Sometimes it is desired to produce a single log line for errors.
Add a new helper function for such purpose.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/firmware/efi/cper.c | 59 +++++++++++++++++++++++++++++++++++++
include/linux/cper.h | 3 ++
2 files changed, 62 insertions(+)
diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c
index 7d2cdd9e2227..9bf27af3e870 100644
--- a/drivers/firmware/efi/cper.c
+++ b/drivers/firmware/efi/cper.c
@@ -106,6 +106,65 @@ void cper_print_bits(const char *pfx, unsigned int bits,
printk("%s\n", buf);
}
+/*
+ * cper_bits_to_str - return a string for set bits
+ * @buf: buffer to store the output string
+ * @buf_size: size of the output string buffer
+ * @bits: bit mask
+ * @strs: string array, indexed by bit position
+ * @strs_size: size of the string array: @strs
+ *
+ * add to @buf the bitmask in hexadecimal. Then, for each set bit in @bits,
+ * add the corresponding string in @strs to @buf.
+ */
+char *cper_bits_to_str(char *buf, int buf_size, unsigned int bits,
+ const char * const strs[], unsigned int strs_size,
+ unsigned int mask)
+{
+ int i, size, first_bit;
+ int len = buf_size;
+ const char *start;
+ char *str = buf;
+
+ if (strs_size < 16)
+ size = snprintf(str, len, "0x%02x: ", bits);
+ if (strs_size < 32)
+ size = snprintf(str, len, "0x%04x: ", bits);
+
+ len -= size;
+ str += size;
+
+ start = str;
+
+ if (mask) {
+ first_bit = ffs(mask) - 1;
+ if (bits & ~mask) {
+ size = strscpy(str, "reserved bit(s)", len);
+ len -= size;
+ str += size;
+ }
+ } else {
+ first_bit = 0;
+ }
+
+ for (i = 0; i < strs_size; i++) {
+ if (!(bits & (1U << (i + first_bit))))
+ continue;
+
+ if (*start && len > 0) {
+ *str = '|';
+ len--;
+ str++;
+ }
+
+ size = strscpy(str, strs[i], len);
+ len -= size;
+ str += size;
+ }
+ return buf;
+}
+EXPORT_SYMBOL_GPL(cper_bits_to_str);
+
static const char * const proc_type_strs[] = {
"IA32/X64",
"IA64",
diff --git a/include/linux/cper.h b/include/linux/cper.h
index 265b0f8fc0b3..856e8f00a7fb 100644
--- a/include/linux/cper.h
+++ b/include/linux/cper.h
@@ -584,6 +584,9 @@ const char *cper_mem_err_type_str(unsigned int);
const char *cper_mem_err_status_str(u64 status);
void cper_print_bits(const char *prefix, unsigned int bits,
const char * const strs[], unsigned int strs_size);
+char *cper_bits_to_str(char *buf, int buf_size, unsigned int bits,
+ const char * const strs[], unsigned int strs_size,
+ unsigned int mask);
void cper_mem_err_pack(const struct cper_sec_mem_err *,
struct cper_mem_err_compact *);
const char *cper_mem_err_unpack(struct trace_seq *,
--
2.45.2
