diff options
Diffstat (limited to 'src/server/image.c')
| -rw-r--r-- | src/server/image.c | 685 |
1 files changed, 490 insertions, 195 deletions
diff --git a/src/server/image.c b/src/server/image.c index 16dae45..51fd5b6 100644 --- a/src/server/image.c +++ b/src/server/image.c @@ -5,9 +5,9 @@ #include "locks.h" #include "integrity.h" #include "altservers.h" -#include "../shared/protocol.h" -#include "../shared/timing.h" -#include "../shared/crc32.h" +#include <dnbd3/shared/protocol.h> +#include <dnbd3/shared/timing.h> +#include <dnbd3/shared/crc32.h> #include "reference.h" #include <assert.h> @@ -46,16 +46,21 @@ static dnbd3_image_t* image_remove(dnbd3_image_t *image); static dnbd3_image_t* image_free(dnbd3_image_t *image); static bool image_load_all_internal(char *base, char *path); static bool image_addToList(dnbd3_image_t *image); -static bool image_load(char *base, char *path, int withUplink); +static bool image_load(char *base, char *path, bool withUplink); static bool image_clone(int sock, char *name, uint16_t revision, uint64_t imageSize); static bool image_calcBlockCrc32(const int fd, const size_t block, const uint64_t realFilesize, uint32_t *crc); static bool image_ensureDiskSpace(uint64_t size, bool force); static dnbd3_cache_map_t* image_loadCacheMap(const char * const imagePath, const int64_t fileSize); static uint32_t* image_loadCrcList(const char * const imagePath, const int64_t fileSize, uint32_t *masterCrc); -static void image_checkRandomBlocks(dnbd3_image_t *image, const int count); +static bool image_checkRandomBlocks(dnbd3_image_t *image, const int count, int fromFd); static void* closeUnusedFds(void*); +static bool isImageFromUpstream(dnbd3_image_t *image); +static void* saveLoadAllCacheMaps(void*); +static void saveCacheMap(dnbd3_image_t *image); static void allocCacheMap(dnbd3_image_t *image, bool complete); +static void saveMetaData(dnbd3_image_t *image, ticks *now, time_t walltime); +static void loadImageMeta(dnbd3_image_t *image); static void cmfree(ref *ref) { @@ -73,6 +78,7 @@ void image_serverStartup() mutex_init( &remoteCloneLock, LOCK_REMOTE_CLONE ); mutex_init( &reloadLock, LOCK_RELOAD ); server_addJob( &closeUnusedFds, NULL, 10, 900 ); + server_addJob( &saveLoadAllCacheMaps, NULL, 9, 20 ); } /** @@ -118,39 +124,35 @@ void image_updateCachemap(dnbd3_image_t *image, uint64_t start, uint64_t end, co const uint64_t firstByteInMap = start >> 15; const uint64_t lastByteInMap = (end - 1) >> 15; uint64_t pos; - // First byte - uint8_t fb = 0, lb = 0; - for ( pos = start; firstByteInMap == (pos >> 15) && pos < end; pos += DNBD3_BLOCK_SIZE ) { - const int map_x = (pos >> 12) & 7; // mod 8 - const uint8_t bit_mask = (uint8_t)( 1 << map_x ); - fb |= bit_mask; - } - // Last byte - if ( lastByteInMap != firstByteInMap ) { - for ( pos = lastByteInMap << 15; pos < end; pos += DNBD3_BLOCK_SIZE ) { - assert( lastByteInMap == (pos >> 15) ); - const int map_x = (pos >> 12) & 7; // mod 8 - const uint8_t bit_mask = (uint8_t)( 1 << map_x ); - lb |= bit_mask; - } - } - atomic_thread_fence( memory_order_acquire ); - if ( set ) { - uint8_t fo = atomic_fetch_or_explicit( &cache->map[firstByteInMap], fb, memory_order_relaxed ); - uint8_t lo = atomic_fetch_or_explicit( &cache->map[lastByteInMap], lb, memory_order_relaxed ); - setNewBlocks = ( fo != cache->map[firstByteInMap] || lo != cache->map[lastByteInMap] ); + // First and last byte masks + const uint8_t fb = (uint8_t)(0xff << ((start >> 12) & 7)); + const uint8_t lb = (uint8_t)(~(0xff << ((((end - 1) >> 12) & 7) + 1))); + if ( firstByteInMap == lastByteInMap ) { + if ( set ) { + uint8_t o = atomic_fetch_or( &cache->map[firstByteInMap], (uint8_t)(fb & lb) ); + setNewBlocks = o != ( o | (fb & lb) ); + } else { + atomic_fetch_and( &cache->map[firstByteInMap], (uint8_t)~(fb & lb) ); + } } else { - atomic_fetch_and_explicit( &cache->map[firstByteInMap], (uint8_t)~fb, memory_order_relaxed ); - atomic_fetch_and_explicit( &cache->map[lastByteInMap], (uint8_t)~lb, memory_order_relaxed ); - } - const uint8_t nval = set ? 0xff : 0; - // Everything in between - for ( pos = firstByteInMap + 1; pos < lastByteInMap; ++pos ) { - if ( atomic_exchange_explicit( &cache->map[pos], nval, memory_order_relaxed ) != nval && set ) { - setNewBlocks = true; + atomic_thread_fence( memory_order_acquire ); + if ( set ) { + uint8_t fo = atomic_fetch_or_explicit( &cache->map[firstByteInMap], fb, memory_order_relaxed ); + uint8_t lo = atomic_fetch_or_explicit( &cache->map[lastByteInMap], lb, memory_order_relaxed ); + setNewBlocks = ( fo != ( fo | fb ) || lo != ( lo | lb ) ); + } else { + atomic_fetch_and_explicit( &cache->map[firstByteInMap], (uint8_t)~fb, memory_order_relaxed ); + atomic_fetch_and_explicit( &cache->map[lastByteInMap], (uint8_t)~lb, memory_order_relaxed ); + } + // Everything in between + const uint8_t nval = set ? 