Merge patch series "scsi: aacraid: struct sgmap: Replace 1-element arrays with flexible arrays"

Kees Cook <[e-mail]> says:

This replaces some of the last remaining uses in the kernel of
1-element "fake" flexible arrays with modern C99 flexible arrays. Some
refactoring is done to ease this, and binary differences are
identified. For the on stack size changes in patch 2, the "yes, that
is the source of the binary differences" debugging patch can be found
here[1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git/commit/?h=dev/v6.10-rc2/1-element&id=45e6226bcbc5e982541754eca7ac29f403e82f5e

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Martin K. Petersen <[e-mail]>

drivers/scsi/aacraid/aachba.c

···
 			return ret;
 		command = ContainerRawIo;
 		fibsize = sizeof(struct aac_raw_io) +
-			((le32_to_cpu(readcmd->sg.count)-1) * sizeof(struct sgentryraw));
+			(le32_to_cpu(readcmd->sg.count) * sizeof(struct sgentryraw));
 	}
 
 	BUG_ON(fibsize > (fib->dev->max_fib_size - sizeof(struct aac_fibhdr)));
···
 	if (ret < 0)
 		return ret;
 	fibsize = sizeof(struct aac_read64) +
-		((le32_to_cpu(readcmd->sg.count) - 1) *
+		(le32_to_cpu(readcmd->sg.count) *
 		 sizeof (struct sgentry64));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
···
 	if (ret < 0)
 		return ret;
 	fibsize = sizeof(struct aac_read) +
-			((le32_to_cpu(readcmd->sg.count) - 1) *
+			(le32_to_cpu(readcmd->sg.count) *
 			 sizeof (struct sgentry));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
···
 			return ret;
 		command = ContainerRawIo;
 		fibsize = sizeof(struct aac_raw_io) +
-			((le32_to_cpu(writecmd->sg.count)-1) * sizeof (struct sgentryraw));
+			(le32_to_cpu(writecmd->sg.count) * sizeof(struct sgentryraw));
 	}
 
 	BUG_ON(fibsize > (fib->dev->max_fib_size - sizeof(struct aac_fibhdr)));
···
 	if (ret < 0)
 		return ret;
 	fibsize = sizeof(struct aac_write64) +
-		((le32_to_cpu(writecmd->sg.count) - 1) *
+		(le32_to_cpu(writecmd->sg.count) *
 		 sizeof (struct sgentry64));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
···
 	if (ret < 0)
 		return ret;
 	fibsize = sizeof(struct aac_write) +
-		((le32_to_cpu(writecmd->sg.count) - 1) *
+		(le32_to_cpu(writecmd->sg.count) *
 		 sizeof (struct sgentry));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
···
 	/*
 	 *	Build Scatter/Gather list
 	 */
-	fibsize = sizeof (struct aac_srb) - sizeof (struct sgentry) +
+	fibsize = sizeof(struct aac_srb) +
 		((le32_to_cpu(srbcmd->sg.count) & 0xff) *
-		 sizeof (struct sgentry64));
+		 sizeof(struct sgentry64));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
 
···
 	 *	Build Scatter/Gather list
 	 */
 	fibsize = sizeof (struct aac_srb) +
-		(((le32_to_cpu(srbcmd->sg.count) & 0xff) - 1) *
+		((le32_to_cpu(srbcmd->sg.count) & 0xff) *
 		 sizeof (struct sgentry));
 	BUG_ON (fibsize > (fib->dev->max_fib_size -
 				sizeof(struct aac_fibhdr)));
···
 	fibptr->hw_fib_va->header.XferState &=
 		~cpu_to_le32(FastResponseCapable);
 
-	fibsize  = sizeof(struct aac_srb) - sizeof(struct sgentry) +
-						sizeof(struct sgentry64);
+	fibsize = sizeof(struct aac_srb) + sizeof(struct sgentry64);
 
