snapraid/cmdline/parity.c

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2019-01-07 14:06:15 +01:00
/*
* Copyright (C) 2011 Andrea Mazzoleni
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "portable.h"
#include "support.h"
#include "elem.h"
#include "state.h"
#include "parity.h"
#include "handle.h"
/**
* Pseudo random limits for parity
*/
#define PARITY_LIMIT(size, split, level) \
size ? size + (123562341 + split * 634542351 + level * 983491341) % size : 0
/****************************************************************************/
/* parity */
block_off_t parity_allocated_size(struct snapraid_state* state)
{
block_off_t parity_block;
tommy_node* i;
/* compute the size of the parity file */
parity_block = 0;
for (i = state->disklist; i != 0; i = i->next) {
struct snapraid_disk* disk = i->data;
/* start from the declared size */
block_off_t block = fs_size(disk);
/* decrease the block until an allocated one, but part of a file */
/* we don't stop at deleted blocks, because we want to have them cleared */
/* if they are at the end of the parity */
while (block > parity_block && !block_has_file(fs_par2block_find(disk, block - 1)))
--block;
/* get the highest value */
if (block > parity_block)
parity_block = block;
}
return parity_block;
}
block_off_t parity_used_size(struct snapraid_state* state)
{
block_off_t parity_block;
tommy_node* i;
/* compute the size of the parity file */
parity_block = 0;
for (i = state->disklist; i != 0; i = i->next) {
struct snapraid_disk* disk = i->data;
/* start from the declared size */
block_off_t block = fs_size(disk);
/* decrease the block until an used one */
while (block > parity_block && !block_has_file_and_valid_parity(fs_par2block_find(disk, block - 1)))
--block;
/* get the highest value */
if (block > parity_block)
parity_block = block;
}
return parity_block;
}
int parity_is_invalid(struct snapraid_state* state)
{
block_off_t blockmax;
block_off_t i;
blockmax = parity_allocated_size(state);
for (i = 0; i < blockmax; ++i) {
tommy_node* node_disk;
int one_invalid;
int one_valid;
/* for each disk */
one_invalid = 0;
one_valid = 0;
for (node_disk = state->disklist; node_disk != 0; node_disk = node_disk->next) {
struct snapraid_disk* disk = node_disk->data;
struct snapraid_block* block = fs_par2block_find(disk, i);
if (block_has_file(block))
one_valid = 1;
if (block_has_invalid_parity(block))
one_invalid = 1;
}
/* if both valid and invalid, we need to update */
if (one_invalid && one_valid)
return 1;
}
return 0;
}
void parity_overflow(struct snapraid_state* state, data_off_t size)
{
tommy_node* i;
block_off_t blockalloc;
int found = 0;
char esc_buffer[ESC_MAX];
/* don't report if everything is outside or if the file is not accessible */
if (size == 0) {
return;
}
blockalloc = size / state->block_size;
/* for all disks */
for (i = state->disklist; i != 0; i = i->next) {
struct snapraid_disk* disk = i->data;
tommy_node* j;
/* for all files */
for (j = disk->filelist; j != 0; j = j->next) {
struct snapraid_file* file = j->data;
if (file->blockmax > 0) {
block_off_t parity_pos = fs_file2par_get(disk, file, file->blockmax - 1);
if (parity_pos >= blockalloc) {
found = 1;
log_tag("outofparity:%s:%s\n", disk->name, esc_tag(file->sub, esc_buffer));
log_fatal("outofparity %s%s\n", disk->dir, file->sub);
}
}
}
}
if (found) {
log_fatal("\nYour data requires more parity than the available space.\n");
log_fatal("Please move the files 'outofparity' to another data disk.\n");
}
}
void parity_size(struct snapraid_parity_handle* handle, data_off_t* out_size)
{
unsigned s;
data_off_t size;
/* now compute the size summing all the parity splits */
size = 0;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
size += split->size;
}
*out_size = size;
}
int parity_create(struct snapraid_parity_handle* handle, const struct snapraid_parity* parity, unsigned level, int mode, uint32_t block_size, data_off_t limit_size)
{
unsigned s;
data_off_t block_mask;
/* mask of bits used by the block size */
block_mask = ((data_off_t)block_size) - 1;
handle->level = level;
handle->split_mac = 0;
for (s = 0; s < parity->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int ret;
int flags;
advise_init(&split->advise, mode);
pathcpy(split->path, sizeof(split->path), parity->split_map[s].path);
split->size = parity->split_map[s].size;
split->limit_size = PARITY_LIMIT(limit_size, s, level);
/* opening in sequential mode in Windows */
flags = O_RDWR | O_CREAT | O_BINARY | advise_flags(&split->advise);
split->f = open(split->path, flags, 0600);
if (split->f == -1) {
/* LCOV_EXCL_START */
log_fatal("Error opening parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
/* we have a valid file handle */
++handle->split_mac;
/* get the stat info */
ret = fstat(split->f, &split->st);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error accessing parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
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/* the initial valid size is the size on disk */
split->valid_size = split->st.st_size;
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/**
* If the parity size is not yet set, set it now.