0xff : 0; + for ( pos = firstByteInMap + 1; pos < lastByteInMap; ++pos ) { + if ( atomic_exchange_explicit( &cache->map[pos], nval, memory_order_relaxed ) != nval && set ) { + setNewBlocks = true; + } } + atomic_thread_fence( memory_order_release ); } - atomic_thread_fence( memory_order_release ); if ( setNewBlocks && image->crc32 != NULL ) { // If setNewBlocks is set, at least one of the blocks was not cached before, so queue all hash blocks // for checking, even though this might lead to checking some hash block again, if it was @@ -164,6 +166,8 @@ void image_updateCachemap(dnbd3_image_t *image, uint64_t start, uint64_t end, co integrity_check( image, block, false ); } } + } else if ( !set ) { + cache->dirty = true; } ref_put( &cache->reference ); } @@ -239,35 +243,74 @@ bool image_isComplete(dnbd3_image_t *image) */ bool image_ensureOpen(dnbd3_image_t *image) { - if ( image->readFd != -1 ) return image; - int newFd = open( image->path, O_RDONLY ); + bool sizeChanged = false; + if ( image->readFd != -1 && !image->problem.changed ) + return true; + int newFd = image->readFd == -1 ? open( image->path, O_RDONLY ) : dup( image->readFd ); if ( newFd == -1 ) { - logadd( LOG_WARNING, "Cannot open %s for reading", image->path ); + if ( !image->problem.read ) { + logadd( LOG_WARNING, "[access] Cannot open '%s' for reading (errno=%d)", image->path, errno ); + image->problem.read = true; + } } else { - // Check size + // Check size + read access + char buffer[100]; const off_t flen = lseek( newFd, 0, SEEK_END ); if ( flen == -1 ) { - logadd( LOG_WARNING, "Could not seek to end of %s (errno %d)", image->path, errno ); + if ( !image->problem.read ) { + logadd( LOG_WARNING, "Could not seek to end of %s (errno=%d)", image->path, errno ); + image->problem.read = true; + } close( newFd ); newFd = -1; } else if ( (uint64_t)flen != image->realFilesize ) { - logadd( LOG_WARNING, "Size of active image with closed fd changed from %" PRIu64 " to %" PRIu64, image->realFilesize, (uint64_t)flen ); + if ( !image->problem.changed ) { + logadd( LOG_WARNING, "Size of active image with closed fd changed from %" PRIu64 " to %" PRIu64, + image->realFilesize, (uint64_t)flen ); + } + sizeChanged = true; + } else if ( pread( newFd, buffer, sizeof(buffer), 0 ) == -1 ) { + if ( !image->problem.read ) { + logadd( LOG_WARNING, "Reading first %d bytes from %s failed (errno=%d)", + (int)sizeof(buffer), image->path, errno ); + image->problem.read = true; + } close( newFd ); newFd = -1; } } if ( newFd == -1 ) { - mutex_lock( &image->lock ); - image->working = false; - mutex_unlock( &image->lock ); + if ( sizeChanged ) { + image->problem.changed = true; + } return false; } + + // Re-opened. Check if the "size/content changed" flag was set before and if so, check crc32, + // but only if the size we just got above is correct. + if ( image->problem.changed && !sizeChanged ) { + if ( image->crc32 == NULL ) { + // Cannot verify further, hope for the best + image->problem.changed = false; + logadd( LOG_DEBUG1, "Size of image %s:%d changed back to expected value", PIMG(image) ); + } else if ( image_checkRandomBlocks( image, 1, newFd ) ) { + // This should have checked the first block (if complete) -> All is well again + image->problem.changed = false; + logadd( LOG_DEBUG1, "Size and CRC of image %s:%d changed back to expected value", PIMG(image) ); + } + } else { + image->problem.changed = sizeChanged; + } + mutex_lock( &image->lock ); if ( image->readFd == -1 ) { image->readFd = newFd; + image->problem.read = false; mutex_unlock( &image->lock ); } else { - // There was a race while opening the file (happens cause not locked cause blocking), we lost the race so close new fd and proceed + // There was a race while opening the file (happens cause not locked cause blocking), + // we lost the race so close new fd and proceed. + // *OR* we dup()'ed above for cheating when the image changed before. mutex_unlock( &image->lock ); close( newFd ); } @@ -296,10 +339,9 @@ dnbd3_image_t* image_byId(int imgId) * point... * Locks on: imageListLock, _images[].lock */ -dnbd3_image_t* image_get(char *name, uint16_t revision, bool checkIfWorking) +dnbd3_image_t* image_get(const char *name, uint16_t revision, bool ensureFdOpen) { int i; - const char *removingText = _removeMissingImages ? ", removing from list" : ""; dnbd3_image_t *candidate = NULL; // Simple sanity check const size_t slen = strlen( name ); @@ -326,84 +368,36 @@ dnbd3_image_t* image_get(char *name, uint16_t revision, bool checkIfWorking) candidate->users++; mutex_unlock( &imageListLock ); - // Found, see if it works - // TODO: Also make sure a non-working image still has old fd open but created a new one and removed itself from the list - // TODO: But remember size-changed images forever - if ( candidate->working || checkIfWorking ) { - // Is marked working, but might not have an fd open - if ( !image_ensureOpen( candidate ) ) { - mutex_lock( &candidate->lock ); - timing_get( &candidate->lastWorkCheck ); - mutex_unlock( &candidate->lock ); - if ( _removeMissingImages ) { - candidate = image_remove( candidate ); // No release here, the image is still returned and should be released by caller - } - return candidate; - } - } - - if ( !checkIfWorking ) return candidate; // Not interested in re-cechking working state - - // ...not working... - - // Don't re-check too often - mutex_lock( &candidate->lock ); - bool check; - declare_now; - check = timing_diff( &candidate->lastWorkCheck, &now ) > NONWORKING_RECHECK_INTERVAL_SECONDS; - if ( check ) { - candidate->lastWorkCheck = now; - } - mutex_unlock( &candidate->lock ); - if ( !check ) { + if ( !ensureFdOpen ) // Don't want to re-check return candidate; - } - // reaching this point means: - // 1) We should check if the image is working, it might or might not be in working state right now - // 2) The image is open for reading (or at least was at some point, the fd might be stale if images lie on an NFS share etc.) - // 3) We made sure not to re-check this image too often - - // Common for ro and rw images: Size check, read check - const off_t len = lseek( candidate->readFd, 0, SEEK_END ); - bool reload = false; - if ( len == -1 ) { - logadd( LOG_WARNING, "lseek() on %s failed (errno=%d)%s.", candidate->path, errno, removingText ); - reload = true; - } else if ( (uint64_t)len != candidate->realFilesize ) { - logadd( LOG_WARNING, "Size of %s changed at runtime, keeping disabled! Expected: %" PRIu64 ", found: %" PRIu64 - ". Try sending SIGHUP to server