diff options
| -rw-r--r-- | source3/smbd/fileio.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/source3/smbd/fileio.c b/source3/smbd/fileio.c index 92b7d3ed9e..92757f7052 100644 --- a/source3/smbd/fileio.c +++ b/source3/smbd/fileio.c @@ -796,6 +796,26 @@ n = %u, wcp->offset=%.0f, wcp->data_size=%u\n", DO_PROFILE_INC(writecache_init_writes); } #endif + + if ((wcp->data_size == 0) + && (pos > wcp->file_size) + && (pos + n <= wcp->file_size + wcp->alloc_size)) { + /* + * This is a write completely beyond the + * current EOF, but within reach of the write + * cache. We expect fill-up writes pretty + * soon, so it does not make sense to start + * the write cache at the current + * offset. These fill-up writes would trigger + * separate pwrites or even unnecessary cache + * flushes because they overlap if this is a + * one-byte allocating write. + */ + wcp->offset = wcp->file_size; + wcp->data_size = pos - wcp->file_size; + memset(wcp->data, 0, wcp->data_size); + } + memcpy(wcp->data+wcp->data_size, data, n); if (wcp->data_size == 0) { wcp->offset = pos; |