Convert snd-page-alloc proc file to use seq_file

Use seq_file for the proc file read/write of snd-page-alloc module. This automatically fixes bugs in the old proc code. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Convert snd-page-alloc proc file to use seq_file
Use seq_file for the proc file read/write of snd-page-alloc module. This automatically fixes bugs in the old proc code. Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Takashi Iwai · Linus Torvalds
1 parent 7bae705ef2
Showing 1 changed file with 39 additions and 29 deletions Side-by-side Diff
sound/core/memalloc.c
@@ -27,6 +27,7 @@
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/mm.h>
+#include <linux/seq_file.h>
 #include <asm/uaccess.h>
 #include <linux/dma-mapping.h>
 #include <linux/moduleparam.h>
  
  
  
  
  
  
  
  
  
@@ -481,53 +482,54 @@
 #define SND_MEM_PROC_FILE	"driver/snd-page-alloc"
 static struct proc_dir_entry *snd_mem_proc;
  
-static int snd_mem_proc_read(char *page, char **start, off_t off,
-			     int count, int *eof, void *data)
+static int snd_mem_proc_read(struct seq_file *seq, void *offset)
 {
-	int len = 0;
 	long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
 	struct snd_mem_list *mem;
 	int devno;
 	static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG", "SBUS" };
  
 	mutex_lock(&list_mutex);
-	len += snprintf(page + len, count - len,
-			"pages  : %li bytes (%li pages per %likB)\n",
-			pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
+	seq_printf(seq, "pages  : %li bytes (%li pages per %likB)\n",
+		   pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
 	devno = 0;
 	list_for_each_entry(mem, &mem_list_head, list) {
 		devno++;
-		len += snprintf(page + len, count - len,
-				"buffer %d : ID %08x : type %s\n",
-				devno, mem->id, types[mem->buffer.dev.type]);
-		len += snprintf(page + len, count - len,
-				"  addr = 0x%lx, size = %d bytes\n",
-				(unsigned long)mem->buffer.addr, (int)mem->buffer.bytes);
+		seq_printf(seq, "buffer %d : ID %08x : type %s\n",
+			   devno, mem->id, types[mem->buffer.dev.type]);
+		seq_printf(seq, "  addr = 0x%lx, size = %d bytes\n",
+			   (unsigned long)mem->buffer.addr,
+			   (int)mem->buffer.bytes);
 	}
 	mutex_unlock(&list_mutex);
-	return len;
+	return 0;
 }
  
+static int snd_mem_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, snd_mem_proc_read, NULL);
+}
+
 /* FIXME: for pci only - other bus? */
 #ifdef CONFIG_PCI
 #define gettoken(bufp) strsep(bufp, " \t\n")
  
-static int snd_mem_proc_write(struct file *file, const char __user *buffer,
-			      unsigned long count, void *data)
+static ssize_t snd_mem_proc_write(struct file *file, const char __user * buffer,
+				  size_t count, loff_t * ppos)
 {
 	char buf[128];
 	char *token, *p;
  
-	if (count > ARRAY_SIZE(buf) - 1)
-		count = ARRAY_SIZE(buf) - 1;
+	if (count > sizeof(buf) - 1)
+		return -EINVAL;
 	if (copy_from_user(buf, buffer, count))
 		return -EFAULT;
-	buf[ARRAY_SIZE(buf) - 1] = '] = '\0';';
+	buf[count] = '] = '\0';';
  
 	p = buf;
 	token = gettoken(&p);
 	if (! token || *token == '#')
-		return (int)count;
+		return count;
 	if (strcmp(token, "add") == 0) {
 		char *endp;
 		int vendor, device, size, buffers;
@@ -548,7 +550,7 @@
 		    (buffers = simple_strtol(token, NULL, 0)) <= 0 ||
 		    buffers > 4) {
 			printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
-			return (int)count;
+			return count;
 		}
 		vendor &= 0xffff;
 		device &= 0xffff;
@@ -560,7 +562,7 @@
 				if (pci_set_dma_mask(pci, mask) < 0 ||
 				    pci_set_consistent_dma_mask(pci, mask) < 0) {
 					printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
-					return (int)count;
+					return count;
 				}
 			}
 			for (i = 0; i < buffers; i++) {
@@ -570,7 +572,7 @@
 							size, &dmab) < 0) {
 					printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
 					pci_dev_put(pci);
-					return (int)count;
+					return count;
 				}
 				snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
 			}
  
