/*
* unix_io.c --- This is the Unix (well, really POSIX) implementation
- * of the I/O manager.
+ * of the I/O manager.
*
* Implements a one-block write-through cache.
*
* Includes support for Windows NT support under Cygwin.
*
* Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
- * 2002 by Theodore Ts'o.
+ * 2002 by Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Library
* %End-Header%
*/
+#define _XOPEN_SOURCE 600
+#define _DARWIN_C_SOURCE
+#define _FILE_OFFSET_BITS 64
#define _LARGEFILE_SOURCE
#define _LARGEFILE64_SOURCE
+#ifndef _GNU_SOURCE
#define _GNU_SOURCE
+#endif
+#include "config.h"
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#ifdef __linux__
#include <sys/utsname.h>
#endif
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#if HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
-#if HAVE_SYS_TYPES_H
-#include <sys/types.h>
-#endif
#if HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
+#if HAVE_LINUX_FALLOC_H
+#include <linux/falloc.h>
+#endif
#if defined(__linux__) && defined(_IO) && !defined(BLKROGET)
#define BLKROGET _IO(0x12, 94) /* Get read-only status (0 = read_write). */
#endif
-#if defined(__linux__) && defined(_IO) && !defined(BLKSSZGET)
-#define BLKSSZGET _IO(0x12,104)/* get block device sector size */
-#endif
-
#undef ALIGN_DEBUG
#include "ext2_fs.h"
if ((struct)->magic != (code)) return (code)
struct unix_cache {
- char *buf;
- unsigned long block;
- int access_time;
- unsigned dirty:1;
- unsigned in_use:1;
+ char *buf;
+ unsigned long long block;
+ int access_time;
+ unsigned dirty:1;
+ unsigned in_use:1;
};
#define CACHE_SIZE 8
#define IS_ALIGNED(n, align) ((((unsigned long) n) & \
((unsigned long) ((align)-1))) == 0)
-static errcode_t unix_open(const char *name, int flags, io_channel *channel);
-static errcode_t unix_close(io_channel channel);
-static errcode_t unix_set_blksize(io_channel channel, int blksize);
-static errcode_t unix_read_blk(io_channel channel, unsigned long block,
- int count, void *data);
-static errcode_t unix_write_blk(io_channel channel, unsigned long block,
- int count, const void *data);
-static errcode_t unix_flush(io_channel channel);
-static errcode_t unix_write_byte(io_channel channel, unsigned long offset,
- int size, const void *data);
-static errcode_t unix_set_option(io_channel channel, const char *option,
- const char *arg);
-static errcode_t unix_get_stats(io_channel channel, io_stats *stats)
-;
-static void reuse_cache(io_channel channel, struct unix_private_data *data,
- struct unix_cache *cache, unsigned long long block);
-static errcode_t unix_read_blk64(io_channel channel, unsigned long long block,
- int count, void *data);
-static errcode_t unix_write_blk64(io_channel channel, unsigned long long block,
- int count, const void *data);
-
-static struct struct_io_manager struct_unix_manager = {
- EXT2_ET_MAGIC_IO_MANAGER,
- "Unix I/O Manager",
- unix_open,
- unix_close,
- unix_set_blksize,
- unix_read_blk,
- unix_write_blk,
- unix_flush,
- unix_write_byte,
- unix_set_option,
- unix_get_stats,
- unix_read_blk64,
- unix_write_blk64,
-};
-
-io_manager unix_io_manager = &struct_unix_manager;
-
static errcode_t unix_get_stats(io_channel channel, io_stats *stats)
{
- errcode_t retval = 0;
+ errcode_t retval = 0;
struct unix_private_data *data;
static errcode_t raw_read_blk(io_channel channel,
struct unix_private_data *data,
unsigned long long block,
- int count, void *buf)
+ int count, void *bufv)
{
errcode_t retval;
ssize_t size;
ext2_loff_t location;
int actual = 0;
+ unsigned char *buf = bufv;
size = (count < 0) ? -count : count * channel->block_size;
data->io_stats.bytes_read += size;
location = ((ext2_loff_t) block * channel->block_size) + data->offset;
+
+#ifdef HAVE_PREAD64
+ /* Try an aligned pread */
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
+ actual = pread64(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ }
+#elif HAVE_PREAD
+ /* Try an aligned pread */
+ if ((sizeof(off_t) >= sizeof(ext2_loff_t)) &&
+ ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align)))) {
+ actual = pread(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ }
+#endif /* HAVE_PREAD */
+
if (ext2fs_llseek(data->dev, location, SEEK_SET) != location) {
retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
goto error_out;
}
- if ((data->align == 0) ||
- ((IS_ALIGNED(buf, data->align)) && IS_ALIGNED(size, data->align))) {
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
actual = read(data->dev, buf, size);
if (actual != size) {
