s390/cio,idal: code cleanup

Adjust coding style, partially refactor code, and use kcalloc()
instead of kmalloc() to allocate an idaw array.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

1 files changed, 64 insertions, 70 deletions

diff --git a/arch/s390/include/asm/idals.h b/arch/s390/include/asm/idals.h
index 59fcc3c72edfc..4621097775476 100644
--- a/arch/s390/include/asm/idals.h
+++ b/arch/s390/include/asm/idals.h
@@ -1,5 +1,5 @@
 /* SPDX-License-Identifier: GPL-2.0 */
-/* 
+/*
  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
  * Bugreports.to..: <Linux390@de.ibm.com>
@@ -17,32 +17,34 @@
 #include <linux/err.h>
 #include <linux/types.h>
 #include <linux/slab.h>
-#include <asm/cio.h>
 #include <linux/uaccess.h>
+#include <asm/cio.h>
 
-#define IDA_SIZE_LOG 12 /* 11 for 2k , 12 for 4k */
-#define IDA_BLOCK_SIZE (1L<<IDA_SIZE_LOG)
+#define IDA_SIZE_SHIFT		12
+#define IDA_BLOCK_SIZE		(1UL << IDA_SIZE_SHIFT)
 
-#define IDA_2K_SIZE_LOG 11
-#define IDA_2K_BLOCK_SIZE (1L << IDA_2K_SIZE_LOG)
+#define IDA_2K_SIZE_SHIFT	11
+#define IDA_2K_BLOCK_SIZE	(1UL << IDA_2K_SIZE_SHIFT)
 
 /*
  * Test if an address/length pair needs an idal list.
  */
-static inline int
-idal_is_needed(void *vaddr, unsigned int length)
+static inline bool idal_is_needed(void *vaddr, unsigned int length)
 {
 	return ((__pa(vaddr) + length - 1) >> 31) != 0;
 }
 
-
 /*
  * Return the number of idal words needed for an address/length pair.
  */
 static inline unsigned int idal_nr_words(void *vaddr, unsigned int length)
 {
-	return ((__pa(vaddr) & (IDA_BLOCK_SIZE-1)) + length +
-		(IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
+	unsigned int cidaw;
+
+	cidaw = __pa(vaddr) & (IDA_BLOCK_SIZE - 1);
+	cidaw += length + IDA_BLOCK_SIZE - 1;
+	cidaw >>= IDA_SIZE_SHIFT;
+	return cidaw;
 }
 
 /*
@@ -50,23 +52,24 @@ static inline unsigned int idal_nr_words(void *vaddr, unsigned int length)
  */
 static inline unsigned int idal_2k_nr_words(void *vaddr, unsigned int length)
 {
-	return ((__pa(vaddr) & (IDA_2K_BLOCK_SIZE - 1)) + length +
-		(IDA_2K_BLOCK_SIZE - 1)) >> IDA_2K_SIZE_LOG;
+	unsigned int cidaw;
+
+	cidaw = __pa(vaddr) & (IDA_2K_BLOCK_SIZE - 1);
+	cidaw += length + IDA_2K_BLOCK_SIZE - 1;
+	cidaw >>= IDA_2K_SIZE_SHIFT;
+	return cidaw;
 }
 
 /*
  * Create the list of idal words for an address/length pair.
  */
-static inline unsigned long *idal_create_words(unsigned long *idaws,
-					       void *vaddr, unsigned int length)
+static inline unsigned long *idal_create_words(unsigned long *idaws, void *vaddr, unsigned int length)
 {
-	unsigned long paddr;
+	unsigned long paddr = __pa(vaddr);
 	unsigned int cidaw;
 
