+ * into a bitmap (bitmap) with bits set that correspond to the bits represented
+ * by the hex string. Input and output data is in big endian order.
+ *
+ * str - Input hex string of format "0x1234abcd". The leading "0x" is optional.
+ * At least one digit is required. Must be large enough to hold the number of
+ * bits represented by the bits parameter.
+ *
+ * bitmap - Pointer to a bitmap. Upon successful completion of this function,
+ * this bitmap will have bits set to match the value of str. If bitmap is longer
+ * than str, then the rightmost bits of bitmap are padded with zeros. Must be
+ * large enough to hold the number of bits represented by the bits parameter.
+ *
+ * bits - Length, in bits, of the bitmap represented by str. Must be a multiple
+ * of 8.
+ *
+ * Returns: 0 on success
+ * -EINVAL If str format is invalid or bits is not a multiple of 8.
+ */
+int ap_hex2bitmap(const char *str, unsigned long *bitmap, int bits);
+
/*
* Interface to wait for the AP bus to have done one initial ap bus
* scan and all detected APQNs have been bound to device drivers.
--
2.41.0