if you know what you're doing.", - candidate->path, candidate->realFilesize, (uint64_t)len ); - } else { - // Seek worked, file size is same, now see if we can read from file - char buffer[100]; - if ( pread( candidate->readFd, buffer, sizeof(buffer), 0 ) == -1 ) { - logadd( LOG_WARNING, "Reading first %d bytes from %s failed (errno=%d)%s.", - (int)sizeof(buffer), candidate->path, errno, removingText ); - reload = true; - } else if ( !candidate->working ) { - // Seems everything is fine again \o/ - candidate->working = true; - logadd( LOG_INFO, "Changed state of %s:%d to 'working'", candidate->name, candidate->rid ); - } - } + if ( image_ensureOpen( candidate ) && !candidate->problem.read ) + return candidate; // We have a read fd and no read or changed problems - if ( reload ) { + // -- image could not be opened again, or is open but has problem -- + + if ( _removeMissingImages && !file_isReadable( candidate->path ) ) { + candidate = image_remove( candidate ); + // No image_release here, the image is still returned and should be released by caller + } else if ( candidate->readFd != -1 ) { + // We cannot just close the fd as it might be in use. Make a copy and remove old entry. + candidate = image_remove( candidate ); // Could not access the image with exising fd - mark for reload which will re-open the file. // make a copy of the image struct but keep the old one around. If/When it's not being used // anymore, it will be freed automatically. - logadd( LOG_DEBUG1, "Reloading image file %s", candidate->path ); + logadd( LOG_DEBUG1, "Reloading image file %s because of read problem/changed", candidate->path ); dnbd3_image_t *img = calloc( sizeof(dnbd3_image_t), 1 ); img->path = strdup( candidate->path ); img->name = strdup( candidate->name ); img->virtualFilesize = candidate->virtualFilesize; img->realFilesize = candidate->realFilesize; - img->atime = now; + timing_get( &img->atime ); img->masterCrc32 = candidate->masterCrc32; img->readFd = -1; img->rid = candidate->rid; img->users = 1; - img->working = false; + img->problem.read = true; + img->problem.changed = candidate->problem.changed; img->ref_cacheMap = NULL; mutex_init( &img->lock, LOCK_IMAGE ); if ( candidate->crc32 != NULL ) { @@ -419,18 +413,17 @@ dnbd3_image_t* image_get(char *name, uint16_t revision, bool checkIfWorking) if ( image_addToList( img ) ) { image_release( candidate ); candidate = img; + // Check if image is incomplete, initialize uplink + if ( candidate->ref_cacheMap != NULL ) { + uplink_init( candidate, -1, NULL, -1 ); + } + // Try again with new instance + image_ensureOpen( candidate ); } else { img->users = 0; image_free( img ); } - // Check if image is incomplete, initialize uplink - if ( candidate->ref_cacheMap != NULL ) { - uplink_init( candidate, -1, NULL, -1 ); - } - // readFd == -1 and working == FALSE at this point, - // this function needs some splitting up for handling as we need to run most - // of the above code again. for now we know that the next call for this - // name:rid will get ne newly inserted "img" and try to re-open the file. + // readFd == -1 and problem.read == true } return candidate; // We did all we can, hopefully it's working @@ -449,6 +442,7 @@ dnbd3_image_t* image_lock(dnbd3_image_t *image) mutex_lock( &imageListLock ); for (i = 0; i < _num_images; ++i) { if ( _images[i] == image ) { + assert( _images[i]->id == image->id ); image->users++; mutex_unlock( &imageListLock ); return image; @@ -479,6 +473,7 @@ dnbd3_image_t* image_release(dnbd3_image_t *image) // responsible for freeing it for (int i = 0; i < _num_images; ++i) { if ( _images[i] == image ) { // Found, do nothing + assert( _images[i]->id == image->id ); mutex_unlock( &imageListLock ); return NULL; } @@ -518,6 +513,7 @@ static dnbd3_image_t* image_remove(dnbd3_image_t *image) mutex_lock( &imageListLock ); for ( int i = _num_images - 1; i >= 0; --i ) { if ( _images[i] == image ) { + assert( _images[i]->id == image->id ); _images[i] = NULL; mustFree = ( image->users == 0 ); } @@ -630,12 +626,18 @@ static dnbd3_image_t* image_free(dnbd3_image_t *image) { assert( image != NULL ); assert( image->users == 0 ); - logadd( ( _shutdown ? LOG_DEBUG1 : LOG_INFO ), "Freeing image %s:%d", image->name, (int)image->rid ); + logadd( ( _shutdown ? LOG_DEBUG1 : LOG_INFO ), "Freeing image %s:%d", PIMG(image) ); // uplink_shutdown might return false to tell us // that the shutdown is in progress. Bail out since // this will get called again when the uplink is done. if ( !uplink_shutdown( image ) ) return NULL; + if ( isImageFromUpstream( image ) ) { + saveMetaData( image, NULL, 0 ); + if ( image->ref_cacheMap != NULL ) { + saveCacheMap( image ); + } + } mutex_lock( &image->lock ); ref_setref( &image->ref_cacheMap, NULL ); free( image->crc32 ); @@ -700,7 +702,8 @@ static bool image_load_all_internal(char *base, char *path) while ( !