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| author | Simon Rettberg | 2024-05-23 17:05:37 +0200 |
|---|---|---|
| committer | Simon Rettberg | 2024-05-23 17:05:37 +0200 |
| commit | bbb5333f411001e3922cc87d7c0c5b3d9e7bdb12 (patch) | |
| tree | 35ec51526c3e731975b8054dcef1b8f2141a804b | |
| parent | [FUSE] cow: Fix lowercasing of header field (diff) | |
| download | dnbd3-bbb5333f411001e3922cc87d7c0c5b3d9e7bdb12.tar.gz dnbd3-bbb5333f411001e3922cc87d7c0c5b3d9e7bdb12.tar.xz dnbd3-bbb5333f411001e3922cc87d7c0c5b3d9e7bdb12.zip | |
[FUSE] curl: Handle read callbacks with < 4k buffer size
| -rw-r--r-- | src/fuse/cowfile.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/fuse/cowfile.c b/src/fuse/cowfile.c index a0d4443..a5d6e4d 100644 --- a/src/fuse/cowfile.c +++ b/src/fuse/cowfile.c @@ -261,6 +261,10 @@ static size_t curlReadCallbackUploadBlock( char *ptr, size_t size, size_t nmemb, { cow_curl_read_upload_t *uploadBlock = (cow_curl_read_upload_t *)userdata; size_t len = 0; + + if ( size * nmemb < DNBD3_BLOCK_SIZE ) { + logadd( LOG_INFO, "Wow, curl read callback with %d bytes left", (int)( size * nmemb ) ); + } // Check if we're still in the bitfield if ( uploadBlock->position < COW_BITFIELD_SIZE ) { size_t lenCpy = MIN( COW_BITFIELD_SIZE - uploadBlock->position, size * nmemb ); @@ -276,8 +280,9 @@ static size_t curlReadCallbackUploadBlock( char *ptr, size_t size, size_t nmemb, ssize_t spaceLeft = ( size * nmemb ) - len; // Only read blocks that have been written to the cluster. Saves bandwidth. Not optimal since // we do a lot of 4k/32k reads, but it's not that performance critical I guess... - while ( spaceLeft >= (ssize_t)DNBD3_BLOCK_SIZE && inClusterOffset < (off_t)COW_DATA_CLUSTER_SIZE ) { + while ( spaceLeft > 0 && inClusterOffset < (off_t)COW_DATA_CLUSTER_SIZE ) { int bitNumber = (int)( inClusterOffset / DNBD3_BLOCK_SIZE ); + uint32_t blockOffset = (uint32_t)( inClusterOffset % DNBD3_BLOCK_SIZE ); size_t readSize; // Small performance hack: All bits one in a byte, do a 32k instead of 4k read // TODO: preadv with a large iov, reading unchanged blocks into a trash-buffer @@ -288,8 +293,13 @@ static size_t curlReadCallbackUploadBlock( char *ptr, size_t size, size_t nmemb, } else { readSize = DNBD3_BLOCK_SIZE; } + readSize -= blockOffset; + if ( (ssize_t)readSize > spaceLeft ) { + readSize = spaceLeft; + } // If handling single block, check bits in our copy, as global bitfield could change - if ( readSize != DNBD3_BLOCK_SIZE || checkBit( uploadBlock->bitfield, bitNumber ) ) { + // If uploading 8 blocks at once, check already happened above + if ( readSize > DNBD3_BLOCK_SIZE || checkBit( uploadBlock->bitfield, bitNumber ) ) { ssize_t lengthRead = pread( cow.fdData, ( ptr + len ), readSize, uploadBlock->cluster->offset + inClusterOffset ); if ( lengthRead == -1 ) { |