short_read:
static errcode_t raw_write_blk(io_channel channel,
struct unix_private_data *data,
unsigned long long block,
- int count, const void *buf)
+ int count, const void *bufv)
{
ssize_t size;
ext2_loff_t location;
int actual = 0;
errcode_t retval;
+ const unsigned char *buf = bufv;
if (count == 1)
size = channel->block_size;
data->io_stats.bytes_written += size;
location = ((ext2_loff_t) block * channel->block_size) + data->offset;
+
+#ifdef HAVE_PWRITE64
+ /* Try an aligned pwrite */
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
+ actual = pwrite64(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ }
+#elif HAVE_PWRITE
+ /* Try an aligned pwrite */
+ if ((sizeof(off_t) >= sizeof(ext2_loff_t)) &&
+ ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align)))) {
+ actual = pwrite(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ }
+#endif /* HAVE_PWRITE */
+
if (ext2fs_llseek(data->dev, location, SEEK_SET) != location) {
retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
goto error_out;
}
- if ((data->align == 0) ||
- ((IS_ALIGNED(buf, data->align)) && IS_ALIGNED(size, data->align))) {
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
actual = write(data->dev, buf, size);
if (actual != size) {
short_write:
cache->in_use = 0;
if (cache->buf)
ext2fs_free_mem(&cache->buf);
- retval = ext2fs_get_memalign(channel->block_size,
- data->align, &cache->buf);
+ retval = io_channel_alloc_buf(channel, 0, &cache->buf);
if (retval)
return retval;
}
- if (data->align) {
+ if (channel->align) {
if (data->bounce)
ext2fs_free_mem(&data->bounce);
- retval = ext2fs_get_memalign(channel->block_size, data->align,
- &data->bounce);
+ retval = io_channel_alloc_buf(channel, 0, &data->bounce);
}
return retval;
}
}
#endif /* NO_IO_CACHE */
+#ifdef __linux__
+#ifndef BLKDISCARDZEROES
+#define BLKDISCARDZEROES _IO(0x12,124)
+#endif
+#endif
+
+int ext2fs_open_file(const char *pathname, int flags, mode_t mode)
+{
+ if (mode)
+#if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
+ return open64(pathname, flags, mode);
+ else
+ return open64(pathname, flags);
+#else
+ return open(pathname, flags, mode);
+ else
+ return open(pathname, flags);
+#endif
+}
+
+int ext2fs_stat(const char *path, ext2fs_struct_stat *buf)
+{
+#if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
+ return stat64(path, buf);
+#else
+ return stat(path, buf);
+#endif
+}
+
+int ext2fs_fstat(int fd, ext2fs_struct_stat *buf)
+{
+#if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
+ return fstat64(fd, buf);
+#else
+ return fstat(fd, buf);
+#endif
+}
+
static errcode_t unix_open(const char *name, int flags, io_channel *channel)
{
io_channel io = NULL;
struct unix_private_data *data = NULL;
errcode_t retval;
int open_flags;
- struct stat st;
+ int f_nocache = 0;
+ ext2fs_struct_stat st;
#ifdef __linux__
- struct utsname ut;
+ struct utsname ut;
#endif
if (name == 0)
return EXT2_ET_BAD_DEVICE_NAME;
retval = ext2fs_get_mem(sizeof(struct struct_io_channel), &io);
if (retval)
- return retval;
+ goto cleanup;
memset(io, 0, sizeof(struct struct_io_channel));
io->magic = EXT2_ET_MAGIC_IO_CHANNEL;
retval = ext2fs_get_mem(sizeof(struct unix_private_data), &data);
memset(data, 0, sizeof(struct unix_private_data));
data->magic = EXT2_ET_MAGIC_UNIX_IO_CHANNEL;
data->io_stats.num_fields = 2;
+ data->dev = -1;
open_flags = (flags & IO_FLAG_RW) ? O_RDWR : O_RDONLY;
if (flags & IO_FLAG_EXCLUSIVE)
open_flags |= O_EXCL;
- if (flags & IO_FLAG_DIRECT_IO)
+#if defined(O_DIRECT)
+ if (flags & IO_FLAG_DIRECT_IO) {
open_flags |= O_DIRECT;
+ io->align = ext2fs_get_dio_alignment(data->dev);
+ }
+#elif defined(F_NOCACHE)
+ if (flags & IO_FLAG_DIRECT_IO) {
+ f_nocache = F_NOCACHE;
+ io->align = 4096;
+ }
+#endif
data->flags = flags;
-#ifdef HAVE_OPEN64
- data->dev = open64(io->name, open_flags);
-#else
- data->dev = open(io->name, open_flags);
-#endif
+ data->dev = ext2fs_open_file(io->name, open_flags, 0);
if (data->dev < 0) {
retval = errno;
goto cleanup;
}
+ if (f_nocache) {
+ if (fcntl(data->dev, f_nocache, 1) < 0) {
+ retval = errno;
+ goto cleanup;
+ }
+ }
-#ifdef BLKSSZGET
- if (flags & IO_FLAG_DIRECT_IO) {
- if (ioctl(data->dev, BLKSSZGET, &data->align) != 0)
- data->align = io->block_size;
+ /*
+ * If the device is really a block device, then set the
+ * appropriate flag, otherwise we can set DISCARD_ZEROES flag
+ * because we are going to use punch hole instead of discard
+ * and if it succeed, subsequent read from sparse area returns
+ * zero.
