MFC 272384:

Improve performance of mking(1).

Requested by: gjb

2 files changed, 586 insertions, 94 deletions

diff --git a/usr.bin/mkimg/Makefile b/usr.bin/mkimg/Makefile
index bc7baed..569f465 100644
--- a/usr.bin/mkimg/Makefile
+++ b/usr.bin/mkimg/Makefile
@@ -4,7 +4,7 @@ PROG=	mkimg
 SRCS=	format.c image.c mkimg.c scheme.c
 MAN=	mkimg.1
 
-MKIMG_VERSION=20140927
+MKIMG_VERSION=20141001
 CFLAGS+=-DMKIMG_VERSION=${MKIMG_VERSION}
 CFLAGS+=-DSPARSE_WRITE
 
diff --git a/usr.bin/mkimg/image.c b/usr.bin/mkimg/image.c
index f448d98..3e7c7d2 100644
--- a/usr.bin/mkimg/image.c
+++ b/usr.bin/mkimg/image.c
@@ -27,71 +27,462 @@
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
+#include <sys/mman.h>
+#include <sys/queue.h>
+#include <sys/stat.h>
 #include <sys/types.h>
 #include <assert.h>
 #include <errno.h>
 #include <limits.h>
 #include <paths.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 
 #include "image.h"
 #include "mkimg.h"
 
-#define	BUFFER_SIZE	(1024*1024)
+struct chunk {
+	STAILQ_ENTRY(chunk) ch_list;
+	size_t	ch_size;		/* Size of chunk in bytes. */
+	lba_t	ch_block;		/* Block address in image. */
+	union {
+		struct {
+			off_t	ofs;	/* Offset in backing file. */
+			int	fd;	/* FD of backing file. */
+		} file;
+		struct {
+			void	*ptr;	/* Pointer to data in memory */
+		} mem;
+	} ch_u;
+	u_int	ch_type;
+#define	CH_TYPE_ZEROES		0	/* Chunk is a gap (no data). */
+#define	CH_TYPE_FILE		1	/* File-backed chunk. */
+#define	CH_TYPE_MEMORY		2	/* Memory-backed chunk */
+};
+
+static STAILQ_HEAD(chunk_head, chunk) image_chunks;
+static u_int image_nchunks;
+
+static char image_swap_file[PATH_MAX];
+static int image_swap_fd = -1;
+static u_int image_swap_pgsz;
+static off_t image_swap_size;
 
-static char image_tmpfile[PATH_MAX];
-static int image_fd = -1;
 static lba_t image_size;
 
-static void
-cleanup(void)
+static int
+is_empty_sector(void *buf)
 {
+	uint64_t *p = buf;
+	size_t n, max;
+
+	assert(((uintptr_t)p & 3) == 0);
 
-	if (image_fd != -1)
-		close(image_fd);
-	unlink(image_tmpfile);
+	max = secsz / sizeof(uint64_t);
+	for (n = 0; n < max; n++) {
+		if (p[n] != 0UL)
+			return (0);
+	}
+	return (1);
 }
 
