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078cd8279e
CURRENT_TIME macro is not appropriate for filesystems as it doesn't use the right granularity for filesystem timestamps. Use current_time() instead. CURRENT_TIME is also not y2038 safe. This is also in preparation for the patch that transitions vfs timestamps to use 64 bit time and hence make them y2038 safe. As part of the effort current_time() will be extended to do range checks. Hence, it is necessary for all file system timestamps to use current_time(). Also, current_time() will be transitioned along with vfs to be y2038 safe. Note that whenever a single call to current_time() is used to change timestamps in different inodes, it is because they share the same time granularity. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Felipe Balbi <balbi@kernel.org> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Acked-by: David Sterba <dsterba@suse.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
86 lines
2.3 KiB
C
86 lines
2.3 KiB
C
#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/pid_namespace.h>
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#include "internal.h"
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/*
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* /proc/thread_self:
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*/
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static int proc_thread_self_readlink(struct dentry *dentry, char __user *buffer,
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int buflen)
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{
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struct pid_namespace *ns = dentry->d_sb->s_fs_info;
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pid_t tgid = task_tgid_nr_ns(current, ns);
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pid_t pid = task_pid_nr_ns(current, ns);
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char tmp[PROC_NUMBUF + 6 + PROC_NUMBUF];
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if (!pid)
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return -ENOENT;
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sprintf(tmp, "%d/task/%d", tgid, pid);
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return readlink_copy(buffer, buflen, tmp);
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}
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static const char *proc_thread_self_get_link(struct dentry *dentry,
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struct inode *inode,
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struct delayed_call *done)
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{
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struct pid_namespace *ns = inode->i_sb->s_fs_info;
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pid_t tgid = task_tgid_nr_ns(current, ns);
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pid_t pid = task_pid_nr_ns(current, ns);
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char *name;
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if (!pid)
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return ERR_PTR(-ENOENT);
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name = kmalloc(PROC_NUMBUF + 6 + PROC_NUMBUF,
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dentry ? GFP_KERNEL : GFP_ATOMIC);
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if (unlikely(!name))
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return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD);
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sprintf(name, "%d/task/%d", tgid, pid);
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set_delayed_call(done, kfree_link, name);
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return name;
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}
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static const struct inode_operations proc_thread_self_inode_operations = {
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.readlink = proc_thread_self_readlink,
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.get_link = proc_thread_self_get_link,
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};
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static unsigned thread_self_inum;
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int proc_setup_thread_self(struct super_block *s)
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{
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struct inode *root_inode = d_inode(s->s_root);
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struct pid_namespace *ns = s->s_fs_info;
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struct dentry *thread_self;
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inode_lock(root_inode);
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thread_self = d_alloc_name(s->s_root, "thread-self");
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if (thread_self) {
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struct inode *inode = new_inode_pseudo(s);
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if (inode) {
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inode->i_ino = thread_self_inum;
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inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
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inode->i_mode = S_IFLNK | S_IRWXUGO;
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inode->i_uid = GLOBAL_ROOT_UID;
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inode->i_gid = GLOBAL_ROOT_GID;
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inode->i_op = &proc_thread_self_inode_operations;
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d_add(thread_self, inode);
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} else {
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dput(thread_self);
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thread_self = ERR_PTR(-ENOMEM);
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}
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} else {
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thread_self = ERR_PTR(-ENOMEM);
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}
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inode_unlock(root_inode);
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if (IS_ERR(thread_self)) {
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pr_err("proc_fill_super: can't allocate /proc/thread_self\n");
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return PTR_ERR(thread_self);
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}
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ns->proc_thread_self = thread_self;
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return 0;
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}
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void __init proc_thread_self_init(void)
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{
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proc_alloc_inum(&thread_self_inum);
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}
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