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| author | Eric Farman <farman@linux.ibm.com> | 2022-10-21 18:02:48 +0300 |
|---|---|---|
| committer | Heiko Carstens <hca@linux.ibm.com> | 2023-01-09 16:34:08 +0300 |
| commit | 61783394f4eb3a8a0944005ea2761c011788a9c3 (patch) | |
| tree | a96479ffcfb2be7092010909f69ae4b3b945bc2a /drivers/s390/cio | |
| parent | 62a97a56a64c97c3865e55d702babc22f3b2ea6a (diff) | |
| download | linux-61783394f4eb3a8a0944005ea2761c011788a9c3.tar.xz | |
vfio/ccw: populate page_array struct inline
There are two possible ways the list of addresses that get passed
to vfio are calculated. One is from a guest IDAL, which would be
an array of (probably) non-contiguous addresses. The other is
built from contiguous pages that follow the starting address
provided by ccw->cda.
page_array_alloc() attempts to simplify things by pre-populating
this array from the starting address, but that's not needed for
a CCW with an IDAL anyway so doesn't need to be in the allocator.
Move it to the caller in the non-IDAL case, since it will be
overwritten when reading the guest IDAL.
Remove the initialization of the pa_page output pointers,
since it won't be explicitly needed for either case.
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Diffstat (limited to 'drivers/s390/cio')
| -rw-r--r-- | drivers/s390/cio/vfio_ccw_cp.c | 22 |
1 files changed, 5 insertions, 17 deletions
diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index b1436736b7b6..f448aa93007f 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -42,7 +42,6 @@ struct ccwchain { /* * page_array_alloc() - alloc memory for page array * @pa: page_array on which to perform the operation - * @iova: target guest physical address * @len: number of pages that should be pinned from @iova * * Attempt to allocate memory for page array. @@ -56,10 +55,8 @@ struct ccwchain { * -EINVAL if pa->pa_nr is not initially zero, or pa->pa_iova is not NULL * -ENOMEM if alloc failed */ -static int page_array_alloc(struct page_array *pa, u64 iova, unsigned int len) +static int page_array_alloc(struct page_array *pa, unsigned int len) { - int i; - if (pa->pa_nr || pa->pa_iova) return -EINVAL; @@ -78,13 +75,6 @@ static int page_array_alloc(struct page_array *pa, u64 iova, unsigned int len) return -ENOMEM; } - pa->pa_iova[0] = iova; - pa->pa_page[0] = NULL; - for (i = 1; i < pa->pa_nr; i++) { - pa->pa_iova[i] = pa->pa_iova[i - 1] + PAGE_SIZE; - pa->pa_page[i] = NULL; - } - return 0; } @@ -548,7 +538,7 @@ static int ccwchain_fetch_ccw(struct ccw1 *ccw, * required for the data transfer, since we only only support * 4K IDAWs today. */ - ret = page_array_alloc(pa, iova, idaw_nr); + ret = page_array_alloc(pa, idaw_nr); if (ret < 0) goto out_free_idaws; @@ -565,11 +555,9 @@ static int ccwchain_fetch_ccw(struct ccw1 *ccw, for (i = 0; i < idaw_nr; i++) pa->pa_iova[i] = idaws[i]; } else { - /* - * No action is required here; the iova addresses in page_array - * were initialized sequentially in page_array_alloc() beginning - * with the contents of ccw->cda. - */ + pa->pa_iova[0] = iova; + for (i = 1; i < pa->pa_nr; i++) + pa->pa_iova[i] = pa->pa_iova[i - 1] + PAGE_SIZE; } if (ccw_does_data_transfer(ccw)) { |