diff options
author | Peter Lieven <pl@kamp.de> | 2015-11-17 15:06:25 -0500 |
---|---|---|
committer | John Snow <jsnow@redhat.com> | 2015-11-17 15:06:25 -0500 |
commit | 1d8c11d631545ee43aff16b0763aff7181b61f20 (patch) | |
tree | 8606957a184aa43146edb7771e3c1966d24ce1e4 /hw/ide/internal.h | |
parent | ca78ecfa72f311cd647b12a41d93e1ce54f18e66 (diff) |
ide: add support for IDEBufferedRequest
this patch adds a new aio readv compatible function which copies
all data through a bounce buffer. These buffered requests can be
flagged as orphaned which means that their original callback has
already been invoked and the request has just not been completed
by the backend storage. The bounce buffer guarantees that guest
memory corruption is avoided when such a orphaned request is
completed by the backend at a later stage.
This trick only works for read requests as a write request completed
at a later stage might corrupt data as there is no way to control
if and what data has already been written to the storage.
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1447345846-15624-4-git-send-email-pl@kamp.de
Signed-off-by: John Snow <jsnow@redhat.com>
Diffstat (limited to 'hw/ide/internal.h')
-rw-r--r-- | hw/ide/internal.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/hw/ide/internal.h b/hw/ide/internal.h index e4629b023a..2d1e2d2d2f 100644 --- a/hw/ide/internal.h +++ b/hw/ide/internal.h @@ -343,6 +343,16 @@ enum ide_dma_cmd { #define ide_cmd_is_read(s) \ ((s)->dma_cmd == IDE_DMA_READ) +typedef struct IDEBufferedRequest { + QLIST_ENTRY(IDEBufferedRequest) list; + struct iovec iov; + QEMUIOVector qiov; + QEMUIOVector *original_qiov; + BlockCompletionFunc *original_cb; + void *original_opaque; + bool orphaned; +} IDEBufferedRequest; + /* NOTE: IDEState represents in fact one drive */ struct IDEState { IDEBus *bus; @@ -396,6 +406,7 @@ struct IDEState { BlockAIOCB *pio_aiocb; struct iovec iov; QEMUIOVector qiov; + QLIST_HEAD(, IDEBufferedRequest) buffered_requests; /* ATA DMA state */ uint64_t io_buffer_offset; int32_t io_buffer_size; @@ -572,6 +583,9 @@ void ide_set_inactive(IDEState *s, bool more); BlockAIOCB *ide_issue_trim(BlockBackend *blk, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); +BlockAIOCB *ide_buffered_readv(IDEState *s, int64_t sector_num, + QEMUIOVector *iov, int nb_sectors, + BlockCompletionFunc *cb, void *opaque); /* hw/ide/atapi.c */ void ide_atapi_cmd(IDEState *s); |