Date: Wed, 1 Oct 2014 21:03:17 +0000 (UTC) From: Marcel Moolenaar <marcel@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r272384 - head/usr.bin/mkimg Message-ID: <201410012103.s91L3HR0010906@svn.freebsd.org>
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Author: marcel Date: Wed Oct 1 21:03:17 2014 New Revision: 272384 URL: https://svnweb.freebsd.org/changeset/base/272384 Log: Improve performance of mking(1) by keeping a list of "chunks" in memory, that keeps track of a particular region of the image. In particular the image_data() function needs to return to the caller whether a region contains data or is all zeroes. This required reading the region from the temporary file and comparing the bytes. When image_data() is used multiple times for the same region, this will get painful fast. With a chunk describing a region of the image, we now also have a way to refer to the image provided on the command line. This means we don't need to copy the image into a temporary file. We just keep track of the file descriptor and offset within the source file on a per-chunk basis. For streams (pipes, sockets, fifos, etc) we now use the temporary file as a swap file. We read from the input file and create a chunk of type "zeroes" for each sequence of zeroes that's a multiple of the sector size. Otherwise, we allocte from the swap file, mmap(2) it, read into the mmap(2)'d memory and create a chunk representing data. For regular files, we use SEEK_HOLE and SEEK_DATA to handle sparse files eficiently and create a chunk of type zeroes for holes and a chunk of type data for data regions. For data regions, we still compare the bytes we read to handle differences between a file system's block size and our sector size. After reading all files, image_write() is used by schemes to scribble in the reserved sectors. Since this never amounts to much, keep this data in memory in chunks of exactly 1 sector. The output image is created by looking using the chunk list to find the data and write it out to the output file. For chunks of type "zeroes" we prefer to seek, but fall back to writing zeroes to handle pipes. For chunks of type "file" and "memoty" we simply write. The net effect of this is that for reasonably large images the execution time drops from 1-2 minutes to 10-20 seconds. A typical speedup is about 5 to 8 times, depending on partition sizes, output format whether in input files are sparse or not. Bump version to 20141001. Modified: head/usr.bin/mkimg/Makefile head/usr.bin/mkimg/image.c Directory Properties: head/usr.bin/mkimg/ (props changed) Modified: head/usr.bin/mkimg/Makefile ============================================================================== --- head/usr.bin/mkimg/Makefile Wed Oct 1 20:52:08 2014 (r272383) +++ head/usr.bin/mkimg/Makefile Wed Oct 1 21:03:17 2014 (r272384) @@ -6,7 +6,7 @@ PROG= mkimg SRCS= format.c image.c mkimg.c scheme.c MAN= mkimg.1 -MKIMG_VERSION=20140927 +MKIMG_VERSION=20141001 CFLAGS+=-DMKIMG_VERSION=${MKIMG_VERSION} CFLAGS+=-DSPARSE_WRITE Modified: head/usr.bin/mkimg/image.c ============================================================================== --- head/usr.bin/mkimg/image.c Wed Oct 1 20:52:08 2014 (r272383) +++ head/usr.bin/mkimg/image.c Wed Oct 1 21:03:17 2014 (r272384) @@ -27,71 +27,462 @@ #include <sys/cdefs.h> __FBSDID("$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); + struct chunk *ch; + lba_t lim; - size *= secsz; - buffer = malloc(size); - if (buffer == NULL) - return (1); - - 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); }
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