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-rw-r--r--lib/ext2fs/unix_io.c1510
1 files changed, 1510 insertions, 0 deletions
diff --git a/lib/ext2fs/unix_io.c b/lib/ext2fs/unix_io.c
new file mode 100644
index 0000000..3171c73
--- /dev/null
+++ b/lib/ext2fs/unix_io.c
@@ -0,0 +1,1510 @@
+/*
+ * unix_io.c --- This is the Unix (well, really POSIX) implementation
+ * 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.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Library
+ * General Public License, version 2.
+ * %End-Header%
+ */
+
+#if !defined(__FreeBSD__) && !defined(__NetBSD__) && !defined(__OpenBSD__)
+#define _XOPEN_SOURCE 600
+#define _DARWIN_C_SOURCE
+#define _FILE_OFFSET_BITS 64
+#ifndef _LARGEFILE_SOURCE
+#define _LARGEFILE_SOURCE
+#endif
+#ifndef _LARGEFILE64_SOURCE
+#define _LARGEFILE64_SOURCE
+#endif
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#endif
+
+#include "config.h"
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#if HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <fcntl.h>
+#include <time.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
+#ifdef HAVE_SYS_MOUNT_H
+#include <sys/mount.h>
+#endif
+#ifdef HAVE_SYS_PRCTL_H
+#include <sys/prctl.h>
+#else
+#define PR_GET_DUMPABLE 3
+#endif
+#if HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#if HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+#if HAVE_LINUX_FALLOC_H
+#include <linux/falloc.h>
+#endif
+#ifdef HAVE_PTHREAD
+#include <pthread.h>
+#endif
+
+#if defined(__linux__) && defined(_IO) && !defined(BLKROGET)
+#define BLKROGET _IO(0x12, 94) /* Get read-only status (0 = read_write). */
+#endif
+
+#undef ALIGN_DEBUG
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+#include "ext2fsP.h"
+
+/*
+ * For checking structure magic numbers...
+ */
+
+#define EXT2_CHECK_MAGIC(struct, code) \
+ if ((struct)->magic != (code)) return (code)
+
+struct unix_cache {
+ char *buf;
+ unsigned long long block;
+ int access_time;
+ unsigned dirty:1;
+ unsigned in_use:1;
+ unsigned write_err:1;
+};
+
+#define CACHE_SIZE 8
+#define WRITE_DIRECT_SIZE 4 /* Must be smaller than CACHE_SIZE */
+#define READ_DIRECT_SIZE 4 /* Should be smaller than CACHE_SIZE */
+
+struct unix_private_data {
+ int magic;
+ int dev;
+ int flags;
+ int align;
+ int access_time;
+ ext2_loff_t offset;
+ struct unix_cache cache[CACHE_SIZE];
+ void *bounce;
+ struct struct_io_stats io_stats;
+#ifdef HAVE_PTHREAD
+ pthread_mutex_t cache_mutex;
+ pthread_mutex_t bounce_mutex;
+ pthread_mutex_t stats_mutex;
+#endif
+};
+
+#define IS_ALIGNED(n, align) ((((uintptr_t) n) & \
+ ((uintptr_t) ((align)-1))) == 0)
+
+typedef enum lock_kind {
+ CACHE_MTX, BOUNCE_MTX, STATS_MTX
+} kind_t;
+
+#ifdef HAVE_PTHREAD
+static inline pthread_mutex_t *get_mutex(struct unix_private_data *data,
+ kind_t kind)
+{
+ if (data->flags & IO_FLAG_THREADS) {
+ switch (kind) {
+ case CACHE_MTX:
+ return &data->cache_mutex;
+ case BOUNCE_MTX:
+ return &data->bounce_mutex;
+ case STATS_MTX:
+ return &data->stats_mutex;
+ }
+ }
+ return NULL;
+}
+#endif
+
+static inline void mutex_lock(struct unix_private_data *data, kind_t kind)
+{
+#ifdef HAVE_PTHREAD
+ pthread_mutex_t *mtx = get_mutex(data,kind);
+
+ if (mtx)
+ pthread_mutex_lock(mtx);
+#endif
+}
+
+static inline void mutex_unlock(struct unix_private_data *data, kind_t kind)
+{
+#ifdef HAVE_PTHREAD
+ pthread_mutex_t *mtx = get_mutex(data,kind);
+
+ if (mtx)
+ pthread_mutex_unlock(mtx);
+#endif
+}
+
+static errcode_t unix_get_stats(io_channel channel, io_stats *stats)
+{
+ errcode_t retval = 0;
+
+ struct unix_private_data *data;
+
+ 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 (stats) {
+ mutex_lock(data, STATS_MTX);
+ *stats = &data->io_stats;
+ mutex_unlock(data, STATS_MTX);
+ }
+
+ return retval;
+}
+
+static char *safe_getenv(const char *arg)
+{
+ if ((getuid() != geteuid()) || (getgid() != getegid()))
+ return NULL;
+#ifdef HAVE_PRCTL
+ if (prctl(PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+ return NULL;
+#else
+#if (defined(linux) && defined(SYS_prctl))
+ if (syscall(SYS_prctl, PR_GET_DUMPABLE, 0, 0, 0, 0) == 0)
+ return NULL;
+#endif
+#endif
+
+#if defined(HAVE_SECURE_GETENV)
+ return secure_getenv(arg);
+#elif defined(HAVE___SECURE_GETENV)
+ return __secure_getenv(arg);
+#else
+ return getenv(arg);
+#endif
+}
+
+/*
+ * Here are the raw I/O functions
+ */
+static errcode_t raw_read_blk(io_channel channel,
+ struct unix_private_data *data,
+ unsigned long long block,
+ int count, void *bufv)
+{
+ errcode_t retval;
+ ssize_t size;
+ ext2_loff_t location;
+ int actual = 0;
+ unsigned char *buf = bufv;
+ ssize_t really_read = 0;
+ unsigned long long aligned_blk;
+ int align_size, offset;
+
+ size = (count < 0) ? -count : (ext2_loff_t) count * channel->block_size;