-	paddr = __pa(vaddr);
-	cidaw = ((paddr & (IDA_BLOCK_SIZE-1)) + length + 
-		 (IDA_BLOCK_SIZE-1)) >> IDA_SIZE_LOG;
 	*idaws++ = paddr;
+	cidaw = idal_nr_words(vaddr, length);
 	paddr &= -IDA_BLOCK_SIZE;
 	while (--cidaw > 0) {
 		paddr += IDA_BLOCK_SIZE;
@@ -79,8 +82,7 @@ static inline unsigned long *idal_create_words(unsigned long *idaws,
  * Sets the address of the data in CCW.
  * If necessary it allocates an IDAL and sets the appropriate flags.
  */
-static inline int
-set_normalized_cda(struct ccw1 * ccw, void *vaddr)
+static inline int set_normalized_cda(struct ccw1 *ccw, void *vaddr)
 {
 	unsigned int nridaws;
 	unsigned long *idal;
@@ -89,26 +91,24 @@ set_normalized_cda(struct ccw1 * ccw, void *vaddr)
 		return -EINVAL;
 	nridaws = idal_nr_words(vaddr, ccw->count);
 	if (nridaws > 0) {
-		idal = kmalloc(nridaws * sizeof(unsigned long),
-			       GFP_ATOMIC | GFP_DMA );
-		if (idal == NULL)
+		idal = kcalloc(nridaws, sizeof(*idal), GFP_ATOMIC | GFP_DMA);
+		if (!idal)
 			return -ENOMEM;
 		idal_create_words(idal, vaddr, ccw->count);
 		ccw->flags |= CCW_FLAG_IDA;
 		vaddr = idal;
 	}
-	ccw->cda = (__u32)(unsigned long) vaddr;
+	ccw->cda = (__u32)(unsigned long)vaddr;
 	return 0;
 }
 
 /*
  * Releases any allocated IDAL related to the CCW.
  */
-static inline void
-clear_normalized_cda(struct ccw1 * ccw)
+static inline void clear_normalized_cda(struct ccw1 *ccw)
 {
 	if (ccw->flags & CCW_FLAG_IDA) {
-		kfree((void *)(unsigned long) ccw->cda);
+		kfree((void *)(unsigned long)ccw->cda);
 		ccw->flags &= ~CCW_FLAG_IDA;
 	}
 	ccw->cda = 0;
@@ -126,86 +126,81 @@ struct idal_buffer {
 /*
  * Allocate an idal buffer
  */
-static inline struct idal_buffer *
-idal_buffer_alloc(size_t size, int page_order)
+static inline struct idal_buffer *idal_buffer_alloc(size_t size, int page_order)
 {
-	struct idal_buffer *ib;
 	int nr_chunks, nr_ptrs, i;
+	struct idal_buffer *ib;
 
-	nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
-	nr_chunks = (4096 << page_order) >> IDA_SIZE_LOG;
+	nr_ptrs = (size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_SHIFT;
+	nr_chunks = (PAGE_SIZE << page_order) >> IDA_SIZE_SHIFT;
 	ib = kmalloc(struct_size(ib, data, nr_ptrs), GFP_DMA | GFP_KERNEL);
-	if (ib == NULL)
+	if (!ib)
 		return ERR_PTR(-ENOMEM);
 	ib->size = size;
 	ib->page_order = page_order;
 	for (i = 0; i < nr_ptrs; i++) {
-		if ((i & (nr_chunks - 1)) != 0) {
-			ib->data[i] = ib->data[i-1] + IDA_BLOCK_SIZE;
-			continue;
-		}
-		ib->data[i] = (void *)
-			__get_free_pages(GFP_KERNEL, page_order);
-		if (ib->data[i] != NULL)
+		if (i & (nr_chunks - 1)) {
+			ib->data[i] = ib->data[i - 1] + IDA_BLOCK_SIZE;
 			continue;
-		// Not enough memory
-		while (i >= nr_chunks) {
-			i -= nr_chunks;
-			free_pages((unsigned long) ib->data[i],
-				   ib->page_order);
 		}
-		kfree(ib);
-		return ERR_PTR(-ENOMEM);
+		ib->data[i] = (void *)__get_free_pages(GFP_KERNEL, page_order);
+		if (!ib->data[i])
+			goto error;
 	}
 	return ib;
+error:
+	while (i >= nr_chunks) {
+		i -= nr_chunks;
+		free_pages((unsigned long)ib->data[i], ib->page_order);
+	}
+	kfree(ib);
+	return ERR_PTR(-ENOMEM);
 }
 
