From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932326AbWHaVfv (ORCPT ); Thu, 31 Aug 2006 17:35:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932196AbWHaVfv (ORCPT ); Thu, 31 Aug 2006 17:35:51 -0400 Received: from mx1.redhat.com ([66.187.233.31]:188 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S932338AbWHaVfu (ORCPT ); Thu, 31 Aug 2006 17:35:50 -0400 From: David Howells Subject: [PATCH 1/4] NOMMU: Implement /proc/pid/maps for NOMMU Date: Thu, 31 Aug 2006 22:35:30 +0100 To: torvalds@osdl.org, akpm@osdl.org Cc: linux-kernel@vger.kernel.org, uclinux-dev@uclinux.org, dhowells@redhat.com Message-Id: <20060831213530.29363.6372.stgit@warthog.cambridge.redhat.com> Content-Type: text/plain; charset=utf-8; format=fixed Content-Transfer-Encoding: 8bit User-Agent: StGIT/0.10 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: David Howells Implement /proc/pid/maps for NOMMU by reading the vm_area_list attached to current->mm->context.vmlist. Signed-Off-By: David Howells --- Documentation/nommu-mmap.txt | 3 ++ fs/proc/internal.h | 1 + fs/proc/nommu.c | 20 ++++++++--- fs/proc/task_nommu.c | 74 ++++++++++++++++++++++++++++++++++-------- include/linux/proc_fs.h | 2 + 5 files changed, 80 insertions(+), 20 deletions(-) diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt index b88ebe4..83f4b08 100644 --- a/Documentation/nommu-mmap.txt +++ b/Documentation/nommu-mmap.txt @@ -116,6 +116,9 @@ FURTHER NOTES ON NO-MMU MMAP (*) A list of all the mappings on the system is visible through /proc/maps in no-MMU mode. + (*) A list of all the mappings in use by a process is visible through + /proc//maps in no-MMU mode. + (*) Supplying MAP_FIXED or a requesting a particular mapping address will result in an error. diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 146a434..987c773 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -28,6 +28,7 @@ do { \ (vmi)->largest_chunk = 0; \ } while(0) +extern int nommu_vma_show(struct seq_file *, struct vm_area_struct *); #endif extern void create_seq_entry(char *name, mode_t mode, const struct file_operations *f); diff --git a/fs/proc/nommu.c b/fs/proc/nommu.c index cff10ab..d7dbdf9 100644 --- a/fs/proc/nommu.c +++ b/fs/proc/nommu.c @@ -33,19 +33,15 @@ #include #include "internal.h" /* - * display a list of all the VMAs the kernel knows about - * - nommu kernals have a single flat list + * display a single VMA to a sequenced file */ -static int nommu_vma_list_show(struct seq_file *m, void *v) +int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma) { - struct vm_area_struct *vma; unsigned long ino = 0; struct file *file; dev_t dev = 0; int flags, len; - vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb); - flags = vma->vm_flags; file = vma->vm_file; @@ -78,6 +74,18 @@ static int nommu_vma_list_show(struct se return 0; } +/* + * display a list of all the VMAs the kernel knows about + * - nommu kernals have a single flat list + */ +static int nommu_vma_list_show(struct seq_file *m, void *v) +{ + struct vm_area_struct *vma; + + vma = rb_entry((struct rb_node *) v, struct vm_area_struct, vm_rb); + return nommu_vma_show(m, vma); +} + static void *nommu_vma_list_start(struct seq_file *m, loff_t *_pos) { struct rb_node *_rb; diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c index 4616ed5..091aa8e 100644 --- a/fs/proc/task_nommu.c +++ b/fs/proc/task_nommu.c @@ -138,25 +138,63 @@ out: } /* - * Albert D. Cahalan suggested to fake entries for the traditional - * sections here. This might be worth investigating. + * display mapping lines for a particular process's /proc/pid/maps */ -static int show_map(struct seq_file *m, void *v) +static int show_map(struct seq_file *m, void *_vml) { - return 0; + struct vm_list_struct *vml = _vml; + return nommu_vma_show(m, vml->vma); } + static void *m_start(struct seq_file *m, loff_t *pos) { + struct proc_maps_private *priv = m->private; + struct vm_list_struct *vml; + struct mm_struct *mm; + loff_t n = *pos; + + /* pin the task and mm whilst we play with them */ + priv->task = get_pid_task(priv->pid, PIDTYPE_PID); + if (!priv->task) + return NULL; + + mm = get_task_mm(priv->task); + if (!mm) { + put_task_struct(priv->task); + priv->task = NULL; + return NULL; + } + + down_read(&mm->mmap_sem); + + /* start from the Nth VMA */ + for (vml = mm->context.vmlist; vml; vml = vml->next) + if (n-- == 0) + return vml; return NULL; } -static void m_stop(struct seq_file *m, void *v) + +static void m_stop(struct seq_file *m, void *_vml) { + struct proc_maps_private *priv = m->private; + + if (priv->task) { + struct mm_struct *mm = priv->task->mm; + up_read(&mm->mmap_sem); + mmput(mm); + put_task_struct(priv->task); + } } -static void *m_next(struct seq_file *m, void *v, loff_t *pos) + +static void *m_next(struct seq_file *m, void *_vml, loff_t *pos) { - return NULL; + struct vm_list_struct *vml = _vml; + + (*pos)++; + return vml ? vml->next : NULL; } -static struct seq_operations proc_pid_maps_op = { + +static struct seq_operations proc_pid_maps_ops = { .start = m_start, .next = m_next, .stop = m_stop, @@ -165,11 +203,19 @@ static struct seq_operations proc_pid_ma static int maps_open(struct inode *inode, struct file *file) { - int ret; - ret = seq_open(file, &proc_pid_maps_op); - if (!ret) { - struct seq_file *m = file->private_data; - m->private = NULL; + struct proc_maps_private *priv; + int ret = -ENOMEM; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (priv) { + priv->pid = proc_pid(inode); + ret = seq_open(file, &proc_pid_maps_ops); + if (!ret) { + struct seq_file *m = file->private_data; + m->private = priv; + } else { + kfree(priv); + } } return ret; } @@ -178,6 +224,6 @@ struct file_operations proc_maps_operati .open = maps_open, .read = seq_read, .llseek = seq_lseek, - .release = seq_release, + .release = seq_release_private, }; diff --git a/include/linux/proc_fs.h b/include/linux/proc_fs.h index 17e7578..73beb46 100644 --- a/include/linux/proc_fs.h +++ b/include/linux/proc_fs.h @@ -269,7 +269,9 @@ static inline struct proc_dir_entry *PDE struct proc_maps_private { struct pid *pid; struct task_struct *task; +#ifdef CONFIG_MMU struct vm_area_struct *tail_vma; +#endif }; #endif /* _LINUX_PROC_FS_H */