+ mutex_lock(data, STATS_MTX);
+ data->io_stats.bytes_read += size;
+ mutex_unlock(data, STATS_MTX);
+ location = ((ext2_loff_t) block * channel->block_size) + data->offset;
+
+ if (data->flags & IO_FLAG_FORCE_BOUNCE)
+ goto bounce_read;
+
+#ifdef HAVE_PREAD64
+ /* Try an aligned pread */
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(location, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
+ actual = pread64(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ actual = 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(location, channel->align) &&
+ IS_ALIGNED(size, channel->align)))) {
+ actual = pread(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ actual = 0;
+ }
+#endif /* HAVE_PREAD */
+
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(location, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
+ mutex_lock(data, BOUNCE_MTX);
+ if (ext2fs_llseek(data->dev, location, SEEK_SET) < 0) {
+ retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
+ goto error_unlock;
+ }
+ actual = read(data->dev, buf, size);
+ if (actual != size) {
+ short_read:
+ if (actual < 0) {
+ retval = errno;
+ actual = 0;
+ } else
+ retval = EXT2_ET_SHORT_READ;
+ goto error_unlock;
+ }
+ goto success_unlock;
+ }
+
+#ifdef ALIGN_DEBUG
+ printf("raw_read_blk: O_DIRECT fallback: %p %lu\n", buf,
+ (unsigned long) size);
+#endif
+
+ /*
+ * The buffer or size which we're trying to read isn't aligned
+ * to the O_DIRECT rules, so we need to do this the hard way...
+ */
+bounce_read:
+ if (channel->align == 0)
+ channel->align = 1;
+ if ((channel->block_size > channel->align) &&
+ (channel->block_size % channel->align) == 0)
+ align_size = channel->block_size;
+ else
+ align_size = channel->align;
+ aligned_blk = location / align_size;
+ offset = location % align_size;
+
+ mutex_lock(data, BOUNCE_MTX);
+ if (ext2fs_llseek(data->dev, aligned_blk * align_size, SEEK_SET) < 0) {
+ retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
+ goto error_unlock;
+ }
+ while (size > 0) {
+ actual = read(data->dev, data->bounce, align_size);
+ if (actual != align_size) {
+ actual = really_read;
+ buf -= really_read;
+ size += really_read;
+ goto short_read;
+ }
+ if ((actual + offset) > align_size)
+ actual = align_size - offset;
+ if (actual > size)
+ actual = size;
+ memcpy(buf, (char *)data->bounce + offset, actual);
+
+ really_read += actual;
+ size -= actual;
+ buf += actual;
+ offset = 0;
+ aligned_blk++;
+ }
+success_unlock:
+ mutex_unlock(data, BOUNCE_MTX);
+ return 0;
+
+error_unlock:
+ mutex_unlock(data, BOUNCE_MTX);
+ if (actual >= 0 && actual < size)
+ memset((char *) buf+actual, 0, size-actual);
+ if (channel->read_error)
+ retval = (channel->read_error)(channel, block, count, buf,
+ size, actual, retval);
+ return retval;
+}
+
+#define RAW_WRITE_NO_HANDLER 1
+
+static errcode_t raw_write_blk(io_channel channel,
+ struct unix_private_data *data,
+ unsigned long long block,
+ int count, const void *bufv,
+ int flags)
+{
+ ssize_t size;
+ ext2_loff_t location;
+ int actual = 0;
+ errcode_t retval;
+ const unsigned char *buf = bufv;
+ unsigned long long aligned_blk;
+ int align_size, offset;
+
+ if (count == 1)
+ size = channel->block_size;
+ else {
+ if (count < 0)
+ size = -count;
+ else
+ size = (ext2_loff_t) count * channel->block_size;
+ }
+ mutex_lock(data, STATS_MTX);
+ data->io_stats.bytes_written += size;
+ mutex_unlock(data, STATS_MTX);
+
+ location = ((ext2_loff_t) block * channel->block_size) + data->offset;
+
+ if (data->flags & IO_FLAG_FORCE_BOUNCE)
+ goto bounce_write;
+
+#ifdef HAVE_PWRITE64
+ /* Try an aligned pwrite */
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(location, 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(location, channel->align) &&
+ IS_ALIGNED(size, channel->align)))) {
+ actual = pwrite(data->dev, buf, size, location);
+ if (actual == size)
+ return 0;
+ }
+#endif /* HAVE_PWRITE */
+
+ if ((channel->align == 0) ||
+ (IS_ALIGNED(buf, channel->align) &&
+ IS_ALIGNED(location, channel->align) &&
+ IS_ALIGNED(size, channel->align))) {
+ mutex_lock(data, BOUNCE_MTX);
+ if (ext2fs_llseek(data->dev, location, SEEK_SET) < 0) {
+ retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
+ goto error_unlock;
+ }
+ actual = write(data->dev, buf, size);
+ mutex_unlock(data, BOUNCE_MTX);
+ if (actual < 0) {
+ retval = errno;
+ goto error_out;
+ }
+ if (actual != size) {
+ short_write:
+ retval = EXT2_ET_SHORT_WRITE;
+ goto error_out;
+ }
+ return 0;
+ }
+
+#ifdef ALIGN_DEBUG
+ printf("raw_write_blk: O_DIRECT fallback: %p %lu\n", buf,
+ (unsigned long) size);
+#endif
+ /*
+ * The buffer or size which we're trying to write isn't aligned
+ * to the O_DIRECT rules, so we need to do this the hard way...
