procfs: switch instantiate_t to d_splice_alias()

... and get rid of pointless struct inode *dir argument of those,
while we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2018-05-03 09:21:05 -04:00
parent 9883638641
commit 0168b9e38c
4 changed files with 65 additions and 79 deletions

View File

@ -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 @@ out_no_vma:
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;
}
/*

View File

@ -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 *

View File

@ -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 *);

View File

@ -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 = {