From: Jens Axboe <axboe@suse.de>
Date: Tue, 8 Nov 2005 08:20:58 +0000 (+0100)
Subject: [PATCH] fio: add size detection for block devices
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=c94deb1c1dfd93220efa54e03a73116669a6b96a;p=disktools.git

[PATCH] fio: add size detection for block devices
---

diff --git a/fio.c b/fio.c
index f546151..6366f22 100644
--- a/fio.c
+++ b/fio.c
@@ -39,6 +39,7 @@
 #include <semaphore.h>
 #include <sys/ipc.h>
 #include <sys/shm.h>
+#include <sys/ioctl.h>
 #include <asm/unistd.h>
 #include <asm/types.h>
 #include <asm/bitops.h>
@@ -46,6 +47,10 @@
 #include "list.h"
 #include "md5.h"
 
+#ifndef BLKGETSIZE64
+#define BLKGETSIZE64	_IOR(0x12,114,size_t)
+#endif
+
 #define MAX_JOBS	(1024)
 
 /*
@@ -1417,6 +1422,11 @@ static int create_file(struct thread_data *td)
 		return 1;
 	}
 
+	if (ftruncate(td->fd, td->file_size) == -1) {
+		td->error = errno;
+		return 1;
+	}
+
 	td->io_size = td->file_size;
 	b = malloc(td->max_bs);
 	memset(b, 0, td->max_bs);
@@ -1461,9 +1471,58 @@ static int file_exists(struct thread_data *td)
 	return errno != ENOENT;
 }
 
-static int setup_file(struct thread_data *td)
+static int get_file_size(struct thread_data *td)
 {
+	size_t bytes = 0;
 	struct stat st;
+
+	if (fstat(td->fd, &st) == -1) {
+		td->error = errno;
+		return 1;
+	}
+
+	/*
+	 * if block device, get size via BLKGETSIZE64 ioctl. try that as well
+	 * if this is a link, fall back to st.st_size if it fails
+	 */
+	if (S_ISBLK(st.st_mode) || S_ISLNK(st.st_mode)) {
+		if (ioctl(td->fd, BLKGETSIZE64, &bytes)) {
+			if (S_ISBLK(st.st_mode)) {
+				td->error = errno;
+				return 1;
+			} else
+				bytes = st.st_size;
+		}
+	} else
+		bytes = st.st_size;
+
+	if (td_read(td)) {
+		if (td->file_size > bytes)
+			bytes = td->file_size;
+	} else {
+		if (!td->file_size)
+			td->file_size = 1024 * 1024 * 1024;
+
+		bytes = td->file_size;
+	}
+
+	if (td->file_offset > bytes) {
+		fprintf(stderr, "Client%d: offset larger than length\n", td->thread_number);
+		return 1;
+	}
+
+	td->io_size = bytes - td->file_offset;
+	if (td->io_size == 0) {
+		fprintf(stderr, "Client%d: no io blocks\n", td->thread_number);
+		td->error = EINVAL;
+		return 1;
+	}
+
+	return 0;
+}
+
+static int setup_file(struct thread_data *td)
+{
 	int flags = 0;
 
 	if (!file_exists(td)) {
@@ -1498,35 +1557,16 @@ static int setup_file(struct thread_data *td)
 		return 1;
 	}
 
-	if (td_read(td)) {
-		if (fstat(td->fd, &st) == -1) {
-			td->error = errno;
-			return 1;
-		}
-
-		if (td->file_size > st.st_size)
-			st.st_size = td->file_size;
-	} else {
-		if (!td->file_size)
-			td->file_size = 1024 * 1024 * 1024;
-
-		st.st_size = td->file_size;
-	}
-
-	if (td->file_offset > st.st_size) {
-		fprintf(stderr, "Client%d: offset larger than length\n", td->thread_number);
+	if (get_file_size(td))
 		return 1;
-	}
 
-	td->io_size = st.st_size - td->file_offset;
-	if (td->io_size == 0) {
-		fprintf(stderr, "Client%d: no io blocks\n", td->thread_number);
-		td->error = EINVAL;
+	if (!td_read(td) && ftruncate(td->fd, td->file_size) == -1) {
+		td->error = errno;
 		return 1;
 	}
 
 	if (td->invalidate_cache) {
-		if (fadvise(td->fd, 0, st.st_size, POSIX_FADV_DONTNEED) < 0) {
+		if (fadvise(td->fd, td->file_offset, td->file_size, POSIX_FADV_DONTNEED) < 0) {
 			td->error = errno;
 			return 1;
 		}