* This happens when expanding the number of parities,
* or when upgrading from a content file that has not split->size data.
*/
if (split->size == PARITY_SIZE_INVALID) {
split->size = split->st.st_size;
/* ensure that the resulting size if block aligned */
if ((split->size & block_mask) != 0) {
/* LCOV_EXCL_START */
log_fatal("Error in preallocated size of parity file '%s' with size %" PRIu64 " and block %u .\n", split->path, split->size, block_size);
goto bail;
/* LCOV_EXCL_STOP */
}
}
ret = advise_open(&split->advise, split->f);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error advising parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
}
return 0;
bail:
/* LCOV_EXCL_START */
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
close(split->f);
split->f = -1;
}
return -1;
/* LCOV_EXCL_STOP */
}
static int parity_handle_grow(struct snapraid_split_handle* split, data_off_t previous_size, data_off_t size, int skip_fallocate)
{
int ret;
(void)previous_size;
/* simulate a failure for testing limits */
if (split->limit_size != 0 && size > (data_off_t)split->limit_size)
return -1;
#if HAVE_FALLOCATE
if (!skip_fallocate) {
/*
* Allocate real space using the specific Linux fallocate() operation.
* If the underline file-system doesn't support it, this operation fails.
*
* Instead posix_fallocate() fallbacks to write the whole file,
* and we cannot use it as we may need to initialize a multi terabyte
* file.
*
* See: fallocate vs posix_fallocate
* http://stackoverflow.com/questions/14063046/fallocate-vs-posix-fallocate
*
* To work better with Btrfs, use as offset the previous allocated size.
* Otherwise Btrfs will count as space needed even the already allocated one.
*
* See: Massive loss of disk space
* https://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg66454.html
*/
ret = fallocate(split->f, 0, previous_size, size - previous_size);
/*
* In some legacy system fallocate() may return the error number
* as positive integer, and in this case it doesn't set errno.
*
* Detect and handle this case.
*
* See: Fix fallocate error return on i386
* https://sourceware.org/ml/libc-hacker/2010-04/msg00000.html
*
* See: [PATCH XFS] Fix error return for fallocate() on XFS
* http://oss.sgi.com/archives/xfs/2009-11/msg00201.html
*/
if (ret > 0) {
/* LCOV_EXCL_START */
errno = ret;
ret = -1;
/* LCOV_EXCL_STOP */
}
} else {
errno = EOPNOTSUPP;
ret = -1;
}
/*
* Fallback to ftruncate() if the operation is not supported.
*
* We get EOPNOTSUPP if the operation is not supported, like in ext3/ext2
* or ENOSYS with kernel before 2.6.23, because fallocate is not supported
* at all.
*
* See: man fallocate
* ENOSYS - This kernel does not implement fallocate().
* EOPNOTSUPP - The file system containing the file referred to by fd does not support this operation
*/
if (ret != 0 && (errno == EOPNOTSUPP || errno == ENOSYS)) {
/* fallback using ftruncate() */
ret = ftruncate(split->f, size);
}
#else
(void)skip_fallocate; /* avoid the warning */
/* allocate using a sparse file */
ret = ftruncate(split->f, size);
#endif
if (ret != 0)
log_tag("split:grow:%s:%" PRIu64 ": failed with error %s\n", split->path, size, strerror(errno));
else
log_tag("split:grow:%s:%" PRIu64 ": ok\n", split->path, size);
return ret;
}
static int parity_handle_shrink(struct snapraid_split_handle* split, data_off_t size)
{
int ret;
ret = ftruncate(split->f, size);
if (ret != 0)
log_tag("split:shrink:%s:%" PRIu64 ": failed with error %s\n", split->path, size, strerror(errno));
else
log_tag("split:shrink:%s:%" PRIu64 ": ok\n", split->path, size);
return ret;
}
/**
* Get the highest bit set.
