Add a drm printer suitable for use with the read callback for
devcoredump or any other file operation read() function that
isn't otherwise covered by seq_file.
Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_print.c | 54 +++++++++++++++++++++++++++++++++++++++++++++
include/drm/drm_print.h | 27 +++++++++++++++++++++++
2 files changed, 81 insertions(+)
diff --git a/drivers/gpu/drm/drm_print.c b/drivers/gpu/drm/drm_print.c
index 781518fd88e3..f6efde48f8b3 100644
--- a/drivers/gpu/drm/drm_print.c
+++ b/drivers/gpu/drm/drm_print.c
@@ -30,6 +30,60 @@
#include <drm/drmP.h>
#include <drm/drm_print.h>
+void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf)
+{
+ struct drm_print_iterator *iterator = p->arg;
+
+ ssize_t len;
+
+ if (!iterator->remain)
+ return;
+
+ if (iterator->offset < iterator->start) {
+ char *buf;
+ ssize_t copy;
+
+ /* Figure out how big the string will be */
+ len = snprintf(NULL, 0, "%pV", vaf);
+
+ if (iterator->offset + len <= iterator->start) {
+ iterator->offset += len;
+ return;
+ }
+
+ /* Print the string into a temporary buffer */
+ buf = kmalloc(len + 1,
+ GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY);
+ if (!buf)
+ return;
+
+ snprintf(buf, len + 1, "%pV", vaf);
+
+ copy = len - (iterator->start - iterator->offset);
+
+ if (copy > iterator->remain)
+ copy = iterator->remain;
+
+ /* Copy out the bit of the string that we need */
+ memcpy(iterator->data,
+ buf + (iterator->start - iterator->offset), copy);
+
+ iterator->offset = iterator->start + copy;
+ iterator->remain -= copy;
+
+ kfree(buf);
+ } else {
+ ssize_t pos = iterator->offset - iterator->start;
+
+ len = scnprintf(((char *) iterator->data) + pos,
+ iterator->remain, "%pV", vaf);
+
+ iterator->offset += len;
+ iterator->remain -= len;
+ }
+}
+EXPORT_SYMBOL(__drm_printfn_coredump);
+
void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf)
{
seq_printf(p->arg, "%pV", vaf);
diff --git a/include/drm/drm_print.h b/include/drm/drm_print.h
index 2a4a42e59a47..29eee5175eac 100644
--- a/include/drm/drm_print.h
+++ b/include/drm/drm_print.h
@@ -73,6 +73,7 @@ struct drm_printer {
const char *prefix;
};
+void __drm_printfn_coredump(struct drm_printer *p, struct va_format *vaf);
void __drm_printfn_seq_file(struct drm_printer *p, struct va_format *vaf);
void __drm_printfn_info(struct drm_printer *p, struct va_format *vaf);
void __drm_printfn_debug(struct drm_printer *p, struct va_format *vaf);
@@ -104,6 +105,32 @@ drm_vprintf(struct drm_printer *p, const char *fmt, va_list *va)
#define drm_printf_indent(printer, indent, fmt, ...) \
drm_printf((printer), "%.*s" fmt, (indent), "\t\t\t\t\tX", ##__VA_ARGS__)
+struct drm_print_iterator {
+ void *data;
+
+ ssize_t start;
+ ssize_t offset;
+ ssize_t remain;
+};
+
+/**
+ * drm_coredump_printer - construct a &drm_printer that can output to a buffer
+ * from the read function for devcoredump
+ * @iter: A pointer to a struct drm_print_iterator for the read instance
+ *
+ * RETURNS:
+ * The &drm_printer object
+ */
+static inline struct drm_printer
+drm_coredump_printer(struct drm_print_iterator *iter)
+{
+ struct drm_printer p = {
+ .printfn = __drm_printfn_coredump,
+ .arg = iter,
+ };
+ return p;
+}
+
/**
* drm_seq_file_printer - construct a &drm_printer that outputs to &seq_file
* @f: the &struct seq_file to output to
--
2.16.1
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
