6.6-stable review patch. If anyone has any objections, please let me know.
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From: Yishai Hadas yishaih@nvidia.com
[ Upstream commit 9c7c5430bca36e9636eabbba0b3b53251479c7ab ]
Align the page tracking maximum message size with the device's capability instead of relying on PAGE_SIZE.
This adjustment resolves a mismatch on systems where PAGE_SIZE is 64K, but the firmware only supports a maximum message size of 4K.
Now that we rely on the device's capability for max_message_size, we must account for potential future increases in its value.
Key considerations include: - Supporting message sizes that exceed a single system page (e.g., an 8K message on a 4K system). - Ensuring the RQ size is adjusted to accommodate at least 4 WQEs/messages, in line with the device specification.
The above has been addressed as part of the patch.
Fixes: 79c3cf279926 ("vfio/mlx5: Init QP based resources for dirty tracking") Reviewed-by: Cédric Le Goater clg@redhat.com Tested-by: Yingshun Cui yicui@redhat.com Signed-off-by: Yishai Hadas yishaih@nvidia.com Link: https://lore.kernel.org/r/20241205122654.235619-1-yishaih@nvidia.com Signed-off-by: Alex Williamson alex.williamson@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/vfio/pci/mlx5/cmd.c | 47 +++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 12 deletions(-)
diff --git a/drivers/vfio/pci/mlx5/cmd.c b/drivers/vfio/pci/mlx5/cmd.c index 33574b04477da..2d996c913ecd5 100644 --- a/drivers/vfio/pci/mlx5/cmd.c +++ b/drivers/vfio/pci/mlx5/cmd.c @@ -1368,7 +1368,8 @@ int mlx5vf_start_page_tracker(struct vfio_device *vdev, struct mlx5_vhca_qp *host_qp; struct mlx5_vhca_qp *fw_qp; struct mlx5_core_dev *mdev; - u32 max_msg_size = PAGE_SIZE; + u32 log_max_msg_size; + u32 max_msg_size; u64 rq_size = SZ_2M; u32 max_recv_wr; int err; @@ -1385,6 +1386,12 @@ int mlx5vf_start_page_tracker(struct vfio_device *vdev, }
mdev = mvdev->mdev; + log_max_msg_size = MLX5_CAP_ADV_VIRTUALIZATION(mdev, pg_track_log_max_msg_size); + max_msg_size = (1ULL << log_max_msg_size); + /* The RQ must hold at least 4 WQEs/messages for successful QP creation */ + if (rq_size < 4 * max_msg_size) + rq_size = 4 * max_msg_size; + memset(tracker, 0, sizeof(*tracker)); tracker->uar = mlx5_get_uars_page(mdev); if (IS_ERR(tracker->uar)) { @@ -1474,25 +1481,41 @@ set_report_output(u32 size, int index, struct mlx5_vhca_qp *qp, { u32 entry_size = MLX5_ST_SZ_BYTES(page_track_report_entry); u32 nent = size / entry_size; + u32 nent_in_page; + u32 nent_to_set; struct page *page; + u32 page_offset; + u32 page_index; + u32 buf_offset; + void *kaddr; u64 addr; u64 *buf; int i;
- if (WARN_ON(index >= qp->recv_buf.npages || + buf_offset = index * qp->max_msg_size; + if (WARN_ON(buf_offset + size >= qp->recv_buf.npages * PAGE_SIZE || (nent > qp->max_msg_size / entry_size))) return;
- page = qp->recv_buf.page_list[index]; - buf = kmap_local_page(page); - for (i = 0; i < nent; i++) { - addr = MLX5_GET(page_track_report_entry, buf + i, - dirty_address_low); - addr |= (u64)MLX5_GET(page_track_report_entry, buf + i, - dirty_address_high) << 32; - iova_bitmap_set(dirty, addr, qp->tracked_page_size); - } - kunmap_local(buf); + do { + page_index = buf_offset / PAGE_SIZE; + page_offset = buf_offset % PAGE_SIZE; + nent_in_page = (PAGE_SIZE - page_offset) / entry_size; + page = qp->recv_buf.page_list[page_index]; + kaddr = kmap_local_page(page); + buf = kaddr + page_offset; + nent_to_set = min(nent, nent_in_page); + for (i = 0; i < nent_to_set; i++) { + addr = MLX5_GET(page_track_report_entry, buf + i, + dirty_address_low); + addr |= (u64)MLX5_GET(page_track_report_entry, buf + i, + dirty_address_high) << 32; + iova_bitmap_set(dirty, addr, qp->tracked_page_size); + } + kunmap_local(kaddr); + buf_offset += (nent_to_set * entry_size); + nent -= nent_to_set; + } while (nent); }
static void