+ */
+bounce_write:
+ if (channel->align == 0)
+ channel->align = 1;
+ if ((channel->block_size > channel->align) &&
+ (channel->block_size % channel->align) == 0)
+ align_size = channel->block_size;
+ else
+ align_size = channel->align;
+ aligned_blk = location / align_size;
+ offset = location % align_size;
+
+ while (size > 0) {
+ int actual_w;
+
+ mutex_lock(data, BOUNCE_MTX);
+ if (size < align_size || offset) {
+ if (ext2fs_llseek(data->dev, aligned_blk * align_size,
+ SEEK_SET) < 0) {
+ retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
+ goto error_unlock;
+ }
+ actual = read(data->dev, data->bounce,
+ align_size);
+ if (actual != align_size) {
+ if (actual < 0) {
+ retval = errno;
+ goto error_unlock;
+ }
+ memset((char *) data->bounce + actual, 0,
+ align_size - actual);
+ }
+ }
+ actual = size;
+ if ((actual + offset) > align_size)
+ actual = align_size - offset;
+ if (actual > size)
+ actual = size;
+ memcpy(((char *)data->bounce) + offset, buf, actual);
+ if (ext2fs_llseek(data->dev, aligned_blk * align_size, SEEK_SET) < 0) {
+ retval = errno ? errno : EXT2_ET_LLSEEK_FAILED;
+ goto error_unlock;
+ }
+ actual_w = write(data->dev, data->bounce, align_size);
+ mutex_unlock(data, BOUNCE_MTX);
+ if (actual_w < 0) {
+ retval = errno;
+ goto error_out;
+ }
+ if (actual_w != align_size)
+ goto short_write;
+ size -= actual;
+ buf += actual;
+ location += actual;
+ aligned_blk++;
+ offset = 0;
+ }
+ return 0;
+
+error_unlock:
+ mutex_unlock(data, BOUNCE_MTX);
+error_out:
+ if (((flags & RAW_WRITE_NO_HANDLER) == 0) && channel->write_error)
+ retval = (channel->write_error)(channel, block, count, buf,
+ size, actual, retval);
+ return retval;
+}
+
+
+/*
+ * Here we implement the cache functions
+ */
+
+/* Allocate the cache buffers */
+static errcode_t alloc_cache(io_channel channel,
+ struct unix_private_data *data)
+{
+ errcode_t retval;
+ struct unix_cache *cache;
+ int i;
+
+ data->access_time = 0;
+ for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
+ cache->block = 0;
+ cache->access_time = 0;
+ cache->dirty = 0;
+ cache->in_use = 0;
+ if (cache->buf)
+ ext2fs_free_mem(&cache->buf);
+ retval = io_channel_alloc_buf(channel, 0, &cache->buf);
+ if (retval)
+ return retval;
+ }
+ if (channel->align || data->flags & IO_FLAG_FORCE_BOUNCE) {
+ if (data->bounce)
+ ext2fs_free_mem(&data->bounce);
+ retval = io_channel_alloc_buf(channel, 0, &data->bounce);
+ }
+ return retval;
+}
+
+/* Free the cache buffers */
+static void free_cache(struct unix_private_data *data)
+{
+ struct unix_cache *cache;
+ int i;
+
+ data->access_time = 0;
+ for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
+ cache->block = 0;
+ cache->access_time = 0;
+ cache->dirty = 0;
+ cache->in_use = 0;
+ if (cache->buf)
+ ext2fs_free_mem(&cache->buf);
+ }
+ if (data->bounce)
+ ext2fs_free_mem(&data->bounce);
+}
+
+#ifndef NO_IO_CACHE
+/*
+ * Try to find a block in the cache. If the block is not found, and
+ * eldest is a non-zero pointer, then fill in eldest with the cache
+ * entry to that should be reused.