 	/* allocate DMA buffer for response */
 	addr = dma_map_single(&dev->pdev->dev, xfer_buf, xfer_len,
···
 		dev->a_ops.adapter_bounds = aac_bounds_32;
 		dev->scsi_host_ptr->sg_tablesize = (dev->max_fib_size -
 			sizeof(struct aac_fibhdr) -
-			sizeof(struct aac_write) + sizeof(struct sgentry)) /
+			sizeof(struct aac_write)) /
 				sizeof(struct sgentry);
 		if (dev->dac_support) {
 			dev->a_ops.adapter_read = aac_read_block64;
···
 			dev->scsi_host_ptr->sg_tablesize =
 				(dev->max_fib_size -
 				sizeof(struct aac_fibhdr) -
-				sizeof(struct aac_write64) +
-				sizeof(struct sgentry64)) /
+				sizeof(struct aac_write64)) /
 					sizeof(struct sgentry64);
 		} else {
 			dev->a_ops.adapter_read = aac_read_block;

drivers/scsi/aacraid/aacraid.h

···
 
 struct sgmap {
 	__le32		count;
-	struct sgentry	sg[1];
+	struct sgentry	sg[];
 };
 
 struct user_sgmap {
 	u32		count;
-	struct user_sgentry	sg[1];
+	struct user_sgentry	sg[];
 };
 
 struct sgmap64 {
 	__le32		count;
-	struct sgentry64 sg[1];
+	struct sgentry64 sg[];
 };
 
 struct user_sgmap64 {
 	u32		count;
-	struct user_sgentry64 sg[1];
+	struct user_sgentry64 sg[];
 };
 
 struct sgmapraw {
 	__le32		  count;
-	struct sgentryraw sg[1];
-};
-
-struct user_sgmapraw {
-	u32		  count;
-	struct user_sgentryraw sg[1];
+	struct sgentryraw sg[];
 };
 
 struct creation_info
···
 };
 
 struct aac_srb_unit {
-	struct aac_srb		srb;
 	struct aac_srb_reply	srb_reply;
+	struct aac_srb		srb;
 };
 
 /*

drivers/scsi/aacraid/commctrl.c

···
 		goto cleanup;
 	}
 
-	if ((fibsize < (sizeof(struct user_aac_srb) - sizeof(struct user_sgentry))) ||
+	if ((fibsize < sizeof(struct user_aac_srb)) ||
 	    (fibsize > (dev->max_fib_size - sizeof(struct aac_fibhdr)))) {
 		rcode = -EINVAL;
 		goto cleanup;
···
 		rcode = -EINVAL;
 		goto cleanup;
 	}
-	actual_fibsize = sizeof(struct aac_srb) - sizeof(struct sgentry) +
+	actual_fibsize = sizeof(struct aac_srb) +
 		((user_srbcmd->sg.count & 0xff) * sizeof(struct sgentry));
 	actual_fibsize64 = actual_fibsize + (user_srbcmd->sg.count & 0xff) *
 	  (sizeof(struct sgentry64) - sizeof(struct sgentry));

drivers/scsi/aacraid/comminit.c

···
 	spin_lock_init(&dev->iq_lock);
 	dev->max_fib_size = sizeof(struct hw_fib);
 	dev->sg_tablesize = host->sg_tablesize = (dev->max_fib_size
-		- sizeof(struct aac_fibhdr)
-		- sizeof(struct aac_write) + sizeof(struct sgentry))
+		- sizeof(struct aac_fibhdr) - sizeof(struct aac_write))
 			/ sizeof(struct sgentry);
 	dev->comm_interface = AAC_COMM_PRODUCER;
 	dev->raw_io_interface = dev->raw_io_64 = 0;

drivers/scsi/aacraid/commsup.c

···
 	sg64->sg[0].addr[0] = cpu_to_le32((u32)(addr & 0xffffffff));
 	sg64->sg[0].count = cpu_to_le32(datasize);
 
-	ret = aac_fib_send(ScsiPortCommand64, fibptr, sizeof(struct aac_srb),
-				FsaNormal, 1, 1, NULL, NULL);
+	ret = aac_fib_send(ScsiPortCommand64, fibptr,
+			   sizeof(struct aac_srb) + sizeof(struct sgentry),
+			   FsaNormal, 1, 1, NULL, NULL);
 
 	dma_free_coherent(&dev->pdev->dev, datasize, dma_buf, addr);