proc: Add CONFIG_PROC_FS_MIN

Add an option for a minimal proc, basically what's needed for a bootable and functionally useful system. This means /proc/mounts and /proc/filesystems at minimum, /proc/modules for a system with modules enabled. Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
tzanussi · Apr 24, 2014 · 6837943 · 6837943
1 parent 4bad1d8
commit 6837943
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Showing 20 changed files with 43 additions and 22 deletions.
diff --git a/block/genhd.c b/block/genhd.c
@@ -252,7 +252,7 @@ static inline int major_to_index(unsigned major)
 	return major % BLKDEV_MAJOR_HASH_SIZE;
 }
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 void blkdev_show(struct seq_file *seqf, off_t offset)
 {
 	struct blk_major_name *dp;
@@ -264,7 +264,7 @@ void blkdev_show(struct seq_file *seqf, off_t offset)
 		mutex_unlock(&block_class_lock);
 	}
 }
-#endif /* CONFIG_PROC_FS */
+#endif /* CONFIG_PROC_FS_MIN */
 
 /**
  * register_blkdev - register a new block device

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
@@ -1187,7 +1187,9 @@ static int __init init_mtd(void)
 	if (ret)
 		goto err_bdi3;
 
+#ifdef CONFIG_PROC_FS
 	proc_mtd = proc_create("mtd", 0, NULL, &mtd_proc_ops);
+#endif
 
 	ret = init_mtdchar();
 	if (ret)
@@ -1196,8 +1198,10 @@ static int __init init_mtd(void)
 	return 0;
 
 out_procfs:
+#ifdef CONFIG_PROC_FS
 	if (proc_mtd)
 		remove_proc_entry("mtd", NULL);
+#endif
 err_bdi3:
 	bdi_destroy(&mtd_bdi_ro_mappable);
 err_bdi2:

diff --git a/fs/Makefile b/fs/Makefile
@@ -19,7 +19,7 @@ else
 obj-y +=	no-block.o
 endif
 
-obj-$(CONFIG_PROC_FS) += proc_namespace.o
+obj-$(CONFIG_PROC_FS_MIN) += proc_namespace.o
 
 obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o
 obj-y				+= notify/
@@ -51,7 +51,7 @@ obj-$(CONFIG_FHANDLE)		+= fhandle.o
 
 obj-y				+= quota/
 
-obj-$(CONFIG_PROC_FS)		+= proc/
+obj-$(CONFIG_PROC_FS_MIN)	+= proc/
 obj-$(CONFIG_SYSFS)		+= sysfs/ kernfs/
 obj-$(CONFIG_CONFIGFS_FS)	+= configfs/
 obj-y				+= devpts/

diff --git a/fs/char_dev.c b/fs/char_dev.c
@@ -64,7 +64,7 @@ static inline int major_to_index(unsigned major)
 	return major % CHRDEV_MAJOR_HASH_SIZE;
 }
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 
 void chrdev_show(struct seq_file *f, off_t offset)
 {
@@ -78,7 +78,7 @@ void chrdev_show(struct seq_file *f, off_t offset)
 	}
 }
 
-#endif /* CONFIG_PROC_FS */
+#endif /* CONFIG_PROC_FS_MIN */
 
 /*
  * Register a single major with a specified minor range.

diff --git a/fs/filesystems.c b/fs/filesystems.c
@@ -217,7 +217,7 @@ int __init get_filesystem_list(char *buf)
 	return len;
 }
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 static int filesystems_proc_show(struct seq_file *m, void *v)
 {
 	struct file_system_type * tmp;

diff --git a/fs/namespace.c b/fs/namespace.c
@@ -1094,7 +1094,7 @@ void replace_mount_options(struct super_block *sb, char *options)
 }
 EXPORT_SYMBOL(replace_mount_options);
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 /* iterator; we want it to have access to namespace_sem, thus here... */
 static void *m_start(struct seq_file *m, loff_t *pos)
 {
@@ -1129,7 +1129,7 @@ const struct seq_operations mounts_op = {
 	.stop	= m_stop,
 	.show	= m_show,
 };
-#endif  /* CONFIG_PROC_FS */
+#endif  /* CONFIG_PROC_FS_MIN */
 
 /**
  * may_umount_tree - check if a mount tree is busy

diff --git a/fs/proc/Kconfig b/fs/proc/Kconfig
@@ -1,5 +1,6 @@
 config PROC_FS
 	bool "/proc file system support" if EXPERT
+	select PROC_FS_MIN
 	default y
 	help
 	  This is a virtual file system providing information about the status
@@ -28,6 +29,18 @@ config PROC_FS
 	  This option will enlarge your kernel by about 67 KB. Several
 	  programs depend on this, so everyone should say Y here.
 
