Am 19.05.2011 10:58, schrieb Christoph Hellwig:
> Add support for TRIM sub function of the data set management command,
> and wire it up to the qemu discard infrastructure.
>
> Signed-off-by: Christoph Hellwig <h...@lst.de>
>
> Index: qemu/hw/ide/core.c
> ===================================================================
> --- qemu.orig/hw/ide/core.c 2011-05-18 20:30:20.855172933 +0200
> +++ qemu/hw/ide/core.c 2011-05-18 20:32:26.237625024 +0200
> @@ -124,6 +124,9 @@ static void ide_identify(IDEState *s)
> put_le16(p + 66, 120);
> put_le16(p + 67, 120);
> put_le16(p + 68, 120);
> + if (dev && dev->conf.discard_granularity) {
> + put_le16(p + 69, (1 << 14)); /* determinate TRIM behavior */
> + }
>
> if (s->ncq_queues) {
> put_le16(p + 75, s->ncq_queues - 1);
> @@ -157,6 +160,9 @@ static void ide_identify(IDEState *s)
> dev = s->unit ? s->bus->slave : s->bus->master;
> if (dev && dev->conf.physical_block_size)
> put_le16(p + 106, 0x6000 | get_physical_block_exp(&dev->conf));
> + if (dev && dev->conf.discard_granularity) {
> + put_le16(p + 169, 1); /* TRIM support */
> + }
>
> memcpy(s->identify_data, p, sizeof(s->identify_data));
> s->identify_set = 1;
> @@ -299,6 +305,72 @@ static void ide_set_signature(IDEState *
> }
> }
>
> +typedef struct TrimAIOCB {
> + BlockDriverAIOCB common;
> + QEMUBH *bh;
> + int ret;
> +} TrimAIOCB;
> +
> +static void trim_aio_cancel(BlockDriverAIOCB *acb)
> +{
> + TrimAIOCB *iocb = container_of(acb, TrimAIOCB, common);
> +
> + qemu_bh_delete(iocb->bh);
> + iocb->bh = NULL;
> + qemu_aio_release(iocb);
> +}
> +
> +static AIOPool trim_aio_pool = {
> + .aiocb_size = sizeof(TrimAIOCB),
> + .cancel = trim_aio_cancel,
> +};
> +
> +static void ide_trim_bh_cb(void *opaque)
> +{
> + TrimAIOCB *iocb = opaque;
> +
> + iocb->common.cb(iocb->common.opaque, iocb->ret);
> +
> + qemu_bh_delete(iocb->bh);
> + iocb->bh = NULL;
> +
> + qemu_aio_release(iocb);
> +}
> +
> +BlockDriverAIOCB *ide_issue_trim(BlockDriverState *bs,
> + int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
> + BlockDriverCompletionFunc *cb, void *opaque)
> +{
> + TrimAIOCB *iocb;
> + int i, j, ret;
> +
> + iocb = qemu_aio_get(&trim_aio_pool, bs, cb, opaque);
> + iocb->bh = qemu_bh_new(ide_trim_bh_cb, iocb);
> + iocb->ret = 0;
> +
> + for (j = 0; j < qiov->niov; j++) {
> + uint64_t *buffer = qiov->iov[j].iov_base;
> +
> + for (i = 0; i < qiov->iov[j].iov_len / 8; i++) {
> + /* 6-byte LBA + 2-byte range per entry */
> + uint64_t entry = le64_to_cpu(buffer[i]);
> + uint64_t sector = entry & 0x0000ffffffffffffULL;
> + uint16_t count = entry >> 48;
> +
> + if (count == 0)
> + break;
> +
> + ret = bdrv_discard(bs, sector * 512, count * 512);
Hm... bdrv_discard wants sector numbers instead of bytes, doesn't it?
If you agree, I'll send out and apply a fixed and rebased version.
Kevin