-int
-image_copyin(lba_t blk, int fd, uint64_t *sizep)
+/*
+ * Swap file handlng.
+ */
+
+static off_t
+image_swap_alloc(size_t size)
+{
+	off_t ofs;
+	size_t unit;
+
+	unit = (secsz > image_swap_pgsz) ? secsz : image_swap_pgsz;
+	assert((unit & (unit - 1)) == 0);
+
+	size = (size + unit - 1) & ~(unit - 1);
+
+	ofs = image_swap_size;
+	image_swap_size += size;
+	if (ftruncate(image_swap_fd, image_swap_size) == -1) {
+		image_swap_size = ofs;
+		ofs = -1LL;
+	}
+	return (ofs);
+}
+
+/*
+ * Image chunk handling.
+ */
+
+static struct chunk *
+image_chunk_find(lba_t blk)
+{
+	static struct chunk *last = NULL;
+	struct chunk *ch;
+
+	ch = (last != NULL && last->ch_block <= blk)
+	    ? last : STAILQ_FIRST(&image_chunks);
+	while (ch != NULL) {
+		if (ch->ch_block <= blk &&
+		    (lba_t)(ch->ch_block + (ch->ch_size / secsz)) > blk) {
+			last = ch;
+			break;
+		}
+		ch = STAILQ_NEXT(ch, ch_list);
+	}
+	return (ch);
+}
+
+static size_t
+image_chunk_grow(struct chunk *ch, size_t sz)
+{
+	size_t dsz, newsz;
+
+	newsz = ch->ch_size + sz;
+	if (newsz > ch->ch_size) {
+		ch->ch_size = newsz;
+		return (0);
+	}
+	/* We would overflow -- create new chunk for remainder. */
+	dsz = SIZE_MAX - ch->ch_size;
+	assert(dsz < sz);
+	ch->ch_size = SIZE_MAX;
+	return (sz - dsz);
+}
+
+static struct chunk *
+image_chunk_memory(struct chunk *ch, lba_t blk)
+{
+	struct chunk *new;
+	void *ptr;
+
+	ptr = calloc(1, secsz);
+	if (ptr == NULL)
+		return (NULL);
+
+	if (ch->ch_block < blk) {
+		new = malloc(sizeof(*new));
+		if (new == NULL) {
+			free(ptr);
+			return (NULL);
+		}
+		memcpy(new, ch, sizeof(*new));
+		ch->ch_size = (blk - ch->ch_block) * secsz;
+		new->ch_block = blk;
+		new->ch_size -= ch->ch_size;
+		STAILQ_INSERT_AFTER(&image_chunks, ch, new, ch_list);
+		image_nchunks++;
+		ch = new;
+	}
+
+	if (ch->ch_size > secsz) {
+		new = malloc(sizeof(*new));
+		if (new == NULL) {
+			free(ptr);
+			return (NULL);
+		}
+		memcpy(new, ch, sizeof(*new));
+		ch->ch_size = secsz;
+		new->ch_block++;
+		new->ch_size -= secsz;
+		STAILQ_INSERT_AFTER(&image_chunks, ch, new, ch_list);
+		image_nchunks++;
+	}
+
+	ch->ch_type = CH_TYPE_MEMORY;
+	ch->ch_u.mem.ptr = ptr;
+	return (ch);
+}
+
+static int
+image_chunk_skipto(lba_t to)
+{
+	struct chunk *ch;
+	lba_t from;
+	size_t sz;
+
+	ch = STAILQ_LAST(&image_chunks, chunk, ch_list);
+	from = (ch != NULL) ? ch->ch_block + (ch->ch_size / secsz) : 0LL;
+
+	assert(from <= to);
+
+	/* Nothing to do? */
+	if (from == to)
+		return (0);
+	/* Avoid bugs due to overflows. */
+	if ((uintmax_t)(to - from) > (uintmax_t)(SIZE_MAX / secsz))
+		return (EFBIG);
+	sz = (to - from) * secsz;