_shutdown && (entryPtr = readdir( dir )) != NULL ) { entry = *entryPtr; - if ( strcmp( entry.d_name, "." ) == 0 || strcmp( entry.d_name, ".." ) == 0 ) continue; + if ( entry.d_name[0] == '.' ) + continue; // No hidden files, no . or .. if ( strlen( entry.d_name ) > SUBDIR_LEN ) { logadd( LOG_WARNING, "Skipping entry %s: Too long (max %d bytes)", entry.d_name, (int)SUBDIR_LEN ); continue; @@ -717,7 +720,7 @@ static bool image_load_all_internal(char *base, char *path) if ( S_ISDIR( st.st_mode ) ) { image_load_all_internal( base, subpath ); // Recurse } else if ( !isForbiddenExtension( subpath ) ) { - image_load( base, subpath, true ); // Load image if possible + image_load( base, subpath, false ); // Load image if possible } } closedir( dir ); @@ -756,10 +759,9 @@ static bool image_addToList(dnbd3_image_t *image) * Note that this is NOT THREAD SAFE so make sure its always * called on one thread only. */ -static bool image_load(char *base, char *path, int withUplink) +static bool image_load(char *base, char *path, bool withUplink) { int revision = -1; - struct stat st; dnbd3_cache_map_t *cache = NULL; uint32_t *crc32list = NULL; dnbd3_image_t *existing = NULL; @@ -824,7 +826,9 @@ static bool image_load(char *base, char *path, int withUplink) fdImage = open( path, O_RDONLY ); } if ( fdImage == -1 ) { - logadd( LOG_ERROR, "Could not open '%s' for reading...", path ); + if ( errno != ENOENT ) { + logadd( LOG_ERROR, "[load] Cannot open '%s' for reading (errno=%d)", path, errno ); + } goto load_error; } // Determine file size @@ -855,16 +859,16 @@ static bool image_load(char *base, char *path, int withUplink) // Compare data just loaded to identical image we apparently already loaded if ( existing != NULL ) { if ( existing->realFilesize != realFilesize ) { - logadd( LOG_WARNING, "Size of image '%s:%d' has changed.", existing->name, (int)existing->rid ); + logadd( LOG_WARNING, "Size of image '%s:%d' has changed.", PIMG(existing) ); // Image will be replaced below } else if ( existing->crc32 != NULL && crc32list != NULL && memcmp( existing->crc32, crc32list, sizeof(uint32_t) * hashBlockCount ) != 0 ) { - logadd( LOG_WARNING, "CRC32 list of image '%s:%d' has changed.", existing->name, (int)existing->rid ); + logadd( LOG_WARNING, "CRC32 list of image '%s:%d' has changed.", PIMG(existing) ); logadd( LOG_WARNING, "The image will be reloaded, but you should NOT replace existing images while the server is running." ); logadd( LOG_WARNING, "Actually even if it's not running this should never be done. Use a new RID instead!" ); // Image will be replaced below } else if ( existing->crc32 == NULL && crc32list != NULL ) { - logadd( LOG_INFO, "Found CRC-32 list for already loaded image '%s:%d', adding...", existing->name, (int)existing->rid ); + logadd( LOG_INFO, "Found CRC-32 list for already loaded image '%s:%d', adding...", PIMG(existing) ); existing->crc32 = crc32list; existing->masterCrc32 = masterCrc; crc32list = NULL; @@ -872,7 +876,7 @@ static bool image_load(char *base, char *path, int withUplink) goto load_error; // Keep existing } else if ( existing->ref_cacheMap != NULL && cache == NULL ) { // Just ignore that fact, if replication is really complete the cache map will be removed anyways - logadd( LOG_INFO, "Image '%s:%d' has no cache map on disk!", existing->name, (int)existing->rid ); + logadd( LOG_INFO, "Image '%s:%d' has no cache map on disk!", PIMG(existing) ); function_return = true; goto load_error; // Keep existing } else { @@ -900,19 +904,10 @@ static bool image_load(char *base, char *path, int withUplink) image->rid = (uint16_t)revision; image->users = 0; image->readFd = -1; - image->working = ( cache == NULL ); timing_get( &image->nextCompletenessEstimate ); image->completenessEstimate = -1; mutex_init( &image->lock, LOCK_IMAGE ); - int32_t offset; - if ( stat( path, &st ) == 0 ) { - // Negatively offset atime by file modification time - offset = (int32_t)( st.st_mtime - time( NULL ) ); - if ( offset > 0 ) offset = 0; - } else { - offset = 0; - } - timing_gets( &image->atime, offset ); + loadImageMeta( image ); // Prevent freeing in cleanup cache = NULL; @@ -925,7 +920,7 @@ static bool image_load(char *base, char *path, int withUplink) // Image is definitely incomplete, initialize uplink worker if ( image->ref_cacheMap != NULL ) { - image->working = false; + image->problem.uplink = true; if ( withUplink ) { uplink_init( image, -1, NULL, -1 ); } @@ -937,14 +932,14 @@ static bool image_load(char *base, char *path, int withUplink) // Keep fd for reading fdImage = -1; // Check CRC32 - image_checkRandomBlocks( image, 4 ); + image_checkRandomBlocks( image, 4, -1 ); } else { logadd( LOG_ERROR, "Image list full: Could not add image %s", path ); image->readFd = -1; // Keep fdImage instead, will be closed below image = image_free( image ); goto load_error; } - logadd( LOG_DEBUG1, "Loaded image '%s:%d'\n", image->name, (int)image->rid ); + logadd( LOG_DEBUG1, "Loaded image '%s:%d'\n", PIMG(image) ); function_return = true; // Clean exit: @@ -1027,10 +1022,19 @@ static uint32_t* image_loadCrcList(const char * const imagePath, const int64_t f return retval; } -static void image_checkRandomBlocks(dnbd3_image_t *image, const int count) +/** + * Check up to count random blocks from given image. If fromFd is -1, the check will + * be run asynchronously using the integrity checker. Otherwise, the check will + * happen in the function and return the result of the check. + * @param image image to check + * @param count number of blocks to check (max) + * @param fromFd, check synchronously and use this fd for reading, -1 = async + * @return true = OK, false = error. Meaningless if fromFd == -1 + */ +static bool image_checkRandomBlocks(dnbd3_image_t *image, const int count, int fromFd) { if ( image->crc32 == NULL ) - return; + return true; // This checks the first block and (up to) count - 1 random blocks for corruption // via the known crc32 list. This is very sloppy and is merely supposed to detect // accidental corruption due to broken dnbd3-proxy functionality or file system @@ -1038,7 +1042,7 @@ static void image_checkRandomBlocks(dnbd3_image_t *image, const int count) assert( count > 0 ); dnbd3_cache_map_t *cache = ref_get_cachemap( image ); const int hashBlocks = IMGSIZE_TO_HASHBLOCKS( image->virtualFilesize ); - int blocks[count]; + int blocks[count+1]; // +1 for "-1" in sync case int index = 0, j; int block; if ( image_isHashBlockComplete( cache, 0, image->virtualFilesize ) ) { @@ -1062,9 +1066,16 @@ while_end: ; if ( cache != NULL ) { ref_put( &cache->reference ); } - for ( int i = 0; i < index; ++i ) { - integrity_check( image, blocks[i], true ); + if ( fromFd == -1 ) { + // Async + for ( int i = 0; i < index; ++i ) { + integrity_check( image, blocks[i], true ); + } + return true; } + // Sync + blocks[index] = -1; + return image_checkBlocksCrc32( fromFd, image->crc32, blocks, image->realFilesize ); } /** @@ -1079,7 +1090,7 @@ bool image_create(char *image, int revision, uint64_t size) logadd( LOG_ERROR, "revision id invalid: %d", revision ); return false; } - char path[PATHLEN], cache[PATHLEN]; + char path[PATHLEN], cache[PATHLEN+4]; char *lastSlash = strrchr( image, '/' ); if ( lastSlash == NULL ) { snprintf( path, PATHLEN, "%s/%s.r%d", _basePath, image, revision ); @@ -1090,7 +1101,7 @@ bool image_create(char *image, int revision, uint64_t size) *lastSlash = '/'; snprintf( path, PATHLEN, "%s/%s.r%d", _basePath, image, revision ); } - snprintf( cache, PATHLEN, "%s.map", path ); + snprintf( cache, PATHLEN+4, "%s.map", path ); size = (size + DNBD3_BLOCK_SIZE - 1) & ~(uint64_t)(DNBD3_BLOCK_SIZE - 1); const int mapsize = IMGSIZE_TO_MAPBYTES(size); // Write files @@ -1111,14 +1122,19 @@ bool image_create(char *image, int revision, uint64_t size) logadd( LOG_DEBUG1, "Could not allocate %d bytes for %s (errno=%d)", mapsize, cache, err ); } // Now write image + bool fallback = false; if ( !_sparseFiles && !file_alloc( fdImage, 0, size ) ) { logadd( LOG_ERROR, "Could not allocate %" PRIu64 " bytes for %s (errno=%d)", size, path, errno ); logadd( LOG_ERROR, "It is highly recommended to use a file system that supports preallocating disk" " space without actually writing all zeroes to the block device." ); logadd( LOG_ERROR, "If you cannot fix this, try setting sparseFiles=true, but don't expect" " divine performance during replication." ); - goto failure_cleanup; - } else if ( _sparseFiles && !file_setSize( fdImage, size ) ) { + if ( !_ignoreAllocErrors ) { + goto failure_cleanup; + } + fallback = true; + } + if ( ( _sparseFiles || fallback ) && !file_setSize( fdImage, size ) ) { logadd( LOG_ERROR, "Could not create sparse file of %" PRIu64 " bytes for %s (errno=%d)", size, path, errno ); logadd( LOG_ERROR, "Make sure you have enough disk space, check directory permissions, fs errors etc." ); goto failure_cleanup; @@ -1162,14 +1178,18 @@ dnbd3_image_t* image_getOrLoad(char * const name, const uint16_t revision) // Sanity check if ( len == 0 || name[len - 1] == '/' || name[0] == '/' || name[0] == '.' || strstr( name, "/." ) != NULL ) return NULL; - // If in proxy mode, check with upstream server first + // Re-check latest local revision + image = loadImageServer( name, revision ); + // If in proxy mode, check with upstream servers if ( _isProxy ) { + // Forget the locally loaded one + image_release( image ); + // Check with upstream - if unsuccessful, will return the same + // as loadImageServer did image = loadImageProxy( name, revision, len ); - if ( image != NULL ) - return image; } // Lookup on local storage - return loadImageServer( name, revision ); + return image; } /** @@ -1227,19 +1247,20 @@ static dnbd3_image_t *loadImageProxy(char * const name, const uint16_t revision, int uplinkSock = -1; dnbd3_host_t uplinkServer; const int count = altservers_getHostListForReplication( name, servers, REP_NUM_SRV ); - uint16_t remoteProtocolVersion; uint16_t remoteRid = revision; - uint64_t remoteImageSize; + uint16_t acceptedRemoteRid = 0; + uint16_t remoteProtocolVersion = 0; struct sockaddr_storage sa; socklen_t salen; poll_list_t *cons = sock_newPollList(); logadd( LOG_DEBUG2, "Trying to clone %s:%d from %d hosts", name, (int)revision, count ); for (int i = 0; i < count + 5; ++i) { // "i < count + 5" for 5 additional iterations, waiting on pending connects - char *remoteName; + char *remoteName = NULL; + uint64_t remoteImageSize = 0; bool ok = false; int sock; if ( i >= count ) { - sock = sock_multiConnect( cons, NULL, 100, 1000 ); + sock = sock_multiConnect( cons, NULL, 100, _uplinkTimeout ); if ( sock == -2 ) break; } else { if ( log_hasMask( LOG_DEBUG2 ) ) { @@ -1248,7 +1269,7 @@ static dnbd3_image_t *loadImageProxy(char * const name, const uint16_t revision, host[len] = '\0'; logadd( LOG_DEBUG2, "Trying to replicate from %s", host ); } - sock = sock_multiConnect( cons, &servers[i], 100, 1000 ); + sock = sock_multiConnect( cons, &servers[i], 100, _uplinkTimeout ); } if ( sock == -1 || sock == -2 ) continue; salen = sizeof(sa); @@ -1273,7 +1294,11 @@ static dnbd3_image_t *loadImageProxy(char * const name, const uint16_t revision, } else { ok = image_ensureDiskSpace( remoteImageSize + ( 10 * 1024 * 1024 ), false ); // some extra space for cache map etc. } - ok = ok && image_clone( sock, name, remoteRid, remoteImageSize ); // This sets up the file+map+crc and loads the img + if ( ok ) { + ok = image_clone( sock, name, remoteRid, remoteImageSize ); // This sets up the file+map+crc and loads the img + } else { + logadd( LOG_INFO, "Not enough space to replicate '%s:%d'", name, (int)revision ); + } mutex_unlock( &reloadLock ); if ( !ok ) goto server_fail; @@ -1282,26 +1307,32 @@ static dnbd3_image_t *loadImageProxy(char * const name, const uint16_t revision, if ( !sock_sockaddrToDnbd3( (struct sockaddr*)&sa, &uplinkServer ) ) { uplinkServer.type = 0; } - break; + acceptedRemoteRid = remoteRid; + break; // TODO: Maybe we should try the remaining servers if rid == 0, in case there's an even newer one server_fail: ; close( sock ); } sock_destroyPollList( cons ); - // If we still have a pointer to a local image, release the reference - if ( image != NULL ) image_release( image ); + // If we still have a pointer to a local image, compare rid + if ( image != NULL ) { + if ( ( revision == 0 && image->rid >= acceptedRemoteRid ) || ( image->rid == revision ) ) { + return image; + } + // release the reference + image_release( image ); + } // If everything worked out, this call should now actually return the image - image = image_get( name, remoteRid, false ); + image = image_get( name, acceptedRemoteRid, false ); if ( image != NULL && uplinkSock != -1 ) { // If so, init the uplink and pass it the socket - sock_setTimeout( uplinkSock, _uplinkTimeout ); if ( !uplink_init( image, uplinkSock, &uplinkServer, remoteProtocolVersion ) ) { close( uplinkSock ); } else { // Clumsy busy wait, but this should only take as long as it takes to start a thread, so is it really worth using a signalling mechanism? int i = 0; - while ( !image->working && ++i < 100 ) + while ( image->problem.uplink && ++i < 100 ) usleep( 2000 ); } } else if ( uplinkSock != -1 ) { @@ -1318,6 +1349,7 @@ static dnbd3_image_t *loadImageServer(char * const name, const uint16_t requeste { char imageFile[PATHLEN] = ""; uint16_t detectedRid = 0; + bool isLegacyFile = false; if ( requestedRid != 0 ) { snprintf( imageFile, PATHLEN, "%s/%s.r%d", _basePath, name, (int)requestedRid ); @@ -1354,6 +1386,7 @@ static dnbd3_image_t *loadImageServer(char * const name, const uint16_t requeste && ( detectedRid == 0 || !file_isReadable( imageFile ) ) ) { snprintf( imageFile, PATHLEN, "%s/%s", _basePath, name ); detectedRid = 1; + isLegacyFile = true; } logadd( LOG_DEBUG2, "Trying to load %s:%d ( -> %d) as %s", name, (int)requestedRid, (int)detectedRid, imageFile ); // No file was determined, or it doesn't seem to exist/be readable @@ -1361,7 +1394,7 @@ static dnbd3_image_t *loadImageServer(char * const name, const uint16_t requeste logadd( LOG_DEBUG2, "Not found, bailing out" ); return image_get( name, requestedRid, true ); } - if ( !_vmdkLegacyMode && requestedRid == 0 ) { + if ( !isLegacyFile && requestedRid == 0 ) { // rid 0 requested - check if detected rid is readable, decrease rid if not until we reach 0 while ( detectedRid != 0 ) { dnbd3_image_t *image = image_get( name, detectedRid, true ); @@ -1429,9 +1462,13 @@ static bool image_clone(int sock, char *name, uint16_t revision, uint64_t imageS logadd( LOG_WARNING, "OTF-Clone: Corrupted CRC-32 list. ignored. (%s)", name ); } else { int fd = open( crcFile, O_WRONLY | O_CREAT, 0644 ); - write( fd, &masterCrc, sizeof(uint32_t) ); - write( fd, crc32list, crc32len ); + ssize_t ret = write( fd, &masterCrc, sizeof(masterCrc) ); + ret += write( fd, crc32list, crc32len ); close( fd ); + if ( (size_t)ret != crc32len + sizeof(masterCrc) ) { + logadd( LOG_WARNING, "Could not save freshly received crc32 list for %s:%d", name, (int)revision ); + unlink( crcFile ); + } } } free( crc32list ); @@ -1564,14 +1601,23 @@ json_t* image_getListAsJson() ref_put( &uplink->reference ); } - jsonImage = json_pack( "{sisssisisisisI}", + int problems = 0; +#define addproblem(name,val) if (image->problem.name) problems |= (1 << val) + addproblem(read, 0); + addproblem(write, 1); + addproblem(changed, 2); + addproblem(uplink, 3); + addproblem(queue, 4); + + jsonImage = json_pack( "{sisssisisisisIsi}", "id", image->id, // id, name, rid never change, so access them without locking "name", image->name, "rid", (int) image->rid, "users", image->users, "complete", completeness, "idle", idleTime, - "size", (json_int_t)image->virtualFilesize ); + "size", (json_int_t)image->virtualFilesize, + "problems", problems ); if ( bytesReceived != 0 ) { json_object_set_new( jsonImage, "bytesReceived", json_integer( (json_int_t) bytesReceived ) ); } @@ -1594,7 +1640,7 @@ int image_getCompletenessEstimate(dnbd3_image_t * const image) assert( image != NULL ); dnbd3_cache_map_t *cache = ref_get_cachemap( image ); if ( cache == NULL ) - return image->working ? 100 : 0; + return 100; const int len = IMGSIZE_TO_MAPBYTES( image->virtualFilesize ); if ( unlikely( len == 0 ) ) { ref_put( &cache->reference ); @@ -1705,46 +1751,51 @@ bool image_ensureDiskSpaceLocked(uint64_t size, bool force) /** * Make sure at least size bytes are available in _basePath. * Will delete old images to make room for new ones. - * TODO: Store last access time of images. Currently the - * last access time is reset to the file modification time - * on server restart. Thus it will - * currently only delete images if server uptime is > 24 hours. + * It will only delete images if a configurable uptime is + * reached. * This can be overridden by setting force to true, in case * free space is desperately needed. * Return true iff enough space is available. false in random other cases */ static bool image_ensureDiskSpace(uint64_t size, bool force) { - for ( int maxtries = 0; maxtries < 20; ++maxtries ) { + for ( int maxtries = 0; maxtries < 50; ++maxtries ) { uint64_t available; if ( !file_freeDiskSpace( _basePath, NULL, &available ) ) { - logadd( LOG_WARNING, "Could not get free disk space (errno %d), will assume there is enough space left... ;-)\n", errno ); + logadd( LOG_WARNING, "Could not get free disk space (errno %d), will assume there is enough space left.", errno ); return true; } if ( available > size ) return true; // Yay - if ( !_isProxy || _autoFreeDiskSpaceDelay == -1 ) + if ( !