From f18e439d1035d059534d261c414af33f89aee89a Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 12 Aug 2008 15:09:03 -0700 Subject: [PATCH] genirq: switch /proc/irq/*/smp_affinity et al to seqfiles Switch /proc/irq/*/smp_affinity , /proc/irq/default_smp_affinity to seq_files. cat(1) reads with 1024 chunks by default, with high enough NR_CPUS, there will be -EINVAL. As side effect, there are now two less users of the ->read_proc interface. Signed-off-by: Alexey Dobriyan Cc: Paul Jackson Cc: Mike Travis Cc: Al Viro Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/irq/proc.c | 96 +++++++++++++++++++++++++---------------------- 1 file changed, 51 insertions(+), 45 deletions(-) diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 6c6d35d68ee..a09dd29c2fd 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -8,6 +8,7 @@ #include #include +#include #include #include "internals.h" @@ -16,23 +17,18 @@ static struct proc_dir_entry *root_irq_dir; #ifdef CONFIG_SMP -static int irq_affinity_read_proc(char *page, char **start, off_t off, - int count, int *eof, void *data) +static int irq_affinity_proc_show(struct seq_file *m, void *v) { - struct irq_desc *desc = irq_desc + (long)data; + struct irq_desc *desc = irq_desc + (long)m->private; cpumask_t *mask = &desc->affinity; - int len; #ifdef CONFIG_GENERIC_PENDING_IRQ if (desc->status & IRQ_MOVE_PENDING) mask = &desc->pending_mask; #endif - len = cpumask_scnprintf(page, count, *mask); - - if (count - len < 2) - return -EINVAL; - len += sprintf(page + len, "\n"); - return len; + seq_cpumask(m, mask); + seq_putc(m, '\n'); + return 0; } #ifndef is_affinity_mask_valid @@ -40,11 +36,12 @@ static int irq_affinity_read_proc(char *page, char **start, off_t off, #endif int no_irq_affinity; -static int irq_affinity_write_proc(struct file *file, const char __user *buffer, - unsigned long count, void *data) +static ssize_t irq_affinity_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *pos) { - unsigned int irq = (int)(long)data, full_count = count, err; + unsigned int irq = (int)(long)PDE(file->f_path.dentry->d_inode)->data; cpumask_t new_value; + int err; if (!irq_desc[irq].chip->set_affinity || no_irq_affinity || irq_balancing_disabled(irq)) @@ -65,28 +62,38 @@ static int irq_affinity_write_proc(struct file *file, const char __user *buffer, if (!cpus_intersects(new_value, cpu_online_map)) /* Special case for empty set - allow the architecture code to set default SMP affinity. */ - return irq_select_affinity(irq) ? -EINVAL : full_count; + return irq_select_affinity(irq) ? -EINVAL : count; irq_set_affinity(irq, new_value); - return full_count; + return count; } -static int default_affinity_read(char *page, char **start, off_t off, - int count, int *eof, void *data) +static int irq_affinity_proc_open(struct inode *inode, struct file *file) { - int len = cpumask_scnprintf(page, count, irq_default_affinity); - if (count - len < 2) - return -EINVAL; - len += sprintf(page + len, "\n"); - return len; + return single_open(file, irq_affinity_proc_show, PDE(inode)->data); } -static int default_affinity_write(struct file *file, const char __user *buffer, - unsigned long count, void *data) +static const struct file_operations irq_affinity_proc_fops = { + .open = irq_affinity_proc_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = irq_affinity_proc_write, +}; + +static int default_affinity_show(struct seq_file *m, void *v) +{ + seq_cpumask(m, &irq_default_affinity); + seq_putc(m, '\n'); + return 0; +} + +static ssize_t default_affinity_write(struct file *file, + const char __user *buffer, size_t count, loff_t *ppos) { - unsigned int full_count = count, err; cpumask_t new_value; + int err; err = cpumask_parse_user(buffer, count, new_value); if (err) @@ -105,8 +112,21 @@ static int default_affinity_write(struct file *file, const char __user *buffer, irq_default_affinity = new_value; - return full_count; + return count; } + +static int default_affinity_open(struct inode *inode, struct file *file) +{ + return single_open(file, default_affinity_show, NULL); +} + +static const struct file_operations default_affinity_proc_fops = { + .open = default_affinity_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, + .write = default_affinity_write, +}; #endif static int irq_spurious_read(char *page, char **start, off_t off, @@ -178,16 +198,9 @@ void register_irq_proc(unsigned int irq) irq_desc[irq].dir = proc_mkdir(name, root_irq_dir); #ifdef CONFIG_SMP - { - /* create /proc/irq//smp_affinity */ - entry = create_proc_entry("smp_affinity", 0600, irq_desc[irq].dir); - - if (entry) { - entry->data = (void *)(long)irq; - entry->read_proc = irq_affinity_read_proc; - entry->write_proc = irq_affinity_write_proc; - } - } + /* create /proc/irq//smp_affinity */ + proc_create_data("smp_affinity", 0600, irq_desc[irq].dir, + &irq_affinity_proc_fops, (void *)(long)irq); #endif entry = create_proc_entry("spurious", 0444, irq_desc[irq].dir); @@ -208,15 +221,8 @@ void unregister_handler_proc(unsigned int irq, struct irqaction *action) void register_default_affinity_proc(void) { #ifdef CONFIG_SMP - struct proc_dir_entry *entry; - - /* create /proc/irq/default_smp_affinity */ - entry = create_proc_entry("default_smp_affinity", 0600, root_irq_dir); - if (entry) { - entry->data = NULL; - entry->read_proc = default_affinity_read; - entry->write_proc = default_affinity_write; - } + proc_create("irq/default_smp_affinity", 0600, NULL, + &default_affinity_proc_fops); #endif } -- 2.41.1