@@ -596,9 +598,21 @@
 		free_all_reserved_pages();
 	else
 		printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
-	return (int)count;
+	return count;
 }
 #endif /* CONFIG_PCI */
+
+static const struct file_operations snd_mem_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= snd_mem_proc_open,
+	.read		= seq_read,
+#ifdef CONFIG_PCI
+	.write		= snd_mem_proc_write,
+#endif
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
 #endif /* CONFIG_PROC_FS */
  
 /*
@@ -609,12 +623,8 @@
 {
 #ifdef CONFIG_PROC_FS
 	snd_mem_proc = create_proc_entry(SND_MEM_PROC_FILE, 0644, NULL);
-	if (snd_mem_proc) {
-		snd_mem_proc->read_proc = snd_mem_proc_read;
-#ifdef CONFIG_PCI
-		snd_mem_proc->write_proc = snd_mem_proc_write;
-#endif
-	}
+	if (snd_mem_proc)
+		snd_mem_proc->proc_fops = &snd_mem_proc_fops;
 #endif
 	return 0;
 }
...	...	@@ -27,6 +27,7 @@
27	27	#include <linux/pci.h>
28	28	#include <linux/slab.h>
29	29	#include <linux/mm.h>
	30	+#include <linux/seq_file.h>
30	31	#include <asm/uaccess.h>
31	32	#include <linux/dma-mapping.h>
32	33	#include <linux/moduleparam.h>
33	34
34	35
35	36
36	37
37	38
38	39
39	40
40	41
41	42
...	...	@@ -481,53 +482,54 @@
481	482	#define SND_MEM_PROC_FILE "driver/snd-page-alloc"
482	483	static struct proc_dir_entry *snd_mem_proc;
483	484
484		-static int snd_mem_proc_read(char page, char *start, off_t off,
485		- int count, int eof, void data)
	485	+static int snd_mem_proc_read(struct seq_file seq, void offset)
486	486	{
487		- int len = 0;
488	487	long pages = snd_allocated_pages >> (PAGE_SHIFT-12);
489	488	struct snd_mem_list *mem;
490	489	int devno;
491	490	static char *types[] = { "UNKNOWN", "CONT", "DEV", "DEV-SG", "SBUS" };
492	491
493	492	mutex_lock(&list_mutex);
494		- len += snprintf(page + len, count - len,
495		- "pages : %li bytes (%li pages per %likB)\n",
496		- pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
	493	+ seq_printf(seq, "pages : %li bytes (%li pages per %likB)\n",
	494	+ pages * PAGE_SIZE, pages, PAGE_SIZE / 1024);
497	495	devno = 0;
498	496	list_for_each_entry(mem, &mem_list_head, list) {
499	497	devno++;
500		- len += snprintf(page + len, count - len,
501		- "buffer %d : ID %08x : type %s\n",
502		- devno, mem->id, types[mem->buffer.dev.type]);
503		- len += snprintf(page + len, count - len,
504		- " addr = 0x%lx, size = %d bytes\n",
505		- (unsigned long)mem->buffer.addr, (int)mem->buffer.bytes);
	498	+ seq_printf(seq, "buffer %d : ID %08x : type %s\n",
	499	+ devno, mem->id, types[mem->buffer.dev.type]);
	500	+ seq_printf(seq, " addr = 0x%lx, size = %d bytes\n",
	501	+ (unsigned long)mem->buffer.addr,
	502	+ (int)mem->buffer.bytes);
506	503	}
507	504	mutex_unlock(&list_mutex);
508		- return len;
	505	+ return 0;
509	506	}
510	507
	508	+static int snd_mem_proc_open(struct inode inode, struct file file)
	509	+{
	510	+ return single_open(file, snd_mem_proc_read, NULL);
	511	+}
	512	+
511	513	/* FIXME: for pci only - other bus? */