+ */
+static struct unix_cache *find_cached_block(struct unix_private_data *data,
+ unsigned long long block,
+ struct unix_cache **eldest)
+{
+ struct unix_cache *cache, *unused_cache, *oldest_cache;
+ int i;
+
+ unused_cache = oldest_cache = 0;
+ for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
+ if (!cache->in_use) {
+ if (!unused_cache)
+ unused_cache = cache;
+ continue;
+ }
+ if (cache->block == block) {
+ cache->access_time = ++data->access_time;
+ return cache;
+ }
+ if (!oldest_cache ||
+ (cache->access_time < oldest_cache->access_time))
+ oldest_cache = cache;
+ }
+ if (eldest)
+ *eldest = (unused_cache) ? unused_cache : oldest_cache;
+ return 0;
+}
+
+/*
+ * Reuse a particular cache entry for another block.
+ */
+static errcode_t reuse_cache(io_channel channel,
+ struct unix_private_data *data, struct unix_cache *cache,
+ unsigned long long block)
+{
+ if (cache->dirty && cache->in_use) {
+ errcode_t retval;
+
+ retval = raw_write_blk(channel, data, cache->block, 1,
+ cache->buf, RAW_WRITE_NO_HANDLER);
+ if (retval) {
+ cache->write_err = 1;
+ return retval;
+ }
+ }
+
+ cache->in_use = 1;
+ cache->dirty = 0;
+ cache->write_err = 0;
+ cache->block = block;
+ cache->access_time = ++data->access_time;
+ return 0;
+}
+
+#define FLUSH_INVALIDATE 0x01
+#define FLUSH_NOLOCK 0x02
+
+/*
+ * Flush all of the blocks in the cache
+ */
+static errcode_t flush_cached_blocks(io_channel channel,
+ struct unix_private_data *data,
+ int flags)
+{
+ struct unix_cache *cache;
+ errcode_t retval, retval2 = 0;
+ int i;
+ int errors_found = 0;
+
+ if ((flags & FLUSH_NOLOCK) == 0)
+ mutex_lock(data, CACHE_MTX);
+ for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
+ if (!cache->in_use || !cache->dirty)
+ continue;
+ retval = raw_write_blk(channel, data,
+ cache->block, 1, cache->buf,
+ RAW_WRITE_NO_HANDLER);
+ if (retval) {
+ cache->write_err = 1;
+ errors_found = 1;
+ retval2 = retval;
+ } else {
+ cache->dirty = 0;
+ cache->write_err = 0;
+ if (flags & FLUSH_INVALIDATE)
+ cache->in_use = 0;
+ }
+ }
+ if ((flags & FLUSH_NOLOCK) == 0)
+ mutex_unlock(data, CACHE_MTX);
+retry:
+ while (errors_found) {
+ if ((flags & FLUSH_NOLOCK) == 0)
+ mutex_lock(data, CACHE_MTX);
+ errors_found = 0;
+ for (i=0, cache = data->cache; i < CACHE_SIZE; i++, cache++) {
+ if (!cache->in_use || !cache->write_err)
+ continue;
+ errors_found = 1;
+ if (cache->write_err && channel->write_error) {
+ char *err_buf = NULL;
+ unsigned long long err_block = cache->block;
+
+ cache->dirty = 0;
+ cache->in_use = 0;
+ cache->write_err = 0;
+ if (io_channel_alloc_buf(channel, 0,
+ &err_buf))
+ err_buf = NULL;
+ else
+ memcpy(err_buf, cache->buf,
+ channel->block_size);
+ mutex_unlock(data, CACHE_MTX);
+ (channel->write_error)(channel, err_block,
+ 1, err_buf, channel->block_size, -1,
+ retval2);
+ if (err_buf)
+ ext2fs_free_mem(&err_buf);
+ goto retry;
+ } else
+ cache->write_err = 0;
+ }
+ if ((flags & FLUSH_NOLOCK) == 0)
+ mutex_unlock(data, CACHE_MTX);
+ }
+ return retval2;
+}
+#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_channel(const char *name, int fd,
+ int flags, io_channel *channel,
+ io_manager io_mgr)
+{
+ io_channel io = NULL;
+ struct unix_private_data *data = NULL;
+ errcode_t retval;
+ ext2fs_struct_stat st;
+#ifdef __linux__
+ struct utsname ut;
+#endif
+
+ if (safe_getenv("UNIX_IO_FORCE_BOUNCE"))
+ flags |= IO_FLAG_FORCE_BOUNCE;
+
+#ifdef __linux__
+ /*
+ * We need to make sure any previous errors in the block
+ * device are thrown away, sigh.