+	if (ch != NULL && ch->ch_type == CH_TYPE_ZEROES) {
+		sz = image_chunk_grow(ch, sz);
+		if (sz == 0)
+			return (0);
+		from = ch->ch_block + (ch->ch_size / secsz);
+	}
+	ch = malloc(sizeof(*ch));
+	if (ch == NULL)
+		return (ENOMEM);
+	memset(ch, 0, sizeof(*ch));
+	ch->ch_block = from;
+	ch->ch_size = sz;
+	ch->ch_type = CH_TYPE_ZEROES;
+	STAILQ_INSERT_TAIL(&image_chunks, ch, ch_list);
+	image_nchunks++;
+	return (0);
+}
+
+static int
+image_chunk_append(lba_t blk, size_t sz, off_t ofs, int fd)
+{
+	struct chunk *ch;
+
+	ch = STAILQ_LAST(&image_chunks, chunk, ch_list);
+	if (ch != NULL && ch->ch_type == CH_TYPE_FILE) {
+		if (fd == ch->ch_u.file.fd &&
+		    blk == (lba_t)(ch->ch_block + (ch->ch_size / secsz)) &&
+		    ofs == (off_t)(ch->ch_u.file.ofs + ch->ch_size)) {
+			sz = image_chunk_grow(ch, sz);
+			if (sz == 0)
+				return (0);
+			blk = ch->ch_block + (ch->ch_size / secsz);
+			ofs = ch->ch_u.file.ofs + ch->ch_size;
+		}
+	}
+	ch = malloc(sizeof(*ch));
+	if (ch == NULL)
+		return (ENOMEM);
+	memset(ch, 0, sizeof(*ch));
+	ch->ch_block = blk;
+	ch->ch_size = sz;
+	ch->ch_type = CH_TYPE_FILE;
+	ch->ch_u.file.ofs = ofs;
+	ch->ch_u.file.fd = fd;
+	STAILQ_INSERT_TAIL(&image_chunks, ch, ch_list);
+	image_nchunks++;
+	return (0);
+}
+
+static int
+image_chunk_copyin(lba_t blk, void *buf, size_t sz, off_t ofs, int fd)
+{
+	uint8_t *p = buf;
+	int error;
+
+	error = 0;
+	sz = (sz + secsz - 1) & ~(secsz - 1);
+	while (!error && sz > 0) {
+		if (is_empty_sector(p))
+			error = image_chunk_skipto(blk + 1);
+		else
+			error = image_chunk_append(blk, secsz, ofs, fd);
+		blk++;
+		p += secsz;
+		sz -= secsz;
+		ofs += secsz;
+	}
+	return (error);
+}
+
+/*
+ * File mapping support.
+ */
+
+static void *
+image_file_map(int fd, off_t ofs, size_t sz)
+{
+	void *ptr;
+	size_t unit;
+	int flags, prot;
+
+	unit = (secsz > image_swap_pgsz) ? secsz : image_swap_pgsz;
+	assert((unit & (unit - 1)) == 0);
+
+	flags = MAP_NOCORE | MAP_NOSYNC | MAP_SHARED;
+	/* Allow writing to our swap file only. */
+	prot = PROT_READ | ((fd == image_swap_fd) ? PROT_WRITE : 0);
+	sz = (sz + unit - 1) & ~(unit - 1);
+	ptr = mmap(NULL, sz, prot, flags, fd, ofs);
+	return ((ptr == MAP_FAILED) ? NULL : ptr);
+}
+
+static int
+image_file_unmap(void *buffer, size_t sz)
+{
+	size_t unit;
+
+	unit = (secsz > image_swap_pgsz) ? secsz : image_swap_pgsz;
+	sz = (sz + unit - 1) & ~(unit - 1);
+	munmap(buffer, sz);
+	return (0);
+}
+
+/*
+ * Input/source file handling.
+ */
+
+static int
+image_copyin_stream(lba_t blk, int fd, uint64_t *sizep)
 {
 	char *buffer;
 	uint64_t bytesize;
-	ssize_t bcnt, rdsz;
-	int error, partial;
+	off_t swofs;
+	size_t iosz;
+	ssize_t rdsz;
+	int error;
 