 /*
  * Free an idal buffer.
  */
-static inline void
-idal_buffer_free(struct idal_buffer *ib)
+static inline void idal_buffer_free(struct idal_buffer *ib)
 {
 	int nr_chunks, nr_ptrs, i;
 
-	nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_LOG;
-	nr_chunks = (4096 << ib->page_order) >> IDA_SIZE_LOG;
+	nr_ptrs = (ib->size + IDA_BLOCK_SIZE - 1) >> IDA_SIZE_SHIFT;
+	nr_chunks = (PAGE_SIZE << ib->page_order) >> IDA_SIZE_SHIFT;
 	for (i = 0; i < nr_ptrs; i += nr_chunks)
-		free_pages((unsigned long) ib->data[i], ib->page_order);
+		free_pages((unsigned long)ib->data[i], ib->page_order);
 	kfree(ib);
 }
 
 /*
  * Test if a idal list is really needed.
  */
-static inline int
-__idal_buffer_is_needed(struct idal_buffer *ib)
+static inline bool __idal_buffer_is_needed(struct idal_buffer *ib)
 {
-	return ib->size > (4096ul << ib->page_order) ||
-		idal_is_needed(ib->data[0], ib->size);
+	if (ib->size > (PAGE_SIZE << ib->page_order))
+		return true;
+	return idal_is_needed(ib->data[0], ib->size);
 }
 
 /*
  * Set channel data address to idal buffer.
  */
-static inline void
-idal_buffer_set_cda(struct idal_buffer *ib, struct ccw1 *ccw)
+static inline void idal_buffer_set_cda(struct idal_buffer *ib, struct ccw1 *ccw)
 {
 	if (__idal_buffer_is_needed(ib)) {
-		// setup idals;
-		ccw->cda = (u32)(addr_t) ib->data;
+		/* Setup idals */
+		ccw->cda = (u32)(addr_t)ib->data;
 		ccw->flags |= CCW_FLAG_IDA;
-	} else
-		// we do not need idals - use direct addressing
-		ccw->cda = (u32)(addr_t) ib->data[0];
+	} else {
+		/* No idals needed - use direct addressing. */
+		ccw->cda = (u32)(addr_t)ib->data[0];
+	}
 	ccw->count = ib->size;
 }
 
 /*
  * Copy count bytes from an idal buffer to user memory
  */
-static inline size_t
-idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count)
+static inline size_t idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count)
 {
 	size_t left;
 	int i;
@@ -215,7 +210,7 @@ idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count)
 		left = copy_to_user(to, ib->data[i], IDA_BLOCK_SIZE);
 		if (left)
 			return left + count - IDA_BLOCK_SIZE;
-		to = (void __user *) to + IDA_BLOCK_SIZE;
+		to = (void __user *)to + IDA_BLOCK_SIZE;
 		count -= IDA_BLOCK_SIZE;
 	}
 	return copy_to_user(to, ib->data[i], count);
@@ -224,8 +219,7 @@ idal_buffer_to_user(struct idal_buffer *ib, void __user *to, size_t count)
 /*
  * Copy count bytes from user memory to an idal buffer
  */
-static inline size_t
-idal_buffer_from_user(struct idal_buffer *ib, const void __user *from, size_t count)
+static inline size_t idal_buffer_from_user(struct idal_buffer *ib, const void __user *from, size_t count)
 {
 	size_t left;
 	int i;
@@ -235,7 +229,7 @@ idal_buffer_from_user(struct idal_buffer *ib, const void __user *from, size_t co
 		left = copy_from_user(ib->data[i], from, IDA_BLOCK_SIZE);
 		if (left)
 			return left + count - IDA_BLOCK_SIZE;
-		from = (void __user *) from + IDA_BLOCK_SIZE;
+		from = (void __user *)from + IDA_BLOCK_SIZE;
 		count -= IDA_BLOCK_SIZE;
 	}
 	return copy_from_user(ib->data[i], from, count);