1 files changed, 20 insertions, 36 deletions

diff --git a/lib/buildid.c b/lib/buildid.c
index c4b0f376fb34..aaf61dfc0919 100644
--- a/lib/buildid.c
+++ b/lib/buildid.c
@@ -11,27 +11,8 @@
 
 #define MAX_PHDR_CNT 256
 
-struct freader {
-	void *buf;
-	u32 buf_sz;
-	int err;
-	union {
-		struct {
-			struct file *file;
-			struct folio *folio;
-			void *addr;
-			loff_t folio_off;
-			bool may_fault;
-		};
-		struct {
-			const char *data;
-			u64 data_sz;
-		};
-	};
-};
-
-static void freader_init_from_file(struct freader *r, void *buf, u32 buf_sz,
-				   struct file *file, bool may_fault)
+void freader_init_from_file(struct freader *r, void *buf, u32 buf_sz,
+			    struct file *file, bool may_fault)
 {
 	memset(r, 0, sizeof(*r));
 	r->buf = buf;
@@ -40,7 +21,7 @@ static void freader_init_from_file(struct freader *r, void *buf, u32 buf_sz,
 	r->may_fault = may_fault;
 }
 
-static void freader_init_from_mem(struct freader *r, const char *data, u64 data_sz)
+void freader_init_from_mem(struct freader *r, const char *data, u64 data_sz)
 {
 	memset(r, 0, sizeof(*r));
 	r->data = data;
@@ -92,7 +73,7 @@ static int freader_get_folio(struct freader *r, loff_t file_off)
 	return 0;
 }
 
-static const void *freader_fetch(struct freader *r, loff_t file_off, size_t sz)
+const void *freader_fetch(struct freader *r, loff_t file_off, size_t sz)
 {
 	size_t folio_sz;
 
@@ -127,18 +108,21 @@ static const void *freader_fetch(struct freader *r, loff_t file_off, size_t sz)
 	 */
 	folio_sz = folio_size(r->folio);
 	if (file_off + sz > r->folio_off + folio_sz) {
-		int part_sz = r->folio_off + folio_sz - file_off;
-
-		/* copy the part that resides in the current folio */
-		memcpy(r->buf, r->addr + (file_off - r->folio_off), part_sz);
-
-		/* fetch next folio */
-		r->err = freader_get_folio(r, r->folio_off + folio_sz);
-		if (r->err)
-			return NULL;
-
-		/* copy the rest of requested data */
-		memcpy(r->buf + part_sz, r->addr, sz - part_sz);
+		u64 part_sz = r->folio_off + folio_sz - file_off, off;
+
+		memcpy(r->buf, r->addr + file_off - r->folio_off, part_sz);
+		off = part_sz;
+
+		while (off < sz) {
+			/* fetch next folio */
+			r->err = freader_get_folio(r, r->folio_off + folio_sz);
+			if (r->err)
+				return NULL;
+			folio_sz = folio_size(r->folio);
+			part_sz = min_t(u64, sz - off, folio_sz);
+			memcpy(r->buf + off, r->addr, part_sz);
+			off += part_sz;
+		}
 
 		return r->buf;
 	}
@@ -147,7 +131,7 @@ static const void *freader_fetch(struct freader *r, loff_t file_off, size_t sz)
 	return r->addr + (file_off - r->folio_off);
 }
 
-static void freader_cleanup(struct freader *r)
+void freader_cleanup(struct freader *r)
 {
 	if (!r->buf)
 		return; /* non-file-backed mode */