+ */
+ if (ext2fs_stat(io->name, &st) == 0) {
+ if (S_ISBLK(st.st_mode))
+ io->flags |= CHANNEL_FLAGS_BLOCK_DEVICE;
+ else
+ io->flags |= CHANNEL_FLAGS_DISCARD_ZEROES;
+ }
+
+#ifdef BLKDISCARDZEROES
+ {
+ int zeroes = 0;
+ if (ioctl(data->dev, BLKDISCARDZEROES, &zeroes) == 0 &&
+ zeroes)
+ io->flags |= CHANNEL_FLAGS_DISCARD_ZEROES;
}
#endif
* Some operating systems require that the buffers be aligned,
* regardless of O_DIRECT
*/
- data->align = 512;
+ if (!io->align)
+ io->align = 512;
#endif
/* Is the block device actually writable? */
error = ioctl(data->dev, BLKROGET, &readonly);
if (!error && readonly) {
- close(data->dev);
retval = EPERM;
goto cleanup;
}
(ut.release[2] == '4') && (ut.release[3] == '.') &&
(ut.release[4] == '1') && (ut.release[5] >= '0') &&
(ut.release[5] < '8')) &&
- (fstat(data->dev, &st) == 0) &&
+ (ext2fs_stat(io->name, &st) == 0) &&
(S_ISBLK(st.st_mode))) {
struct rlimit rlim;
cleanup:
if (data) {
+ if (data->dev >= 0)
+ close(data->dev);
free_cache(data);
ext2fs_free_mem(&data);
}
- if (io)
+ if (io) {
+ if (io->name) {
+ ext2fs_free_mem(&io->name);
+ }
ext2fs_free_mem(&io);
+ }
return retval;
}
cache = reuse;
reuse_cache(channel, data, cache, block);
}
- memcpy(cache->buf, cp, channel->block_size);
+ if (cache->buf != cp)
+ memcpy(cache->buf, cp, channel->block_size);
cache->dirty = !writethrough;
count--;
block++;
#endif /* NO_IO_CACHE */
}
+static errcode_t unix_cache_readahead(io_channel channel,
+ unsigned long long block,
+ unsigned long long count)
+{
+#ifdef POSIX_FADV_WILLNEED
+ struct unix_private_data *data;
+
+ data = (struct unix_private_data *)channel->private_data;
+ return posix_fadvise(data->dev,
+ (ext2_loff_t)block * channel->block_size,
+ (ext2_loff_t)count * channel->block_size,
+ POSIX_FADV_WILLNEED);
+#else
+ return EXT2_ET_OP_NOT_SUPPORTED;
+#endif
+}
+
static errcode_t unix_write_blk(io_channel channel, unsigned long block,
int count, const void *buf)
{
data = (struct unix_private_data *) channel->private_data;
EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
- if (data->align != 0) {
+ if (channel->align != 0) {
#ifdef ALIGN_DEBUG
printf("unix_write_byte: O_DIRECT fallback\n");
#endif
}
return EXT2_ET_INVALID_ARGUMENT;
}
+
+#if defined(__linux__) && !defined(BLKDISCARD)
+#define BLKDISCARD _IO(0x12,119)
+#endif
+
+static errcode_t unix_discard(io_channel channel, unsigned long long block,
+ unsigned long long count)
+{
+ struct unix_private_data *data;
+ int ret;
+
+ EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
+ data = (struct unix_private_data *) channel->private_data;
+ EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
+
+ if (channel->flags & CHANNEL_FLAGS_BLOCK_DEVICE) {
+#ifdef BLKDISCARD
+ __u64 range[2];
+
+ range[0] = (__u64)(block) * channel->block_size;
+ range[1] = (__u64)(count) * channel->block_size;
+
+ ret = ioctl(data->dev, BLKDISCARD, &range);
+#else
+ goto unimplemented;
+#endif
+ } else {
+#if defined(HAVE_FALLOCATE) && defined(FALLOC_FL_PUNCH_HOLE)
+ /*
+ * If we are not on block device, try to use punch hole
+ * to reclaim free space.