*/
uint64_t hbit_u64(uint64_t v)
{
unsigned ilog;
ilog = 0;
while ((v /= 2) != 0)
++ilog;
return 1ULL << ilog;
}
static int parity_handle_fill(struct snapraid_split_handle* split, data_off_t size, uint32_t block_size, int skip_fallocate, int skip_space_holder)
{
data_off_t base;
data_off_t delta;
data_off_t block_mask;
#ifdef _WIN32
/*
* In Windows we want to avoid the annoying warning
* message of disk full.
*
* To ensure to leave some space available, we first create
* a spaceholder file >200 MB, to ensure to not fill completely
* the disk.
*/
char spaceholder_path[PATH_MAX];
pathprint(spaceholder_path, sizeof(spaceholder_path), "%s%s", split->path, ".spaceholder");
if (!skip_space_holder) {
data_off_t spaceholder_size = 256 * 1024 * 1024;
int spaceholder_f;
spaceholder_f = open(spaceholder_path, O_RDWR | O_CREAT | O_TRUNC | O_BINARY, 0600);
if (spaceholder_f == -1) {
log_fatal("Failed to create space holder file '%s'.\n", spaceholder_path);
return -1;
}
/* note that in Windows ftruncate is really allocating space */
if (ftruncate(spaceholder_f, spaceholder_size) != 0) {
log_fatal("WARNING Failed to resize the space holder file '%s' to %" PRIu64 " bytes.\n", spaceholder_path, spaceholder_size);
log_fatal("Assuming that no more space is available.\n");
close(spaceholder_f);
remove(spaceholder_path);
return 0;
}
if (fsync(spaceholder_f) != 0) {
log_fatal("Failed to sync the space holder file '%s'.\n", spaceholder_path);
close(spaceholder_f);
remove(spaceholder_path);
return -1;
}
if (close(spaceholder_f) != 0) {
log_fatal("Failed to close the space holder file '%s'.\n", spaceholder_path);
remove(spaceholder_path);
return -1;
}
}
#else
(void)skip_space_holder;
#endif
/* mask of bits used by the block size */
block_mask = ((data_off_t)block_size) - 1;
/* present size */
base = split->st.st_size;
/* truncate it to block size multiplier */
/* in case of damage the size may get wrong */
base &= ~block_mask;
/* size we have to increase */
delta = size - base;
log_tag("split:fill:%s:%" PRIu64 ":%" PRIu64 ":\n", split->path, base, size);
/* grow the size one bit at time, like a kind of binary search */
while (delta != 0) {
int ret;
data_off_t run = hbit_u64(delta);
/* mask out the bit we process */
delta &= ~run;
log_tag("split:delta:%s:%" PRIu64 ":%" PRIu64 ":\n", split->path, base, run);
ret = parity_handle_grow(split, base, base + run, skip_fallocate);
if (ret != 0) {
/* we cannot grow, fallback enabling all the smaller bits */
delta = run - 1;
/* mask out the block size */
delta &= ~block_mask;
} else {
/* increase the effective size */
base += run;
}
}
/* ensure that the resulting size if block aligned */
if ((base & block_mask) != 0) {
/* LCOV_EXCL_START */
log_fatal("Internal inconsistency in requested parity size %" PRIu64 " with block %u\n", base, block_size);
os_abort();
/* LCOV_EXCL_STOP */
}
#ifdef _WIN32
/* now delete the spaceholder file */
if (remove(spaceholder_path) != 0) {
log_fatal("WARNING Failed to remove the space holder file '%s'.\n", spaceholder_path);
log_fatal("Continuing anyway.\n");
}
#endif
/* shrink to the expected size to ensure to throw away any extra */
/* data allocated when the grow operation fails */
return parity_handle_shrink(split, base);
}
static int parity_handle_chsize(struct snapraid_split_handle* split, data_off_t size, uint32_t block_size, int skip_fallocate, int skip_space_holder)
{
int ret;
int f_ret;
int f_errno;
int f_dir;
if (split->st.st_size < size) {
f_ret = parity_handle_fill(split, size, block_size, skip_fallocate, skip_space_holder);
f_errno = errno;
f_dir = 1;
} else if (split->st.st_size > size) {
f_ret = parity_handle_shrink(split, size);
f_errno = errno;
f_dir = -1;
} else {
f_ret = 0;
f_errno = 0;