-	assert(BUFFER_SIZE % secsz == 0);
+	/*
+	 * This makes sure we're doing I/O in multiples of the page
+	 * size as well as of the sector size. 2MB is the minimum
+	 * by virtue of secsz at least 512 bytes and the page size
+	 * at least 4K bytes.
+	 */
+	iosz = secsz * image_swap_pgsz;
 
-	buffer = malloc(BUFFER_SIZE);
-	if (buffer == NULL)
-		return (ENOMEM);
 	bytesize = 0;
-	partial = 0;
-	while (1) {
-		rdsz = read(fd, buffer, BUFFER_SIZE);
-		if (rdsz <= 0) {
-			error = (rdsz < 0) ? errno : 0;
-			break;
-		}
-		if (partial)
-			abort();
-		bytesize += rdsz;
-		bcnt = (rdsz + secsz - 1) / secsz;
-		error = image_write(blk, buffer, bcnt);
+	do {
+		swofs = image_swap_alloc(iosz);
+		if (swofs == -1LL)
+			return (errno);
+		buffer = image_file_map(image_swap_fd, swofs, iosz);
+		if (buffer == NULL)
+			return (errno);
+		rdsz = read(fd, buffer, iosz);
+		if (rdsz > 0)
+			error = image_chunk_copyin(blk, buffer, rdsz, swofs,
+			    image_swap_fd);
+		else if (rdsz < 0)
+			error = errno;
+		else
+			error = 0;
+		image_file_unmap(buffer, iosz);
+		/* XXX should we relinguish unused swap space? */
 		if (error)
+			return (error);
+
+		bytesize += rdsz;
+		blk += (rdsz + secsz - 1) / secsz;
+	} while (rdsz > 0);
+
+	if (sizep != NULL)
+		*sizep = bytesize;
+	return (0);
+}
+
+static int
+image_copyin_mapped(lba_t blk, int fd, uint64_t *sizep)
+{
+	off_t cur, data, end, hole, pos;
+	void *buf;
+	uint64_t bytesize;
+	size_t iosz, sz;
+	int error;
+
+	/*
+	 * We'd like to know the size of the file and we must
+	 * be able to seek in order to mmap(2). If this isn't
+	 * possible, then treat the file as a stream/pipe.
+	 */
+	end = lseek(fd, 0L, SEEK_END);
+	if (end == -1L)
+		return (image_copyin_stream(blk, fd, sizep));
+
+	/*
+	 * We need the file opened for the duration and our
+	 * caller is going to close the file. Make a dup(2)
+	 * so that control the faith of the descriptor.
+	 */
+	fd = dup(fd);
+	if (fd == -1)
+		return (errno);
+
+	iosz = secsz * image_swap_pgsz;
+
+	bytesize = 0;
+	cur = pos = 0;
+	error = 0;
+	while (!error && cur < end) {
+		hole = lseek(fd, cur, SEEK_HOLE);
+		data = lseek(fd, cur, SEEK_DATA);
+
+		/*
+		 * Treat the entire file as data if sparse files
+		 * are not supported by the underlying file system.
+		 */
+		if (hole == -1 && data == -1) {
+			data = cur;
+			hole = end;
+		}
+
+		if (cur == hole && data > hole) {
+			hole = pos;
+			pos = data & ~((uint64_t)secsz - 1);
+
+			blk += (pos - hole) / secsz;
+			error = image_chunk_skipto(blk);
+
+			bytesize += pos - hole;
+			cur = data;
+		} else if (cur == data && hole > data) {
+			data = pos;
+			pos = (hole + secsz - 1) & ~((uint64_t)secsz - 1);
+
+			while (data < pos) {
+				sz = (pos - data > (off_t)iosz)
+				    ? iosz : (size_t)(pos - data);
+
+				buf = image_file_map(fd, data, sz);
+				if (buf != NULL) {
+					error = image_chunk_copyin(blk, buf,
+					    sz, data, fd);
+					image_file_unmap(buf, sz);
+				} else
+					error = errno;
+
+				blk += sz / secsz;
+				bytesize += sz;
+				data += sz;
+			}
+			cur = hole;
+		} else {
+			/*
+			 * I don't know what this means or whether it
+			 * can happen at all...
+			 */
+			error = EDOOFUS;
 			break;
-		blk += bcnt;
-		partial = ((ssize_t)(bcnt * secsz) != rdsz) ? 1 : 0;
+		}
 	}
-	free(buffer);
-	if (sizep != NULL)
+	if (error)
+		close(fd);
+	if (!error && sizep != NULL)
 		*sizep = bytesize;
 	return (error);
 }
 
 int
+image_copyin(lba_t blk, int fd, uint64_t *sizep)
+{
+	struct stat sb;
+	int error;
+
+	error = image_chunk_skipto(blk);
+	if (!error) {
+		if (fstat(fd, &sb) == -1 || !S_ISREG(sb.st_mode))
+			error = image_copyin_stream(blk, fd, sizep);
+		else
+			error = image_copyin_mapped(blk, fd, sizep);
+	}
+	return (error);
+}
+
+/*
+ * Output/sink file handling.
+ */
+
+int
 image_copyout(int fd)
 {
 	int error;
@@ -115,71 +506,124 @@ image_copyout_done(int fd)
 	return (error);
 }
 
