vfio/pds: Move seq/ack bitmaps into region struct

Since the host seq/ack bitmaps are part of a region
move them into struct pds_vfio_region. Also, make use
of the bmp_bytes value for validation purposes.

Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
Link: https://lore.kernel.org/r/20231117001207.2793-6-brett.creeley@amd.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Author: brettcreeley

drivers/vfio/pci/pds/dirty.c

@@ -85,18 +85,20 @@ static int pds_vfio_dirty_alloc_bitmaps(struct pds_vfio_dirty *dirty,
 		return -ENOMEM;
 	}
 
-	dirty->region.host_seq.bmp = host_seq_bmp;
-	dirty->region.host_ack.bmp = host_ack_bmp;
+	dirty->region.host_seq = host_seq_bmp;
+	dirty->region.host_ack = host_ack_bmp;
+	dirty->region.bmp_bytes = bytes;
 
 	return 0;
 }
 
 static void pds_vfio_dirty_free_bitmaps(struct pds_vfio_dirty *dirty)
 {
-	vfree(dirty->region.host_seq.bmp);
-	vfree(dirty->region.host_ack.bmp);
-	dirty->region.host_seq.bmp = NULL;
-	dirty->region.host_ack.bmp = NULL;
+	vfree(dirty->region.host_seq);
+	vfree(dirty->region.host_ack);
+	dirty->region.host_seq = NULL;
+	dirty->region.host_ack = NULL;
+	dirty->region.bmp_bytes = 0;
 }
 
 static void __pds_vfio_dirty_free_sgl(struct pds_vfio_pci_device *pds_vfio,
@@ -301,8 +303,8 @@ void pds_vfio_dirty_disable(struct pds_vfio_pci_device *pds_vfio, bool send_cmd)
 
 static int pds_vfio_dirty_seq_ack(struct pds_vfio_pci_device *pds_vfio,
 				  struct pds_vfio_region *region,
-				  struct pds_vfio_bmp_info *bmp_info,
-				  u32 offset, u32 bmp_bytes, bool read_seq)
+				  unsigned long *seq_ack_bmp, u32 offset,
+				  u32 bmp_bytes, bool read_seq)
 {
 	const char *bmp_type_str = read_seq ? "read_seq" : "write_ack";
 	u8 dma_dir = read_seq ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
@@ -319,7 +321,7 @@ static int pds_vfio_dirty_seq_ack(struct pds_vfio_pci_device *pds_vfio,
 	int err;
 	int i;
 
-	bmp = (void *)((u64)bmp_info->bmp + offset);
+	bmp = (void *)((u64)seq_ack_bmp + offset);
 	page_offset = offset_in_page(bmp);
 	bmp -= page_offset;
 
@@ -387,15 +389,15 @@ static int pds_vfio_dirty_write_ack(struct pds_vfio_pci_device *pds_vfio,
 				    u32 offset, u32 len)
 {
 
-	return pds_vfio_dirty_seq_ack(pds_vfio, region, &region->host_ack,
+	return pds_vfio_dirty_seq_ack(pds_vfio, region, region->host_ack,
 				      offset, len, WRITE_ACK);
 }
 
 static int pds_vfio_dirty_read_seq(struct pds_vfio_pci_device *pds_vfio,
 				   struct pds_vfio_region *region,
 				   u32 offset, u32 len)
 {
-	return pds_vfio_dirty_seq_ack(pds_vfio, region, &region->host_seq,
+	return pds_vfio_dirty_seq_ack(pds_vfio, region, region->host_seq,
 				      offset, len, READ_SEQ);
 }
 
@@ -411,8 +413,8 @@ static int pds_vfio_dirty_process_bitmaps(struct pds_vfio_pci_device *pds_vfio,
 	int dword_count;
 
 	dword_count = len_bytes / sizeof(u64);
-	seq = (__le64 *)((u64)region->host_seq.bmp + bmp_offset);
-	ack = (__le64 *)((u64)region->host_ack.bmp + bmp_offset);
+	seq = (__le64 *)((u64)region->host_seq + bmp_offset);
+	ack = (__le64 *)((u64)region->host_ack + bmp_offset);
 	bmp_offset_bit = bmp_offset * 8;
 
 	for (int i = 0; i < dword_count; i++) {
@@ -479,6 +481,13 @@ static int pds_vfio_dirty_sync(struct pds_vfio_pci_device *pds_vfio,
 		return -EINVAL;
 	}
 
+	if (bmp_bytes > region->bmp_bytes) {
+		dev_err(dev,
+			"Calculated bitmap bytes %llu larger than region's cached bmp_bytes %llu\n",
+			bmp_bytes, region->bmp_bytes);
+		return -EINVAL;
+	}
+
 	bmp_offset = DIV_ROUND_UP((iova - region->start) /
 				  region->page_size, sizeof(u64));
 

drivers/vfio/pci/pds/dirty.h

@@ -4,14 +4,10 @@
 #ifndef _DIRTY_H_
 #define _DIRTY_H_
 
-struct pds_vfio_bmp_info {
-	unsigned long *bmp;
-	u32 bmp_bytes;
-};
-
 struct pds_vfio_region {
-	struct pds_vfio_bmp_info host_seq;
-	struct pds_vfio_bmp_info host_ack;
+	unsigned long *host_seq;
+	unsigned long *host_ack;
+	u64 bmp_bytes;
 	u64 size;
 	u64 start;
 	u64 page_size;