+config PROC_FS_MIN
+	bool "minimal /proc file system support" if EXPERT
+	default n
+	help
+	  This is a minimal subset of proc, basically what's needed to
+	  boot.
+
+	  This option will enlarge your kernel by about 60 KB, in
+	  comparison to full PROC_FS of 170 KB.  PROC_FS selects this,
+	  so unless you know what you're doing, you can safely ignore
+	  this.
+
 config PROC_KCORE
 	bool "/proc/kcore support" if !ARM
 	depends on PROC_FS && MMU

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
@@ -599,7 +599,7 @@ extern int probe_irq_off(unsigned long);	/* returns 0 or negative on failure */
 extern unsigned int probe_irq_mask(unsigned long);	/* returns mask of ISA interrupts */
 #endif
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 /* Initialize /proc/irq/ */
 extern void init_irq_proc(void);
 #else

diff --git a/include/linux/irqdesc.h b/include/linux/irqdesc.h
@@ -64,7 +64,7 @@ struct irq_desc {
 	unsigned long		threads_oneshot;
 	atomic_t		threads_active;
 	wait_queue_head_t       wait_for_threads;
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 	struct proc_dir_entry	*dir;
 #endif
 	int			parent_irq;

diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h
@@ -30,7 +30,7 @@ struct pid_namespace {
 	struct kmem_cache *pid_cachep;
 	unsigned int level;
 	struct pid_namespace *parent;
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 	struct vfsmount *proc_mnt;
 	struct dentry *proc_self;
 #endif

diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h
@@ -9,7 +9,7 @@
 
 struct proc_dir_entry;
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 
 extern void proc_root_init(void);
 extern void proc_flush_task(struct task_struct *);

diff --git a/include/linux/proc_ns.h b/include/linux/proc_ns.h
@@ -39,7 +39,7 @@ enum {
 	PROC_PID_INIT_INO	= 0xEFFFFFFCU,
 };
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 
 extern int pid_ns_prepare_proc(struct pid_namespace *ns);
 extern void pid_ns_release_proc(struct pid_namespace *ns);
@@ -49,7 +49,7 @@ extern int proc_alloc_inum(unsigned int *pino);
 extern void proc_free_inum(unsigned int inum);
 extern bool proc_ns_inode(struct inode *inode);
 
-#else /* CONFIG_PROC_FS */
+#else /* CONFIG_PROC_FS_MIN */
 
 static inline int pid_ns_prepare_proc(struct pid_namespace *ns) { return 0; }
 static inline void pid_ns_release_proc(struct pid_namespace *ns) {}

diff --git a/include/linux/tty.h b/include/linux/tty.h
@@ -688,7 +688,7 @@ static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
 			schedule();					\
 			tty_lock(tty))
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 extern void proc_tty_register_driver(struct tty_driver *);
 extern void proc_tty_unregister_driver(struct tty_driver *);
 #else

diff --git a/init/Kconfig b/init/Kconfig
@@ -1745,7 +1745,7 @@ config HAVE_GENERIC_DMA_COHERENT
 
 config SLABINFO
 	bool
-	depends on PROC_FS
+	depends on PROC_FS_MIN
 	depends on SLAB || SLUB_DEBUG
 	default y
 

diff --git a/init/main.c b/init/main.c
@@ -629,7 +629,7 @@ asmlinkage void __init start_kernel(void)
 	signals_init();
 	/* rootfs populating might need page-writeback */
 	page_writeback_init();
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 	proc_root_init();
 #endif
 	cgroup_init();

diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
@@ -3,6 +3,6 @@ obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devr
 obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o
 obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
 obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o
-obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_PROC_FS_MIN) += proc.o
 obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
 obj-$(CONFIG_PM_SLEEP) += pm.o
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
@@ -83,7 +83,7 @@ irqreturn_t handle_irq_event(struct irq_desc *desc);
 void check_irq_resend(struct irq_desc *desc, unsigned int irq);
 bool irq_wait_for_poll(struct irq_desc *desc);
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 extern void register_irq_proc(unsigned int irq, struct irq_desc *desc);
 extern void unregister_irq_proc(unsigned int irq, struct irq_desc *desc);
 extern void register_handler_proc(unsigned int irq, struct irqaction *action);

diff --git a/kernel/module.c b/kernel/module.c
@@ -3617,7 +3617,7 @@ static char *module_flags(struct module *mod, char *buf)
 	return buf;
 }
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 /* Called by the /proc file system to return a list of modules. */
 static void *m_start(struct seq_file *m, loff_t *pos)
 {

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
@@ -2522,7 +2522,7 @@ void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms)
 }
 #endif	/* CONFIG_SMP */
 
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_PROC_FS_MIN
 static void *s_start(struct seq_file *m, loff_t *pos)
 	__acquires(&vmap_area_lock)
 {

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
@@ -4110,15 +4110,19 @@ static int __net_init packet_net_init(struct net *net)
 	mutex_init(&net->packet.sklist_lock);
 	INIT_HLIST_HEAD(&net->packet.sklist);
 
+#ifdef CONFIG_PROC_FS
 	if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
 		return -ENOMEM;
+#endif
 
 	return 0;
 }
 
 static void __net_exit packet_net_exit(struct net *net)
 {
+#ifdef CONFIG_PROC_FS
 	remove_proc_entry("packet", net->proc_net);
+#endif
 }
 
 static struct pernet_operations packet_net_ops = {