+ */
+ (void) fsync(fd);
+#endif
+
+ retval = ext2fs_get_mem(sizeof(struct struct_io_channel), &io);
+ if (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);
+ if (retval)
+ goto cleanup;
+
+ io->manager = io_mgr;
+ retval = ext2fs_get_mem(strlen(name)+1, &io->name);
+ if (retval)
+ goto cleanup;
+
+ strcpy(io->name, name);
+ io->private_data = data;
+ io->block_size = 1024;
+ io->read_error = 0;
+ io->write_error = 0;
+ io->refcount = 1;
+ io->flags = 0;
+
+ memset(data, 0, sizeof(struct unix_private_data));
+ data->magic = EXT2_ET_MAGIC_UNIX_IO_CHANNEL;
+ data->io_stats.num_fields = 2;
+ data->flags = flags;
+ data->dev = fd;
+
+#if defined(O_DIRECT)
+ if (flags & IO_FLAG_DIRECT_IO)
+ io->align = ext2fs_get_dio_alignment(data->dev);
+#elif defined(F_NOCACHE)
+ if (flags & IO_FLAG_DIRECT_IO)
+ io->align = 4096;
+#endif
+
+ /*
+ * 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_fstat(data->dev, &st) == 0) {
+ if (ext2fsP_is_disk_device(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
+
+#if defined(__CYGWIN__)
+ /*
+ * Some operating systems require that the buffers be aligned,
+ * regardless of O_DIRECT
+ */
+ if (!io->align)
+ io->align = 512;
+#endif
+
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+ if (io->flags & CHANNEL_FLAGS_BLOCK_DEVICE) {
+ int dio_align = ext2fs_get_dio_alignment(fd);
+
+ if (io->align < dio_align)
+ io->align = dio_align;
+ }
+#endif
+
+ if ((retval = alloc_cache(io, data)))
+ goto cleanup;
+
+#ifdef BLKROGET
+ if (flags & IO_FLAG_RW) {
+ int error;
+ int readonly = 0;
+
+ /* Is the block device actually writable? */
+ error = ioctl(data->dev, BLKROGET, &readonly);
+ if (!error && readonly) {
+ retval = EPERM;
+ goto cleanup;
+ }
+ }
+#endif
+
+#ifdef __linux__
+#undef RLIM_INFINITY
+#if (defined(__alpha__) || ((defined(__sparc__) || defined(__mips__)) && (SIZEOF_LONG == 4)))
+#define RLIM_INFINITY ((unsigned long)(~0UL>>1))
+#else
+#define RLIM_INFINITY (~0UL)
+#endif
+ /*
+ * Work around a bug in 2.4.10-2.4.18 kernels where writes to
+ * block devices are wrongly getting hit by the filesize
+ * limit. This workaround isn't perfect, since it won't work
+ * if glibc wasn't built against 2.2 header files. (Sigh.)
+ *
+ */
+ if ((flags & IO_FLAG_RW) &&
+ (uname(&ut) == 0) &&
+ ((ut.release[0] == '2') && (ut.release[1] == '.') &&
+ (ut.release[2] == '4') && (ut.release[3] == '.') &&
+ (ut.release[4] == '1') && (ut.release[5] >= '0') &&
+ (ut.release[5] < '8')) &&
+ (ext2fs_fstat(data->dev, &st) == 0) &&
+ (ext2fsP_is_disk_device(st.st_mode))) {
+ struct rlimit rlim;
+
+ rlim.rlim_cur = rlim.rlim_max = (unsigned long) RLIM_INFINITY;
+ setrlimit(RLIMIT_FSIZE, &rlim);
+ getrlimit(RLIMIT_FSIZE, &rlim);
+ if (((unsigned long) rlim.rlim_cur) <
+ ((unsigned long) rlim.rlim_max)) {
+ rlim.rlim_cur = rlim.rlim_max;
+ setrlimit(RLIMIT_FSIZE, &rlim);
+ }
+ }
+#endif
+#ifdef HAVE_PTHREAD
+ if (flags & IO_FLAG_THREADS) {
+ io->flags |= CHANNEL_FLAGS_THREADS;
+ retval = pthread_mutex_init(&data->cache_mutex, NULL);
+ if (retval)
+ goto cleanup;
+ retval = pthread_mutex_init(&data->bounce_mutex, NULL);
+ if (retval) {
+ pthread_mutex_destroy(&data->cache_mutex);
+ goto cleanup;
+ }
+ retval = pthread_mutex_init(&data->stats_mutex, NULL);
+ if (retval) {
+ pthread_mutex_destroy(&data->cache_mutex);
+ pthread_mutex_destroy(&data->bounce_mutex);
+ goto cleanup;
+ }
+ }
+#endif
+ *channel = io;
