From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: jeffm@suse.com To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Al Viro , "Eric W . Biederman" , Alexey Dobriyan , Oleg Nesterov , Jeff Mahoney Subject: [PATCH 1/5] procfs: factor out a few helpers Date: Mon, 23 Apr 2018 22:21:02 -0400 Message-Id: <20180424022106.16952-2-jeffm@suse.com> In-Reply-To: <20180424022106.16952-1-jeffm@suse.com> References: <20180424022106.16952-1-jeffm@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: From: Jeff Mahoney In order to make the following series easier to review, this patch factors out a few helpers: - proc_fill_cache_entry: proc_fill_cache that takes an entry instead of an entry, a name, and a name length - pident_lookup_task: proc_pident_lookup that takes a task, allowing the caller to do the task validation - pid_entry_match_dentry: the comparison between a dentry's name and a pid_entry Signed-off-by: Jeff Mahoney --- fs/proc/base.c | 60 ++++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 40 insertions(+), 20 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 9298324325ed..e9876a89a5ad 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -2453,19 +2453,28 @@ static int proc_pident_instantiate(struct inode *dir, return -ENOENT; } -static struct dentry *proc_pident_lookup(struct inode *dir, - struct dentry *dentry, - const struct pid_entry *ents, - unsigned int nents) +static bool proc_fill_cache_entry(struct file *file, struct dir_context *ctx, + const struct pid_entry *entry, + struct task_struct *task) { - int error; - struct task_struct *task = get_proc_task(dir); - const struct pid_entry *p, *last; + return proc_fill_cache(file, ctx, entry->name, entry->len, + proc_pident_instantiate, task, entry); +} - error = -ENOENT; +static bool pid_entry_match_dentry(const struct pid_entry *entry, + const struct dentry *dentry) +{ + if (entry->len != dentry->d_name.len) + return false; + return !memcmp(dentry->d_name.name, entry->name, entry->len); +} - if (!task) - goto out_no_task; +static int proc_pident_lookup_task(struct inode *dir, struct dentry *dentry, + const struct pid_entry *ents, + unsigned int nents, + struct task_struct *task) +{ + const struct pid_entry *p, *last; /* * Yes, it does not scale. And it should not. Don't add @@ -2473,18 +2482,30 @@ static struct dentry *proc_pident_lookup(struct inode *dir, */ last = &ents[nents]; for (p = ents; p < last; p++) { - if (p->len != dentry->d_name.len) - continue; - if (!memcmp(dentry->d_name.name, p->name, p->len)) + if (pid_entry_match_dentry(p, dentry)) break; } if (p >= last) - goto out; + return -ENOENT; + + return proc_pident_instantiate(dir, dentry, task, p); +} + +static struct dentry *proc_pident_lookup(struct inode *dir, + struct dentry *dentry, + const struct pid_entry *ents, + unsigned int nents) +{ + struct task_struct *task; + int error = -ENOENT; + + task = get_proc_task(dir); + if (task) { + error = proc_pident_lookup_task(dir, dentry, ents, + nents, task); + put_task_struct(task); + } - error = proc_pident_instantiate(dir, dentry, task, p); -out: - put_task_struct(task); -out_no_task: return ERR_PTR(error); } @@ -2504,8 +2525,7 @@ static int proc_pident_readdir(struct file *file, struct dir_context *ctx, goto out; for (p = ents + (ctx->pos - 2); p < ents + nents; p++) { - if (!proc_fill_cache(file, ctx, p->name, p->len, - proc_pident_instantiate, task, p)) + if (!proc_fill_cache_entry(file, ctx, p, task)) break; ctx->pos++; } -- 2.12.3