f_dir = 0;
}
/* get the stat info */
ret = fstat(split->f, &split->st);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error accessing parity file '%s'. %s.\n", split->path, strerror(errno));
return -1;
/* LCOV_EXCL_STOP */
}
/* now check the error */
if (f_ret != 0) {
/* LCOV_EXCL_START */
if (f_dir > 0) {
if (f_errno == ENOSPC) {
log_fatal("Failed to grow parity file '%s' to size %" PRIu64 " due lack of space.\n", split->path, size);
} else {
log_fatal("Error growing parity file '%s' to size %" PRIu64 ". Do you have enough space? %s.\n", split->path, size, strerror(f_errno));
}
} else {
log_fatal("Error truncating parity file '%s' to size %" PRIu64 ". %s.\n", split->path, size, strerror(f_errno));
}
return -1;
/* LCOV_EXCL_STOP */
}
2020-09-11 13:42:22 +02:00
/* if we shrink, update the valid size, but don't update when growing */
if (split->valid_size > split->st.st_size)
split->valid_size = split->st.st_size;
2019-01-07 14:06:15 +01:00
return 0;
}
static int parity_split_is_fixed(struct snapraid_parity_handle* handle, unsigned s)
{
/* next one */
++s;
/* the latest one is always growing */
if (s >= handle->split_mac)
return 0;
/* if the next it's 0, this one is growing */
if (handle->split_map[s].size == 0)
return 0;
return 1;
}
int parity_chsize(struct snapraid_parity_handle* handle, struct snapraid_parity* parity, int* is_modified, data_off_t size, uint32_t block_size, int skip_fallocate, int skip_space_holder)
{
int ret;
unsigned s;
data_off_t block_mask;
/* mask of bits used by the block size */
block_mask = ((data_off_t)block_size) - 1;
if (size < 0) {
/* LCOV_EXCL_START */
return -1;
/* LCOV_EXCL_STOP */
}
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int is_fixed = parity_split_is_fixed(handle, s);
data_off_t run;
if (is_fixed) {
/* if the required size is smaller, we have to reduce also the file */
/* ignoring the previous size */
if (size <= split->size) {
/* mark it as not fixed anymore for the later check */
is_fixed = 0;
run = size; /* allocate only the needed size */
} else {
/* if the size cannot be changed, use the fixed one */
run = split->size;
if ((run & block_mask) != 0) {
/* LCOV_EXCL_START */
log_fatal("Internal inconsistency in split '%s' size with extra '%" PRIu64 "' bytes.\n", split->path, run & block_mask);
return -1;
/* LCOV_EXCL_STOP */
}
}
} else {
/* otherwise tries to allocate all the needed remaining size */
run = size;
}
ret = parity_handle_chsize(split, run, block_size, skip_fallocate, skip_space_holder);
if (ret != 0) {
/* LCOV_EXCL_START */
return -1;
/* LCOV_EXCL_STOP */
}
if (split->st.st_size > run) {
/* LCOV_EXCL_START */
log_fatal("Unexpected over resizing parity file '%s' to size %" PRIu64 " resulting in size %" PRIu64 ".\n", split->path, run, (uint64_t)split->st.st_size);
return -1;
/* LCOV_EXCL_STOP */
} else if (is_fixed && split->st.st_size < run) {
/* LCOV_EXCL_START */
log_fatal("Failed restoring parity file '%s' to size %" PRIu64 " resulting in size %" PRIu64 ".\n", split->path, run, (uint64_t)split->st.st_size);
return -1;
/* LCOV_EXCL_STOP */
} else {
/* here it's possible to get less than the requested size */
run = split->st.st_size;
if ((run & block_mask) != 0) {
/* LCOV_EXCL_START */
log_fatal("Internal inconsistency in final parity size %" PRIu64 " with block size %u\n", run, block_size);
os_abort();
/* LCOV_EXCL_STOP */
}
/* store what we have allocated */
split->size = run;
/* decrease the remaining size */
size -= run;
}
}
/* if we cannot allocate all the space */
if (size != 0) {
/* LCOV_EXCL_START */
log_fatal("Failed to allocate all the required parity space. You miss %" PRIu64 " bytes.\n", size);
return -1;
/* LCOV_EXCL_STOP */
}
/* now copy the new size in the parity data */