+ return 0;
+
+cleanup:
+ if (data) {
+ if (data->dev >= 0)
+ close(data->dev);
+ free_cache(data);
+ ext2fs_free_mem(&data);
+ }
+ if (io) {
+ if (io->name) {
+ ext2fs_free_mem(&io->name);
+ }
+ ext2fs_free_mem(&io);
+ }
+ return retval;
+}
+
+static errcode_t unixfd_open(const char *str_fd, int flags,
+ io_channel *channel)
+{
+ int fd;
+ int fd_flags;
+
+ fd = atoi(str_fd);
+#if defined(HAVE_FCNTL)
+ fd_flags = fcntl(fd, F_GETFD);
+ if (fd_flags == -1)
+ return EBADF;
+
+ flags = 0;
+ if (fd_flags & O_RDWR)
+ flags |= IO_FLAG_RW;
+ if (fd_flags & O_EXCL)
+ flags |= IO_FLAG_EXCLUSIVE;
+#if defined(O_DIRECT)
+ if (fd_flags & O_DIRECT)
+ flags |= IO_FLAG_DIRECT_IO;
+#endif
+#endif /* HAVE_FCNTL */
+
+ return unix_open_channel(str_fd, fd, flags, channel, unixfd_io_manager);
+}
+
+static errcode_t unix_open(const char *name, int flags,
+ io_channel *channel)
+{
+ int fd = -1;
+ int open_flags;
+
+ if (name == 0)
+ return EXT2_ET_BAD_DEVICE_NAME;
+
+ open_flags = (flags & IO_FLAG_RW) ? O_RDWR : O_RDONLY;
+ if (flags & IO_FLAG_EXCLUSIVE)
+ open_flags |= O_EXCL;
+#if defined(O_DIRECT)
+ if (flags & IO_FLAG_DIRECT_IO)
+ open_flags |= O_DIRECT;
+#endif
+ fd = ext2fs_open_file(name, open_flags, 0);
+ if (fd < 0)
+ return errno;
+#if defined(F_NOCACHE) && !defined(IO_DIRECT)
+ if (flags & IO_FLAG_DIRECT_IO) {
+ if (fcntl(fd, F_NOCACHE, 1) < 0)
+ return errno;
+ }
+#endif
+ return unix_open_channel(name, fd, flags, channel, unix_io_manager);
+}
+
+static errcode_t unix_close(io_channel channel)
+{
+ struct unix_private_data *data;
+ errcode_t retval = 0;
+
+ 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->refcount > 0)
+ return 0;
+
+#ifndef NO_IO_CACHE
+ retval = flush_cached_blocks(channel, data, 0);
+#endif
+
+ if (close(data->dev) < 0)
+ retval = errno;
+ free_cache(data);
+#ifdef HAVE_PTHREAD
+ if (data->flags & IO_FLAG_THREADS) {
+ pthread_mutex_destroy(&data->cache_mutex);
+ pthread_mutex_destroy(&data->bounce_mutex);
+ pthread_mutex_destroy(&data->stats_mutex);
+ }
+#endif
+
+ ext2fs_free_mem(&channel->private_data);
+ if (channel->name)
+ ext2fs_free_mem(&channel->name);
+ ext2fs_free_mem(&channel);
+ return retval;
+}
+
+static errcode_t unix_set_blksize(io_channel channel, int blksize)
+{
+ struct unix_private_data *data;
+ errcode_t retval = 0;
+
+ 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->block_size != blksize) {
+ mutex_lock(data, CACHE_MTX);
+ mutex_lock(data, BOUNCE_MTX);
+#ifndef NO_IO_CACHE
+ if ((retval = flush_cached_blocks(channel, data, FLUSH_NOLOCK))){
+ mutex_unlock(data, BOUNCE_MTX);
+ mutex_unlock(data, CACHE_MTX);
+ return retval;
+ }
+#endif
+
+ channel->block_size = blksize;
+ free_cache(data);
+ retval = alloc_cache(channel, data);
+ mutex_unlock(data, BOUNCE_MTX);
+ mutex_unlock(data, CACHE_MTX);
+ }
+ return retval;
+}
+
+static errcode_t unix_read_blk64(io_channel channel, unsigned long long block,
+ int count, void *buf)
+{
+ struct unix_private_data *data;
+ struct unix_cache *cache;
+ errcode_t retval;
+ char *cp;
+ int i, j;
+
+ 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);
+
+#ifdef NO_IO_CACHE
+ return raw_read_blk(channel, data, block, count, buf);
+#else
+ if (data->flags & IO_FLAG_NOCACHE)
+ return raw_read_blk(channel, data, block, count, buf);
+ /*
+ * If we're doing an odd-sized read or a very large read,
+ * flush out the cache and then do a direct read.