512	514	#ifdef CONFIG_PCI
513	515	#define gettoken(bufp) strsep(bufp, " \t\n")
514	516
515		-static int snd_mem_proc_write(struct file file, const char __user buffer,
516		- unsigned long count, void *data)
	517	+static ssize_t snd_mem_proc_write(struct file file, const char __user buffer,
	518	+ size_t count, loff_t * ppos)
517	519	{
518	520	char buf[128];
519	521	char token, p;
520	522
521		- if (count > ARRAY_SIZE(buf) - 1)
522		- count = ARRAY_SIZE(buf) - 1;
	523	+ if (count > sizeof(buf) - 1)
	524	+ return -EINVAL;
523	525	if (copy_from_user(buf, buffer, count))
524	526	return -EFAULT;
525		- buf[ARRAY_SIZE(buf) - 1] = '] = '\0';';
	527	+ buf[count] = '] = '\0';';
526	528
527	529	p = buf;
528	530	token = gettoken(&p);
529	531	if (! token \|\| *token == '#')
530		- return (int)count;
	532	+ return count;
531	533	if (strcmp(token, "add") == 0) {
532	534	char *endp;
533	535	int vendor, device, size, buffers;
...	...	@@ -548,7 +550,7 @@
548	550	(buffers = simple_strtol(token, NULL, 0)) <= 0 \|\|
549	551	buffers > 4) {
550	552	printk(KERN_ERR "snd-page-alloc: invalid proc write format\n");
551		- return (int)count;
	553	+ return count;
552	554	}
553	555	vendor &= 0xffff;
554	556	device &= 0xffff;
...	...	@@ -560,7 +562,7 @@
560	562	if (pci_set_dma_mask(pci, mask) < 0 \|\|
561	563	pci_set_consistent_dma_mask(pci, mask) < 0) {
562	564	printk(KERN_ERR "snd-page-alloc: cannot set DMA mask %lx for pci %04x:%04x\n", mask, vendor, device);
563		- return (int)count;
	565	+ return count;
564	566	}
565	567	}
566	568	for (i = 0; i < buffers; i++) {
...	...	@@ -570,7 +572,7 @@
570	572	size, &dmab) < 0) {
571	573	printk(KERN_ERR "snd-page-alloc: cannot allocate buffer pages (size = %d)\n", size);
572	574	pci_dev_put(pci);
573		- return (int)count;
	575	+ return count;
574	576	}
575	577	snd_dma_reserve_buf(&dmab, snd_dma_pci_buf_id(pci));
576	578	}
577	579
...	...	@@ -596,9 +598,21 @@
596	598	free_all_reserved_pages();
597	599	else
598	600	printk(KERN_ERR "snd-page-alloc: invalid proc cmd\n");
599		- return (int)count;
	601	+ return count;
600	602	}
601	603	#endif /* CONFIG_PCI */
	604	+
	605	+static const struct file_operations snd_mem_proc_fops = {
	606	+ .owner = THIS_MODULE,
	607	+ .open = snd_mem_proc_open,
	608	+ .read = seq_read,
	609	+#ifdef CONFIG_PCI
	610	+ .write = snd_mem_proc_write,
	611	+#endif
	612	+ .llseek = seq_lseek,
	613	+ .release = single_release,
	614	+};
	615	+
602	616	#endif /* CONFIG_PROC_FS */
603	617
604	618	/*
...	...	@@ -609,12 +623,8 @@
609	623	{
610	624	#ifdef CONFIG_PROC_FS
611	625	snd_mem_proc = create_proc_entry(SND_MEM_PROC_FILE, 0644, NULL);
612		- if (snd_mem_proc) {
613		- snd_mem_proc->read_proc = snd_mem_proc_read;
614		-#ifdef CONFIG_PCI
615		- snd_mem_proc->write_proc = snd_mem_proc_write;
616		-#endif
617		- }
	626	+ if (snd_mem_proc)
	627	+ snd_mem_proc->proc_fops = &snd_mem_proc_fops;
618	628	#endif
619	629	return 0;
620	630	}