-int
-image_copyout_region(int fd, lba_t blk, lba_t size)
+static int
+image_copyout_memory(int fd, size_t size, void *ptr)
 {
-	char *buffer;
-	off_t ofs;
+
+	if (write(fd, ptr, size) == -1)
+		return (errno);
+	return (0);
+}
+
+static int
+image_copyout_zeroes(int fd, size_t size)
+{
+	static uint8_t *zeroes = NULL;
 	size_t sz;
-	ssize_t rdsz, wrsz;
 	int error;
 
-	ofs = lseek(fd, 0L, SEEK_CUR);
+	if (lseek(fd, (off_t)size, SEEK_CUR) != -1)
+		return (0);
+
+	/*
+	 * If we can't seek, we must write.
+	 */
+
+	if (zeroes == NULL) {
+		zeroes = calloc(1, secsz);
+		if (zeroes == NULL)
+			return (ENOMEM);
+	}
+
+	while (size > 0) {
+		sz = (size > secsz) ? secsz : size;
+		error = image_copyout_memory(fd, sz, zeroes);
+		if (error)
+			return (error);
+		size -= sz;
+	}
+	return (0);
+}
+
+static int
+image_copyout_file(int fd, size_t size, int ifd, off_t iofs)
+{
+	void *buf;
+	size_t iosz, sz;
+	int error;
+
+	iosz = secsz * image_swap_pgsz;
+
+	while (size > 0) {
+		sz = (size > iosz) ? iosz : size;
+		buf = image_file_map(ifd, iofs, sz);
+		if (buf == NULL)
+			return (errno);
+		error = image_copyout_memory(fd, sz, buf);
+		image_file_unmap(buf, sz);
+		if (error)
+			return (error);
+		size -= sz;
+		iofs += sz;
+	}
+	return (0);
+}
+
+int
+image_copyout_region(int fd, lba_t blk, lba_t size)
+{
+	struct chunk *ch;
+	size_t ofs, sz;
+	int error;
 
-	blk *= secsz;
-	if (lseek(image_fd, blk, SEEK_SET) != blk)
-		return (errno);
-	buffer = malloc(BUFFER_SIZE);
-	if (buffer == NULL)
-		return (errno);
-	error = 0;
 	size *= secsz;
+
 	while (size > 0) {
-		sz = (BUFFER_SIZE < size) ? BUFFER_SIZE : size;
-		rdsz = read(image_fd, buffer, sz);
-		if (rdsz <= 0) {
-			error = (rdsz < 0) ? errno : 0;
+		ch = image_chunk_find(blk);
+		if (ch == NULL)
+			return (EINVAL);
+		ofs = (blk - ch->ch_block) * secsz;
+		sz = ch->ch_size - ofs;
+		sz = ((lba_t)sz < size) ? sz : (size_t)size;
+		switch (ch->ch_type) {
+		case CH_TYPE_ZEROES:
+			error = image_copyout_zeroes(fd, sz);
 			break;
-		}
-		wrsz = (ofs == -1) ?
-		    write(fd, buffer, rdsz) :
-		    sparse_write(fd, buffer, rdsz);
-		if (wrsz < 0) {
-			error = errno;
+		case CH_TYPE_FILE:
+			error = image_copyout_file(fd, sz, ch->ch_u.file.fd,
+			    ch->ch_u.file.ofs + ofs);
+			break;
+		case CH_TYPE_MEMORY:
+			error = image_copyout_memory(fd, sz, ch->ch_u.mem.ptr);
 			break;
+		default:
+			return (EDOOFUS);
 		}
-		assert(wrsz == rdsz);
-		size -= rdsz;
+		size -= sz;
+		blk += sz / secsz;
 	}
-	free(buffer);
-	return (error);
+	return (0);
 }
 
 int
 image_data(lba_t blk, lba_t size)
 {
-	char *buffer, *p;
-
-	blk *= secsz;
-	if (lseek(image_fd, blk, SEEK_SET) != blk)
-		return (1);
-
-	size *= secsz;
-	buffer = malloc(size);
-	if (buffer == NULL)
-		return (1);
+	struct chunk *ch;
+	lba_t lim;
 