+ */
+ if (count < 0 || count > WRITE_DIRECT_SIZE) {
+ if ((retval = flush_cached_blocks(channel, data, 0)))
+ return retval;
+ return raw_read_blk(channel, data, block, count, buf);
+ }
+
+ cp = buf;
+ mutex_lock(data, CACHE_MTX);
+ while (count > 0) {
+ /* If it's in the cache, use it! */
+ if ((cache = find_cached_block(data, block, NULL))) {
+#ifdef DEBUG
+ printf("Using cached block %lu\n", block);
+#endif
+ memcpy(cp, cache->buf, channel->block_size);
+ count--;
+ block++;
+ cp += channel->block_size;
+ continue;
+ }
+
+ /*
+ * Find the number of uncached blocks so we can do a
+ * single read request
+ */
+ for (i=1; i < count; i++)
+ if (find_cached_block(data, block+i, NULL))
+ break;
+#ifdef DEBUG
+ printf("Reading %d blocks starting at %lu\n", i, block);
+#endif
+ mutex_unlock(data, CACHE_MTX);
+ if ((retval = raw_read_blk(channel, data, block, i, cp)))
+ return retval;
+ mutex_lock(data, CACHE_MTX);
+
+ /* Save the results in the cache */
+ for (j=0; j < i; j++) {
+ if (!find_cached_block(data, block, &cache)) {
+ retval = reuse_cache(channel, data,
+ cache, block);
+ if (retval)
+ goto call_write_handler;
+ memcpy(cache->buf, cp, channel->block_size);
+ }
+ count--;
+ block++;
+ cp += channel->block_size;
+ }
+ }
+ mutex_unlock(data, CACHE_MTX);
+ return 0;
+
+call_write_handler:
+ if (cache->write_err && channel->write_error) {
+ char *err_buf = NULL;
+ unsigned long long err_block = cache->block;
+
+ cache->dirty = 0;
+ cache->in_use = 0;
+ cache->write_err = 0;
+ if (io_channel_alloc_buf(channel, 0, &err_buf))
+ err_buf = NULL;
+ else
+ memcpy(err_buf, cache->buf, channel->block_size);
+ mutex_unlock(data, CACHE_MTX);
+ (channel->write_error)(channel, err_block, 1, err_buf,
+ channel->block_size, -1,
+ retval);
+ if (err_buf)
+ ext2fs_free_mem(&err_buf);
+ } else
+ mutex_unlock(data, CACHE_MTX);
+ return retval;
+#endif /* NO_IO_CACHE */
+}
+
+static errcode_t unix_read_blk(io_channel channel, unsigned long block,
+ int count, void *buf)
+{
+ return unix_read_blk64(channel, block, count, buf);
+}
+
+static errcode_t unix_write_blk64(io_channel channel, unsigned long long block,
+ int count, const void *buf)
+{
+ struct unix_private_data *data;
+ struct unix_cache *cache, *reuse;
+ errcode_t retval = 0;
+ const char *cp;
+ int writethrough;
+
+ 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);
+
+#ifdef NO_IO_CACHE
+ return raw_write_blk(channel, data, block, count, buf, 0);
+#else
+ if (data->flags & IO_FLAG_NOCACHE)
+ return raw_write_blk(channel, data, block, count, buf, 0);
+ /*
+ * If we're doing an odd-sized write or a very large write,
+ * flush out the cache completely and then do a direct write.
+ */
+ if (count < 0 || count > WRITE_DIRECT_SIZE) {
+ if ((retval = flush_cached_blocks(channel, data,
+ FLUSH_INVALIDATE)))
+ return retval;
+ return raw_write_blk(channel, data, block, count, buf, 0);
+ }
+
+ /*
+ * For a moderate-sized multi-block write, first force a write
+ * if we're in write-through cache mode, and then fill the
+ * cache with the blocks.
+ */
+ writethrough = channel->flags & CHANNEL_FLAGS_WRITETHROUGH;
+ if (writethrough)
+ retval = raw_write_blk(channel, data, block, count, buf, 0);
+
+ cp = buf;
+ mutex_lock(data, CACHE_MTX);
+ while (count > 0) {
+ cache = find_cached_block(data, block, &reuse);
+ if (!cache) {
+ errcode_t err;
+
+ cache = reuse;
+ err = reuse_cache(channel, data, cache, block);
+ if (err)
+ goto call_write_handler;
+ }
+ if (cache->buf != cp)
+ memcpy(cache->buf, cp, channel->block_size);
+ cache->dirty = !writethrough;
+ count--;
+ block++;
+ cp += channel->block_size;
+ }
+ mutex_unlock(data, CACHE_MTX);
+ return retval;
+
+call_write_handler:
+ if (cache->write_err && channel->write_error) {
+ char *err_buf = NULL;
+ unsigned long long err_block = cache->block;
+
+ cache->dirty = 0;
+ cache->in_use = 0;
+ cache->write_err = 0;
+ if (io_channel_alloc_buf(channel, 0, &err_buf))
+ err_buf = NULL;
+ else
+ memcpy(err_buf, cache->buf, channel->block_size);
+ mutex_unlock(data, CACHE_MTX);
+ (channel->write_error)(channel, err_block, 1, err_buf,
+ channel->block_size, -1,
+ retval);
+ if (err_buf)
+ ext2fs_free_mem(&err_buf);
+ } else
+ mutex_unlock(data, CACHE_MTX);
+ return retval;
+#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;
+ EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
+ return posix_fadvise(data->dev,
+ (ext2_loff_t)block * channel->block_size + data->offset,
+ (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)
+{
+ return unix_write_blk64(channel, block, count, buf);
+}
+
+static errcode_t unix_write_byte(io_channel channel, unsigned long offset,
+ int size, const void *buf)
+{
+ struct unix_private_data *data;
+ errcode_t retval = 0;
+ ssize_t actual;
+
+ 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->align != 0) {
+#ifdef ALIGN_DEBUG
+ printf("unix_write_byte: O_DIRECT fallback\n");
+#endif
+ return EXT2_ET_UNIMPLEMENTED;
+ }
+
+#ifndef NO_IO_CACHE
+ /*
+ * Flush out the cache completely
+ */
+ if ((retval = flush_cached_blocks(channel, data, FLUSH_INVALIDATE)))
+ return retval;
+#endif
+
+ if (lseek(data->dev, offset + data->offset, SEEK_SET) < 0)
+ return errno;
+
+ actual = write(data->dev, buf, size);
+ if (actual < 0)
+ return errno;
+ if (actual != size)
+ return EXT2_ET_SHORT_WRITE;
+
+ return 0;
+}
+
+/*
+ * Flush data buffers to disk.