_isProxy || _autoFreeDiskSpaceDelay == -1 ) { + logadd( LOG_INFO, "Only %dMiB free, %dMiB requested, but auto-freeing of disk space is disabled.", + (int)(available / (1024ll * 1024)), + (int)(size / (1024ll * 1024)) ); return false; // If not in proxy mode at all, or explicitly disabled, never delete anything + } if ( !force && dnbd3_serverUptime() < (uint32_t)_autoFreeDiskSpaceDelay ) { - logadd( LOG_INFO, "Only %dMiB free, %dMiB requested, but server uptime < %d minutes...", (int)(available / (1024ll * 1024ll)), - (int)(size / (1024 * 1024)), _autoFreeDiskSpaceDelay / 60 ); + logadd( LOG_INFO, "Only %dMiB free, %dMiB requested, but server uptime < %d minutes...", + (int)(available / (1024ll * 1024)), + (int)(size / (1024ll * 1024)), _autoFreeDiskSpaceDelay / 60 ); return false; } - logadd( LOG_INFO, "Only %dMiB free, %dMiB requested, freeing an image...", (int)(available / (1024ll * 1024ll)), - (int)(size / (1024 * 1024)) ); + logadd( LOG_INFO, "Only %dMiB free, %dMiB requested, freeing an image...", + (int)(available / (1024ll * 1024)), + (int)(size / (1024ll * 1024)) ); // Find least recently used image dnbd3_image_t *oldest = NULL; int i; mutex_lock( &imageListLock ); for (i = 0; i < _num_images; ++i) { dnbd3_image_t *current = _images[i]; - if ( current == NULL ) continue; - if ( current->users == 0 ) { // Not in use :-) - if ( oldest == NULL || timing_1le2( ¤t->atime, &oldest->atime ) ) { - // Oldest access time so far - oldest = current; - } - } + if ( current == NULL || current->users != 0 ) + continue; // Empty slot or in use + if ( oldest != NULL && timing_1le2( &oldest->atime, ¤t->atime ) ) + continue; // Already got a newer one + if ( !isImageFromUpstream( current ) ) + continue; // Not replicated, don't touch + // Oldest access time so far + oldest = current; } if ( oldest != NULL ) { oldest->users++; @@ -1760,7 +1811,7 @@ static bool image_ensureDiskSpace(uint64_t size, bool force) image_release( oldest ); // We did users++ above; image might have to be freed entirely return false; } - logadd( LOG_INFO, "'%s:%d' has to go!", oldest->name, (int)oldest->rid ); + logadd( LOG_INFO, "'%s:%d' has to go!", PIMG(oldest) ); char *filename = strdup( oldest->path ); // Copy name as we remove the image first oldest = image_remove( oldest ); // Remove from list first... oldest = image_release( oldest ); // Decrease users counter; if it falls to 0, image will be freed @@ -1790,15 +1841,14 @@ static void* closeUnusedFds(void* nix UNUSED) timing_gets( &deadline, -UNUSED_FD_TIMEOUT ); int fds[FDCOUNT]; int fdindex = 0; + setThreadName( "unused-fd-close" ); mutex_lock( &imageListLock ); for ( int i = 0; i < _num_images; ++i ) { dnbd3_image_t * const image = _images[i]; if ( image == NULL || image->readFd == -1 ) continue; - // TODO: Also close for idle uplinks (uplink_connectionShouldShutdown) - // TODO: And close writeFd for idle uplinks.... if ( image->users == 0 && image->uplinkref == NULL && timing_reached( &image->atime, &deadline ) ) { - logadd( LOG_DEBUG1, "Inactive fd closed for %s:%d", image->name, (int)image->rid ); + logadd( LOG_DEBUG1, "Inactive fd closed for %s:%d", PIMG(image) ); fds[fdindex++] = image->readFd; image->readFd = -1; // Not a race; image->users is 0 and to increase it you need imageListLock if ( fdindex == FDCOUNT ) @@ -1813,6 +1863,177 @@ static void* closeUnusedFds(void* nix UNUSED) return NULL; } +static bool isImageFromUpstream(dnbd3_image_t *image) +{ + if ( !_isProxy ) + return false; // Nothing to do + // Check if we're a "hybrid proxy", i.e. there are only some namespaces (directories) + // for which we have any upstream servers configured. If there's none, don't touch + // the cache map on disk. + if ( !altservers_imageHasAltServers( image->name ) ) + return false; // Nothing to do + return true; +} + +static void* saveLoadAllCacheMaps(void* nix UNUSED) +{ + static ticks nextSave; + declare_now; + bool full = timing_reached( &nextSave, &now ); + time_t walltime = 0; + setThreadName( "cache-mapper" ); + if ( full ) { + walltime = time( NULL ); + // Update at start to avoid concurrent runs + timing_addSeconds( &nextSave, &now, CACHE_MAP_MAX_SAVE_DELAY ); + } + mutex_lock( &imageListLock ); + for ( int i = 0; i < _num_images; ++i ) { + dnbd3_image_t * const image = _images[i]; + if ( image == NULL ) + continue; + image->users++; + mutex_unlock( &imageListLock ); + const bool fromUpstream = isImageFromUpstream( image ); + dnbd3_cache_map_t *cache = ref_get_cachemap( image ); + if ( cache != NULL ) { + if ( fromUpstream ) { + // Replicated image, we're responsible for updating the map, so save it + // Save if dirty bit is set, blocks were invalidated + bool save = cache->dirty; + dnbd3_uplink_t *uplink = ref_get_uplink( &image->uplinkref ); + if ( !save ) { + // Otherwise, consider longer timeout and byte count limits of uplink + if ( uplink != NULL ) { + assert( uplink->bytesReceivedLastSave <= uplink->bytesReceived ); + uint64_t diff = uplink->bytesReceived - uplink->bytesReceivedLastSave; + if ( diff > CACHE_MAP_MAX_UNSAVED_BYTES || ( full && diff != 0 ) ) { + save = true; + } + } + } + if ( save ) { + cache->dirty = false; + if ( uplink != NULL ) { + uplink->bytesReceivedLastSave = uplink->bytesReceived; + } + saveCacheMap( image ); + } + if ( uplink != NULL ) { + ref_put( &uplink->reference ); + } + } else { + // We're not replicating this image, if there's a cache map, reload + // it periodically, since we might read from a shared storage that + // another server instance is writing to. + if ( full || ( !cache->unchanged && !image->problem.read ) ) { + logadd( LOG_DEBUG2, "Reloading cache map of %s:%d", PIMG(image) ); + dnbd3_cache_map_t *onDisk = image_loadCacheMap(image->path, image->virtualFilesize); + if ( onDisk == NULL ) { + // Should be complete now + logadd( LOG_DEBUG1, "External replication of %s:%d complete", PIMG(image) ); + ref_setref( &image->ref_cacheMap, NULL ); + } else { + const int mapSize = IMGSIZE_TO_MAPBYTES( image->virtualFilesize ); + if ( memcmp( cache->map, onDisk->map, mapSize ) == 0 ) { + // Unchanged + cache->unchanged = true; + onDisk->reference.free( &onDisk->reference ); + } else { + // Replace + ref_setref( &image->ref_cacheMap, &onDisk->reference ); + logadd( LOG_DEBUG2, "Map changed" ); + } + } + } + } // end reload cache map + ref_put( &cache->reference ); + } // end has cache map + if ( full && fromUpstream ) { + saveMetaData( image, &now, walltime ); + } + image_release( image ); // Always do this instead of users-- to handle freeing + mutex_lock( &imageListLock ); + } + mutex_unlock( &imageListLock ); + return NULL; +} + +/** + * Saves the cache map of the given image. + * Return false if this image doesn't have a cache map, or if the image + * doesn't have any uplink to replicate from. In this case the image might + * still have a cache map that was loaded from disk, and should be reloaded + * periodically. + * @param image the image + */ +static void saveCacheMap(dnbd3_image_t *image) +{ + dnbd3_cache_map_t *cache = ref_get_cachemap( image ); + if ( cache == NULL ) + return; // Race - wasn't NULL in function call above... + + logadd( LOG_DEBUG2, "Saving cache map of %s:%d", PIMG(image) ); + const size_t size = IMGSIZE_TO_MAPBYTES(image->virtualFilesize); + char mapfile[strlen( image->path ) + 4 + 1]; + strcpy( mapfile, image->path ); + strcat( mapfile, ".map" ); + + int fd = open( mapfile, O_WRONLY | O_CREAT, 0644 ); + if ( fd == -1 ) { + const int err = errno; + ref_put( &cache->reference ); + logadd( LOG_WARNING, "Could not open file to write cache map to disk (errno=%d) file %s", err, mapfile ); + return; + } + + // On Linux we could use readFd, but in general it's not guaranteed to work + int imgFd = open( image->path, O_WRONLY ); + if ( imgFd == -1 ) { + logadd( LOG_WARNING, "Cannot open %s for fsync(): errno=%d", image->path, errno ); + } else { + if ( fsync( imgFd ) == -1 ) { + logadd( LOG_ERROR, "fsync() on image file %s failed with errno %d. Resetting cache map.", image->path, errno ); + dnbd3_cache_map_t *old = image_loadCacheMap(image->path, image->virtualFilesize); + const int mapSize = IMGSIZE_TO_MAPBYTES( image->virtualFilesize ); + if ( old == NULL ) { + // Could not load old map. FS might be toast. + logadd( LOG_ERROR, "Cannot load old cache map. Setting all zero." ); + memset( cache->map, 0, mapSize ); + } else { + // AND the maps together to be safe + for ( int i = 0; i < mapSize; ++i ) { + cache->map[i] &= old->map[i]; + } + old->reference.free( &old->reference ); + } + } + close( imgFd ); + } + + // Write current map to file + size_t done = 0; + while ( done < size ) { + const ssize_t ret = write( fd, cache->map + done, size - done ); + if ( ret == -1 ) { + if ( errno == EINTR ) continue; + logadd( LOG_WARNING, "Could not write cache map (errno=%d) file %s", errno, mapfile ); + break; + } + if ( ret <= 0 ) { + logadd( LOG_WARNING, "Unexpected return value %d for write() to %s", (int)ret, mapfile ); + break; + } + done += (size_t)ret; + } + ref_put( &cache->reference ); + if ( fsync( fd ) == -1 ) { + logadd( LOG_WARNING, "fsync() on image map %s failed with errno %d", mapfile, errno ); + } + close( fd ); + // TODO fsync on parent directory +} + static void allocCacheMap(dnbd3_image_t *image, bool complete) { const uint8_t val = complete ? 0xff : 0; @@ -1822,7 +2043,7 @@ static void allocCacheMap(dnbd3_image_t *image, bool complete) memset( cache->map, val, byteSize ); mutex_lock( &image->lock ); if ( image->ref_cacheMap != NULL ) { - logadd( LOG_WARNING, "BUG: allocCacheMap called but there already is a cache map for %s:%d", image->name, (int)image->rid ); + logadd( LOG_WARNING, "BUG: allocCacheMap called but there already is a map for %s:%d", PIMG(image) ); free( cache ); } else { ref_setref( &image->ref_cacheMap, &cache->reference ); @@ -1830,3 +2051,77 @@ static void allocCacheMap(dnbd3_image_t *image, bool complete) mutex_unlock( &image->lock ); } +/** + * It's assumed you hold a reference to the image + */ +static void saveMetaData(dnbd3_image_t *image, ticks *now, time_t walltime) +{ + if ( !image->accessed ) + return; + ticks tmp; + uint32_t diff; + char *fn; + if ( asprintf( &fn, "%s.meta", image->path ) == -1 ) { + logadd( LOG_WARNING, "Cannot asprintf meta" ); + return; + } + if ( now == NULL ) { + timing_get( &tmp ); + now = &tmp; + walltime = time( NULL ); + } + mutex_lock( &image->lock ); + image->accessed = false; + diff = timing_diff( &image->atime, now ); + mutex_unlock( &image->lock ); + FILE *f = fopen( fn, "w" ); + if ( f == NULL ) { + logadd( LOG_WARNING, "Cannot open %s for writing", fn ); + } else { + fprintf( f, "[main]\natime=%"PRIu64"\n", (uint64_t)( walltime - diff ) ); + fclose( f ); + } + free( fn ); + // TODO: fsync() dir +} + +static void loadImageMeta(dnbd3_image_t *image) +{ + int32_t offset = 1; + char *fn; + if ( asprintf( &fn, "%s.meta", image->path ) == -1 ) { + logadd( LOG_WARNING, "asprintf load" ); + } else { + int fh = open( fn, O_RDONLY ); + free( fn ); + if ( fh != -1 ) { + char buf[200]; + ssize_t ret = read( fh, buf, sizeof(buf)-1 ); + close( fh ); + if ( ret > 0 ) { + buf[ret] = '\0'; + // Do it the cheap way until we actually store more stuff + char *pos = strstr( buf, "atime=" ); + if ( pos != NULL ) { + offset = (int32_t)( atol( pos + 6 ) - time( NULL ) ); + } + } + } + } + if ( offset == 1 ) { + // Nothing from .meta file, use old guesstimate + struct stat st; + if ( stat( image->path, &st ) == 0 ) { + // Negatively offset atime by file modification time + offset = (int32_t)( st.st_mtime - time( NULL ) ); + } else { + offset = 0; + } + image->accessed = true; + } + if ( offset > 0 ) { + offset = 0; + } + timing_gets( &image->atime, offset ); +} + |