-	if (read(image_fd, buffer, size) != (ssize_t)size) {
-		free(buffer);
-		return (1);
+	while (1) {
+		ch = image_chunk_find(blk);
+		if (ch == NULL)
+			return (0);
+		if (ch->ch_type != CH_TYPE_ZEROES)
+			return (1);
+		lim = ch->ch_block + (ch->ch_size / secsz);
+		if (lim >= blk + size)
+			return (0);
+		size -= lim - blk;
+		blk = lim;
 	}
-
-	p = buffer;
-	while (size > 0 && *p == '\0')
-		size--, p++;
-
-	free(buffer);
-	return ((size == 0) ? 0 : 1);
+	/*NOTREACHED*/
 }
 
 lba_t
@@ -192,39 +636,87 @@ image_get_size(void)
 int
 image_set_size(lba_t blk)
 {
+	int error;
 
-	image_size = blk;
-	if (ftruncate(image_fd, blk * secsz) == -1)
-		return (errno);
-	return (0);
+	error = image_chunk_skipto(blk);
+	if (!error)
+		image_size = blk;
+	return (error);
 }
 
 int
 image_write(lba_t blk, void *buf, ssize_t len)
 {
+	struct chunk *ch;
 
-	blk *= secsz;
-	if (lseek(image_fd, blk, SEEK_SET) != blk)
-		return (errno);
-	len *= secsz;
-	if (sparse_write(image_fd, buf, len) != len)
-		return (errno);
+	while (len > 0) {
+		if (!is_empty_sector(buf)) {
+			ch = image_chunk_find(blk);
+			if (ch == NULL)
+				return (ENXIO);
+			/* We may not be able to write to files. */
+			if (ch->ch_type == CH_TYPE_FILE)
+				return (EINVAL);
+			if (ch->ch_type == CH_TYPE_ZEROES) {
+				ch = image_chunk_memory(ch, blk);
+				if (ch == NULL)
+					return (ENOMEM);
+			}
+			assert(ch->ch_type == CH_TYPE_MEMORY);
+			memcpy(ch->ch_u.mem.ptr, buf, secsz);
+		}
+		blk++;
+		buf = (char *)buf + secsz;
+		len--;
+	}
 	return (0);
 }
 
+static void
+image_cleanup(void)
+{
+	struct chunk *ch;
+
+	while ((ch = STAILQ_FIRST(&image_chunks)) != NULL) {
+		switch (ch->ch_type) {
+		case CH_TYPE_FILE:
+			/* We may be closing the same file multiple times. */
+			if (ch->ch_u.file.fd != -1)
+				close(ch->ch_u.file.fd);
+			break;
+		case CH_TYPE_MEMORY:
+			free(ch->ch_u.mem.ptr);
+			break;
+		default:
+			break;
+		}
+		STAILQ_REMOVE_HEAD(&image_chunks, ch_list);
+		free(ch);
+	}
+	if (image_swap_fd != -1)
+		close(image_swap_fd);
+	unlink(image_swap_file);
+}
+
 int
 image_init(void)
 {
 	const char *tmpdir;
 
-	if (atexit(cleanup) == -1)
+	STAILQ_INIT(&image_chunks);
+	image_nchunks = 0;
+
+	image_swap_size = 0;
+	image_swap_pgsz = getpagesize();
+
+	if (atexit(image_cleanup) == -1)
 		return (errno);
 	if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
 		tmpdir = _PATH_TMP;
-	snprintf(image_tmpfile, sizeof(image_tmpfile), "%s/mkimg-XXXXXX",
+	snprintf(image_swap_file, sizeof(image_swap_file), "%s/mkimg-XXXXXX",
 	    tmpdir);
-	image_fd = mkstemp(image_tmpfile);
-	if (image_fd == -1)
+	image_swap_fd = mkstemp(image_swap_file);
+	if (image_swap_fd == -1)
 		return (errno);
 	return (0);
 }