+ */
+static errcode_t unix_flush(io_channel channel)
+{
+ struct unix_private_data *data;
+ errcode_t retval = 0;
+
+ 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);
+
+#ifndef NO_IO_CACHE
+ retval = flush_cached_blocks(channel, data, 0);
+#endif
+#ifdef HAVE_FSYNC
+ if (!retval && fsync(data->dev) != 0)
+ return errno;
+#endif
+ return retval;
+}
+
+static errcode_t unix_set_option(io_channel channel, const char *option,
+ const char *arg)
+{
+ struct unix_private_data *data;
+ unsigned long long tmp;
+ errcode_t retval;
+ char *end;
+
+ 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 (!strcmp(option, "offset")) {
+ if (!arg)
+ return EXT2_ET_INVALID_ARGUMENT;
+
+ tmp = strtoull(arg, &end, 0);
+ if (*end)
+ return EXT2_ET_INVALID_ARGUMENT;
+ data->offset = tmp;
+ if (data->offset < 0)
+ return EXT2_ET_INVALID_ARGUMENT;
+ return 0;
+ }
+ if (!strcmp(option, "cache")) {
+ if (!arg)
+ return EXT2_ET_INVALID_ARGUMENT;
+ if (!strcmp(arg, "on")) {
+ data->flags &= ~IO_FLAG_NOCACHE;
+ return 0;
+ }
+ if (!strcmp(arg, "off")) {
+ retval = flush_cached_blocks(channel, data, 0);
+ data->flags |= IO_FLAG_NOCACHE;
+ return retval;
+ }
+ return EXT2_ET_INVALID_ARGUMENT;
+ }
+ 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 + data->offset;
+ 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 + data->offset,
+ (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;
+}
+
+/*
+ * If we know about ZERO_RANGE, try that before we try PUNCH_HOLE because
+ * ZERO_RANGE doesn't unmap preallocated blocks. We prefer fallocate because
+ * it always invalidates page cache, and libext2fs requires that reads after
+ * ZERO_RANGE return zeroes.
+ */
+static int __unix_zeroout(int fd, off_t offset, off_t len)
+{
+ int ret = -1;
+
+#if defined(HAVE_FALLOCATE) && defined(FALLOC_FL_ZERO_RANGE)
+ ret = fallocate(fd, FALLOC_FL_ZERO_RANGE, offset, len);
+ if (ret == 0)
+ return 0;
+#endif
+#if defined(HAVE_FALLOCATE) && defined(FALLOC_FL_PUNCH_HOLE) && defined(FALLOC_FL_KEEP_SIZE)
+ ret = fallocate(fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
+ offset, len);
+ if (ret == 0)
+ return 0;
+#endif
+ errno = EOPNOTSUPP;
+ return ret;
+}
+
+/* parameters might not be used if OS doesn't support zeroout */
+#if __GNUC_PREREQ (4, 6)
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+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 (safe_getenv("UNIX_IO_NOZEROOUT"))
+ goto unimplemented;
+
+ if (!(channel->flags & CHANNEL_FLAGS_BLOCK_DEVICE)) {
+ /* Regular file, try to use truncate/punch/zero. */
+ 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 truncate everything.
+ */
+ ret = fstat(data->dev, &statbuf);
+ if (ret)
+ goto err;
+ if ((unsigned long long) statbuf.st_size <
+ (block + count) * channel->block_size + data->offset) {
+ ret = ftruncate(data->dev,
+ (block + count) * channel->block_size + data->offset);
+ if (ret)
+ goto err;
+ }
+ }
+
+ ret = __unix_zeroout(data->dev,
+ (off_t)(block) * channel->block_size + data->offset,
+ (off_t)(count) * channel->block_size);
+err:
+ if (ret < 0) {
+ if (errno == EOPNOTSUPP)
+ goto unimplemented;
+ return errno;
+ }
+ return 0;
+unimplemented:
+ return EXT2_ET_UNIMPLEMENTED;
+}
+#if __GNUC_PREREQ (4, 6)
+#pragma GCC diagnostic pop
+#endif
+
+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;
+
+static struct struct_io_manager struct_unixfd_manager = {
+ .magic = EXT2_ET_MAGIC_IO_MANAGER,
+ .name = "Unix fd I/O Manager",
+ .open = unixfd_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 unixfd_io_manager = &struct_unixfd_manager;
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-04 12:12:52 +0000