if (is_modified)
*is_modified = 0;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
if (parity->split_map[s].size != split->size) {
parity->split_map[s].size = split->size;
if (is_modified)
*is_modified = 1;
}
}
return 0;
}
int parity_open(struct snapraid_parity_handle* handle, const struct snapraid_parity* parity, unsigned level, int mode, uint32_t block_size, data_off_t limit_size)
{
unsigned s;
data_off_t block_mask;
handle->level = level;
handle->split_mac = 0;
/* mask of bits used by the block size */
block_mask = ((data_off_t)block_size) - 1;
for (s = 0; s < parity->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int ret;
int flags;
advise_init(&split->advise, mode);
pathcpy(split->path, sizeof(split->path), parity->split_map[s].path);
split->size = parity->split_map[s].size;
split->limit_size = PARITY_LIMIT(limit_size, s, level);
/* open for read */
/* O_NOATIME: do not change access time */
flags = O_RDONLY | O_BINARY | advise_flags(&split->advise);
split->f = open_noatime(split->path, flags);
if (split->f == -1) {
/* LCOV_EXCL_START */
log_fatal("Error opening parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
/* we have a valid file handle */
++handle->split_mac;
/* get the stat info */
ret = fstat(split->f, &split->st);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error accessing parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
2020-09-11 13:42:22 +02:00
/* the initial valid size is the size on disk */
split->valid_size = split->st.st_size;
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/**
* If the parity size is not yet set, set it now.
* This happens when expanding the number of parities,
* or when upgrading from a content file that has not split->size data.
*/
if (split->size == PARITY_SIZE_INVALID) {
split->size = split->st.st_size;
/* ensure that the resulting size if block aligned */
if ((split->size & block_mask) != 0) {
/* LCOV_EXCL_START */
log_fatal("Error in preallocated size of parity file '%s' with size %" PRIu64 " and block %u .\n", split->path, split->size, block_size);
goto bail;
/* LCOV_EXCL_STOP */
}
}
ret = advise_open(&split->advise, split->f);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error advising parity file '%s'. %s.\n", split->path, strerror(errno));
goto bail;
/* LCOV_EXCL_STOP */
}
}
return 0;
bail:
/* LCOV_EXCL_START */
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
close(split->f);
split->f = -1;
}
return -1;
/* LCOV_EXCL_STOP */
}
int parity_sync(struct snapraid_parity_handle* handle)
{
#if HAVE_FSYNC
unsigned s;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int ret;
/* Ensure that data changes are written to disk. */
/* This is required to ensure that parity is more updated than content */
/* in case of a system crash. */
ret = fsync(split->f);
if (ret != 0) {
/* LCOV_EXCL_START */
2020-09-11 13:42:22 +02:00
log_fatal("Error syncing parity file '%s'. %s.\n", split->path, strerror(errno));
2019-01-07 14:06:15 +01:00
return -1;
/* LCOV_EXCL_STOP */
}
}
#endif
return 0;
}
2020-09-11 13:42:22 +02:00
int parity_truncate(struct snapraid_parity_handle* handle)
{
unsigned s;
int f_ret = 0;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int ret;
/* truncate any data that we know it's not valid */
ret = ftruncate(split->f, split->valid_size);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error truncating the parity file '%s' to size %" PRIu64 ". %s.\n", split->path, split->valid_size, strerror(errno));
f_ret = -1;
/* LCOV_EXCL_STOP */
/* continue to truncate the others */
}
}
return f_ret;
}
2019-01-07 14:06:15 +01:00
int parity_close(struct snapraid_parity_handle* handle)
{
unsigned s;
int f_ret = 0;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
