From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zeniv.linux.org.uk ([195.92.253.2]:43144 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030774AbeEZAEM (ORCPT ); Fri, 25 May 2018 20:04:12 -0400 From: Al Viro To: linux-fsdevel@vger.kernel.org Cc: Alexey Dobriyan Subject: [PATCH 4/5] procfs: switch instantiate_t to d_splice_alias() Date: Sat, 26 May 2018 01:04:09 +0100 Message-Id: <20180526000410.10804-4-viro@ZenIV.linux.org.uk> In-Reply-To: <20180526000410.10804-1-viro@ZenIV.linux.org.uk> References: <20180526000302.GK30522@ZenIV.linux.org.uk> <20180526000410.10804-1-viro@ZenIV.linux.org.uk> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: Al Viro ... and get rid of pointless struct inode *dir argument of those, while we are at it. Signed-off-by: Al Viro --- fs/proc/base.c | 93 ++++++++++++++++++++++++---------------------------- fs/proc/fd.c | 30 ++++++++--------- fs/proc/internal.h | 2 +- fs/proc/namespaces.c | 19 +++++------ 4 files changed, 65 insertions(+), 79 deletions(-) diff --git a/fs/proc/base.c b/fs/proc/base.c index 6e0875505898..de22c2002b38 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1878,8 +1878,8 @@ bool proc_fill_cache(struct file *file, struct dir_context *ctx, struct dentry *child, *dir = file->f_path.dentry; struct qstr qname = QSTR_INIT(name, len); struct inode *inode; - unsigned type; - ino_t ino; + unsigned type = DT_UNKNOWN; + ino_t ino = 1; child = d_hash_and_lookup(dir, &qname); if (!child) { @@ -1888,22 +1888,23 @@ bool proc_fill_cache(struct file *file, struct dir_context *ctx, if (IS_ERR(child)) goto end_instantiate; if (d_in_lookup(child)) { - int err = instantiate(d_inode(dir), child, task, ptr); + struct dentry *res; + res = instantiate(child, task, ptr); d_lookup_done(child); - if (err < 0) { - dput(child); + if (IS_ERR(res)) goto end_instantiate; + if (unlikely(res)) { + dput(child); + child = res; } } } inode = d_inode(child); ino = inode->i_ino; type = inode->i_mode >> 12; +end_instantiate: dput(child); return dir_emit(ctx, name, len, ino, type); - -end_instantiate: - return dir_emit(ctx, name, len, 1, DT_UNKNOWN); } /* @@ -2065,19 +2066,19 @@ static const struct inode_operations proc_map_files_link_inode_operations = { .setattr = proc_setattr, }; -static int -proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, +static struct dentry * +proc_map_files_instantiate(struct dentry *dentry, struct task_struct *task, const void *ptr) { fmode_t mode = (fmode_t)(unsigned long)ptr; struct proc_inode *ei; struct inode *inode; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | ((mode & FMODE_READ ) ? S_IRUSR : 0) | ((mode & FMODE_WRITE) ? S_IWUSR : 0)); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); ei = PROC_I(inode); ei->op.proc_get_link = map_files_get_link; @@ -2086,9 +2087,7 @@ proc_map_files_instantiate(struct inode *dir, struct dentry *dentry, inode->i_size = 64; d_set_d_op(dentry, &tid_map_files_dentry_operations); - d_add(dentry, inode); - - return 0; + return d_splice_alias(inode, dentry); } static struct dentry *proc_map_files_lookup(struct inode *dir, @@ -2097,19 +2096,19 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, unsigned long vm_start, vm_end; struct vm_area_struct *vma; struct task_struct *task; - int result; + struct dentry *result; struct mm_struct *mm; - result = -ENOENT; + result = ERR_PTR(-ENOENT); task = get_proc_task(dir); if (!task) goto out; - result = -EACCES; + result = ERR_PTR(-EACCES); if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) goto out_put_task; - result = -ENOENT; + result = ERR_PTR(-ENOENT); if (dname_to_vma_addr(dentry, &vm_start, &vm_end)) goto out_put_task; @@ -2123,7 +2122,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, goto out_no_vma; if (vma->vm_file) - result = proc_map_files_instantiate(dir, dentry, task, + result = proc_map_files_instantiate(dentry, task, (void *)(unsigned long)vma->vm_file->f_mode); out_no_vma: @@ -2132,7 +2131,7 @@ static struct dentry *proc_map_files_lookup(struct inode *dir, out_put_task: put_task_struct(task); out: - return ERR_PTR(result); + return result; } static const struct inode_operations proc_map_files_inode_operations = { @@ -2433,16 +2432,16 @@ static const struct file_operations proc_pid_set_timerslack_ns_operations = { .release = single_release, }; -static int proc_pident_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, const void *ptr) +static struct dentry *proc_pident_instantiate(struct dentry *dentry, + struct task_struct *task, const void *ptr) { const struct pid_entry *p = ptr; struct inode *inode; struct proc_inode *ei; - inode = proc_pid_make_inode(dir->i_sb, task, p->mode); + inode = proc_pid_make_inode(dentry->d_sb, task, p->mode); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); ei = PROC_I(inode); if (S_ISDIR(inode->i_mode)) @@ -2454,8 +2453,7 @@ static int proc_pident_instantiate(struct inode *dir, ei->op = p->op; pid_update_inode(task, inode); d_set_d_op(dentry, &pid_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } static struct dentry *proc_pident_lookup(struct inode *dir, @@ -2463,11 +2461,9 @@ static struct dentry *proc_pident_lookup(struct inode *dir, const struct pid_entry *ents, unsigned int nents) { - int error; struct task_struct *task = get_proc_task(dir); const struct pid_entry *p, *last; - - error = -ENOENT; + struct dentry *res = ERR_PTR(-ENOENT); if (!task) goto out_no_task; @@ -2486,11 +2482,11 @@ static struct dentry *proc_pident_lookup(struct inode *dir, if (p >= last) goto out; - error = proc_pident_instantiate(dir, dentry, task, p); + res = proc_pident_instantiate(dentry, task, p); out: put_task_struct(task); out_no_task: - return ERR_PTR(error); + return res; } static int proc_pident_readdir(struct file *file, struct dir_context *ctx, @@ -3133,15 +3129,14 @@ void proc_flush_task(struct task_struct *task) } } -static int proc_pid_instantiate(struct inode *dir, - struct dentry * dentry, +static struct dentry *proc_pid_instantiate(struct dentry * dentry, struct task_struct *task, const void *ptr) { struct inode *inode; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); inode->i_op = &proc_tgid_base_inode_operations; inode->i_fop = &proc_tgid_base_operations; @@ -3151,16 +3146,15 @@ static int proc_pid_instantiate(struct inode *dir, pid_update_inode(task, inode); d_set_d_op(dentry, &pid_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) { - int result = -ENOENT; struct task_struct *task; unsigned tgid; struct pid_namespace *ns; + struct dentry *result = ERR_PTR(-ENOENT); tgid = name_to_int(&dentry->d_name); if (tgid == ~0U) @@ -3175,10 +3169,10 @@ struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsign if (!task) goto out; - result = proc_pid_instantiate(dir, dentry, task, NULL); + result = proc_pid_instantiate(dentry, task, NULL); put_task_struct(task); out: - return ERR_PTR(result); + return result; } /* @@ -3426,13 +3420,13 @@ static const struct inode_operations proc_tid_base_inode_operations = { .setattr = proc_setattr, }; -static int proc_task_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, const void *ptr) +static struct dentry *proc_task_instantiate(struct dentry *dentry, + struct task_struct *task, const void *ptr) { struct inode *inode; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); inode->i_op = &proc_tid_base_inode_operations; inode->i_fop = &proc_tid_base_operations; @@ -3442,17 +3436,16 @@ static int proc_task_instantiate(struct inode *dir, pid_update_inode(task, inode); d_set_d_op(dentry, &pid_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags) { - int result = -ENOENT; struct task_struct *task; struct task_struct *leader = get_proc_task(dir); unsigned tid; struct pid_namespace *ns; + struct dentry *result = ERR_PTR(-ENOENT); if (!leader) goto out_no_task; @@ -3472,13 +3465,13 @@ static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry if (!same_thread_group(leader, task)) goto out_drop_task; - result = proc_task_instantiate(dir, dentry, task, NULL); + result = proc_task_instantiate(dentry, task, NULL); out_drop_task: put_task_struct(task); out: put_task_struct(leader); out_no_task: - return ERR_PTR(result); + return result; } /* diff --git a/fs/proc/fd.c b/fs/proc/fd.c index 694faeacf42f..e6a69fd6a2bb 100644 --- a/fs/proc/fd.c +++ b/fs/proc/fd.c @@ -179,17 +179,16 @@ struct fd_data { unsigned fd; }; -static int -proc_fd_instantiate(struct inode *dir, struct dentry *dentry, - struct task_struct *task, const void *ptr) +static struct dentry *proc_fd_instantiate(struct dentry *dentry, + struct task_struct *task, const void *ptr) { const struct fd_data *data = ptr; struct proc_inode *ei; struct inode *inode; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK); + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); ei = PROC_I(inode); ei->fd = data->fd; @@ -201,8 +200,7 @@ proc_fd_instantiate(struct inode *dir, struct dentry *dentry, tid_fd_update_inode(task, inode, data->mode); d_set_d_op(dentry, &tid_fd_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } static struct dentry *proc_lookupfd_common(struct inode *dir, @@ -210,8 +208,8 @@ static struct dentry *proc_lookupfd_common(struct inode *dir, instantiate_t instantiate) { struct task_struct *task = get_proc_task(dir); - int result = -ENOENT; struct fd_data data = {.fd = name_to_int(&dentry->d_name)}; + struct dentry *result = ERR_PTR(-ENOENT); if (!task) goto out_no_task; @@ -220,11 +218,11 @@ static struct dentry *proc_lookupfd_common(struct inode *dir, if (!tid_fd_mode(task, data.fd, &data.mode)) goto out; - result = instantiate(dir, dentry, task, &data); + result = instantiate(dentry, task, &data); out: put_task_struct(task); out_no_task: - return ERR_PTR(result); + return result; } static int proc_readfd_common(struct file *file, struct dir_context *ctx, @@ -320,17 +318,16 @@ const struct inode_operations proc_fd_inode_operations = { .setattr = proc_setattr, }; -static int -proc_fdinfo_instantiate(struct inode *dir, struct dentry *dentry, - struct task_struct *task, const void *ptr) +static struct dentry *proc_fdinfo_instantiate(struct dentry *dentry, + struct task_struct *task, const void *ptr) { const struct fd_data *data = ptr; struct proc_inode *ei; struct inode *inode; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFREG | S_IRUSR); + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFREG | S_IRUSR); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); ei = PROC_I(inode); ei->fd = data->fd; @@ -339,8 +336,7 @@ proc_fdinfo_instantiate(struct inode *dir, struct dentry *dentry, tid_fd_update_inode(task, inode, 0); d_set_d_op(dentry, &tid_fd_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } static struct dentry * diff --git a/fs/proc/internal.h b/fs/proc/internal.h index 04a455b9ae69..275b062e58af 100644 --- a/fs/proc/internal.h +++ b/fs/proc/internal.h @@ -154,7 +154,7 @@ extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned extern loff_t mem_lseek(struct file *, loff_t, int); /* Lookups */ -typedef int instantiate_t(struct inode *, struct dentry *, +typedef struct dentry *instantiate_t(struct dentry *, struct task_struct *, const void *); extern bool proc_fill_cache(struct file *, struct dir_context *, const char *, int, instantiate_t, struct task_struct *, const void *); diff --git a/fs/proc/namespaces.c b/fs/proc/namespaces.c index ad1adce6541d..dd2b35f78b09 100644 --- a/fs/proc/namespaces.c +++ b/fs/proc/namespaces.c @@ -87,16 +87,16 @@ static const struct inode_operations proc_ns_link_inode_operations = { .setattr = proc_setattr, }; -static int proc_ns_instantiate(struct inode *dir, - struct dentry *dentry, struct task_struct *task, const void *ptr) +static struct dentry *proc_ns_instantiate(struct dentry *dentry, + struct task_struct *task, const void *ptr) { const struct proc_ns_operations *ns_ops = ptr; struct inode *inode; struct proc_inode *ei; - inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK | S_IRWXUGO); + inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK | S_IRWXUGO); if (!inode) - return -ENOENT; + return ERR_PTR(-ENOENT); ei = PROC_I(inode); inode->i_op = &proc_ns_link_inode_operations; @@ -104,8 +104,7 @@ static int proc_ns_instantiate(struct inode *dir, pid_update_inode(task, inode); d_set_d_op(dentry, &pid_dentry_operations); - d_add(dentry, inode); - return 0; + return d_splice_alias(inode, dentry); } static int proc_ns_dir_readdir(struct file *file, struct dir_context *ctx) @@ -144,12 +143,10 @@ const struct file_operations proc_ns_dir_operations = { static struct dentry *proc_ns_dir_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { - int error; struct task_struct *task = get_proc_task(dir); const struct proc_ns_operations **entry, **last; unsigned int len = dentry->d_name.len; - - error = -ENOENT; + struct dentry *res = ERR_PTR(-ENOENT); if (!task) goto out_no_task; @@ -164,11 +161,11 @@ static struct dentry *proc_ns_dir_lookup(struct inode *dir, if (entry == last) goto out; - error = proc_ns_instantiate(dir, dentry, task, *entry); + res = proc_ns_instantiate(dentry, task, *entry); out: put_task_struct(task); out_no_task: - return ERR_PTR(error); + return res; } const struct inode_operations proc_ns_dir_inode_operations = { -- 2.11.0