+ */
+ ret = fallocate(data->dev,
+ FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ (off_t)(block) * channel->block_size,
+ (off_t)(count) * channel->block_size);
+#else
+ goto unimplemented;
+#endif
+ }
+ if (ret < 0) {
+ if (errno == EOPNOTSUPP)
+ goto unimplemented;
+ return errno;
+ }
+ return 0;
+unimplemented:
+ return EXT2_ET_UNIMPLEMENTED;
+}
+
+static errcode_t unix_zeroout(io_channel channel, unsigned long long block,
+ unsigned long long count)
+{
+ struct unix_private_data *data;
+ int ret;
+
+ EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
+ data = (struct unix_private_data *) channel->private_data;
+ EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
+
+ if (getenv("UNIX_IO_NOZEROOUT"))
+ goto unimplemented;
+
+ if (channel->flags & CHANNEL_FLAGS_BLOCK_DEVICE) {
+ /* Not implemented until the BLKZEROOUT mess is fixed */
+ goto unimplemented;
+ } else {
+ /* Regular file, try to use truncate/punch/zero. */
+#if defined(HAVE_FALLOCATE) && (defined(FALLOC_FL_ZERO_RANGE) || \
+ (defined(FALLOC_FL_PUNCH_HOLE) && defined(FALLOC_FL_KEEP_SIZE)))
+ struct stat statbuf;
+
+ if (count == 0)
+ return 0;
+ /*
+ * If we're trying to zero a range past the end of the file,
+ * extend the file size, then punch (or zero_range) everything.
+ */
+ ret = fstat(data->dev, &statbuf);
+ if (ret)
+ goto err;
+ if (statbuf.st_size < (block + count) * channel->block_size) {
+ ret = ftruncate(data->dev,
+ (block + count) * channel->block_size);
+ if (ret)
+ goto err;
+ }
+#if defined(FALLOC_FL_PUNCH_HOLE) && defined(FALLOC_FL_KEEP_SIZE)
+ ret = fallocate(data->dev,
+ FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ (off_t)(block) * channel->block_size,
+ (off_t)(count) * channel->block_size);
+ if (ret == 0)
+ goto err;
+#endif
+#ifdef FALLOC_FL_ZERO_RANGE
+ ret = fallocate(data->dev,
+ FALLOC_FL_ZERO_RANGE,
+ (off_t)(block) * channel->block_size,
+ (off_t)(count) * channel->block_size);
+#endif
+#else
+ goto unimplemented;
+#endif /* HAVE_FALLOCATE && (ZERO_RANGE || (PUNCH_HOLE && KEEP_SIZE)) */
+ }
+err:
+ if (ret < 0) {
+ if (errno == EOPNOTSUPP)
+ goto unimplemented;
+ return errno;
+ }
+ return 0;
+unimplemented:
+ return EXT2_ET_UNIMPLEMENTED;
+}
+
+static struct struct_io_manager struct_unix_manager = {
+ .magic = EXT2_ET_MAGIC_IO_MANAGER,
+ .name = "Unix I/O Manager",
+ .open = unix_open,
+ .close = unix_close,
+ .set_blksize = unix_set_blksize,
+ .read_blk = unix_read_blk,
+ .write_blk = unix_write_blk,
+ .flush = unix_flush,
+ .write_byte = unix_write_byte,
+ .set_option = unix_set_option,
+ .get_stats = unix_get_stats,
+ .read_blk64 = unix_read_blk64,
+ .write_blk64 = unix_write_blk64,
+ .discard = unix_discard,
+ .cache_readahead = unix_cache_readahead,
+ .zeroout = unix_zeroout,
+};
+
+io_manager unix_io_manager = &struct_unix_manager;