int ret;
ret = close(split->f);
if (ret != 0) {
/* LCOV_EXCL_START */
/* This is a serious error, as it may be the result of a failed write */
/* identified at later time. */
/* In a normal file-system (not NFS) it should never happen */
log_fatal("Error closing parity file '%s'. %s.\n", split->path, strerror(errno));
f_ret = -1;
/* LCOV_EXCL_STOP */
/* continue to close the others */
}
/* reset the descriptor */
split->f = -1;
}
return f_ret;
}
struct snapraid_split_handle* parity_split_find(struct snapraid_parity_handle* handle, data_off_t* offset)
{
unsigned s;
if (*offset < 0)
return 0;
for (s = 0; s < handle->split_mac; ++s) {
struct snapraid_split_handle* split = &handle->split_map[s];
if (*offset < split->size)
return split;
*offset -= split->size;
}
return 0;
}
int parity_write(struct snapraid_parity_handle* handle, block_off_t pos, unsigned char* block_buffer, unsigned block_size)
{
ssize_t write_ret;
data_off_t offset;
struct snapraid_split_handle* split;
int ret;
offset = pos * (data_off_t)block_size;
split = parity_split_find(handle, &offset);
if (!split) {
/* LCOV_EXCL_START */
log_fatal("Writing parity data outside range at extra offset %" PRIu64 ".\n", offset);
return -1;
/* LCOV_EXCL_STOP */
}
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/* update the valid range */
if (split->valid_size < offset + block_size)
split->valid_size = offset + block_size;
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write_ret = pwrite(split->f, block_buffer, block_size, offset);
if (write_ret != (ssize_t)block_size) { /* conversion is safe because block_size is always small */
/* LCOV_EXCL_START */
if (errno == ENOSPC) {
log_fatal("Failed to grow parity file '%s' using write due lack of space.\n", split->path);
} else {
log_fatal("Error writing file '%s'. %s.\n", split->path, strerror(errno));
}
return -1;
/* LCOV_EXCL_STOP */
}
ret = advise_write(&split->advise, split->f, offset, block_size);
if (ret != 0) {
/* LCOV_EXCL_START */
log_fatal("Error advising parity file '%s'. %s.\n", split->path, strerror(errno));
return -1;
/* LCOV_EXCL_STOP */
}
return 0;
}
int parity_read(struct snapraid_parity_handle* handle, block_off_t pos, unsigned char* block_buffer, unsigned block_size, fptr* out)
{
ssize_t read_ret;
data_off_t offset;
unsigned count;
struct snapraid_split_handle* split;
int ret;
offset = pos * (data_off_t)block_size;
split = parity_split_find(handle, &offset);
if (!split) {
/* LCOV_EXCL_START */
out("Reading parity data outside range at extra offset %" PRIu64 ".\n", offset);
return -1;
/* LCOV_EXCL_STOP */
}
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/* if read is completely out of the valid range */
if (offset >= split->valid_size) {
/* LCOV_EXCL_START */
out("Missing data reading file '%s' at offset %" PRIu64 " for size %u.\n", split->path, offset, block_size);
return -1;
/* LCOV_EXCL_STOP */
}
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count = 0;
do {
read_ret = pread(split->f, block_buffer + count, block_size - count, offset + count);
if (read_ret < 0) {
/* LCOV_EXCL_START */
out("Error reading file '%s' at offset %" PRIu64 " for size %u. %s.\n", split->path, offset + count, block_size - count, strerror(errno));
return -1;
/* LCOV_EXCL_STOP */
}
if (read_ret == 0) {
/* LCOV_EXCL_START */
out("Unexpected end of file '%s' at offset %" PRIu64 ". %s.\n", split->path, offset, strerror(errno));
return -1;
/* LCOV_EXCL_STOP */
}
count += read_ret;
} while (count < block_size);
ret = advise_read(&split->advise, split->f, offset, block_size);
if (ret != 0) {
/* LCOV_EXCL_START */
out("Error advising parity file '%s'. %s.\n", split->path, strerror(errno));
return -1;
/* LCOV_EXCL_STOP */
}
return block_size;
}