[PATCH 2/4] Replace pid_t in autofs with struct pid reference
From: Sukadev Bhattiprolu <sukadev@us.ibm.com> Subject: [PATCH 2/4] Replace pid_t in autofs with struct pid reference. Make autofs container-friendly by caching struct pid reference rather than pid_t and using pid_nr() to retreive a task's pid_t. ChangeLog: - Fix Eric Biederman's comments - Use find_get_pid() to hold a reference to oz_pgrp and release while unmounting; separate out changes to autofs and autofs4. - Fix Cedric's comments: retain old prototype of parse_options() and move necessary change to its caller. Signed-off-by: Sukadev Bhattiprolu <sukadev@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Dave Hansen <haveblue@us.ibm.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: containers@lists.osdl.org --- fs/autofs/autofs_i.h | 4 ++-- fs/autofs/inode.c | 20 ++++++++++++++++---- fs/autofs/root.c | 6 ++++-- 3 files changed, 22 insertions(+), 8 deletions(-) Index: lx26-20-mm1/fs/autofs/autofs_i.h =================================================================== --- lx26-20-mm1.orig/fs/autofs/autofs_i.h 2007-02-16 14:32:49.000000000 -0800 +++ lx26-20-mm1/fs/autofs/autofs_i.h 2007-02-16 15:44:24.000000000 -0800 @@ -101,7 +101,7 @@ struct autofs_symlink { struct autofs_sb_info { u32 magic; struct file *pipe; - pid_t oz_pgrp; + struct pid *oz_pgrp; int catatonic; struct super_block *sb; unsigned long exp_timeout; @@ -122,7 +122,7 @@ static inline struct autofs_sb_info *aut filesystem without "magic".) */ static inline int autofs_oz_mode(struct autofs_sb_info *sbi) { - return sbi->catatonic || process_group(current) == sbi->oz_pgrp; + return sbi->catatonic || task_pgrp(current) == sbi->oz_pgrp; } /* Hash operations */ Index: lx26-20-mm1/fs/autofs/inode.c =================================================================== --- lx26-20-mm1.orig/fs/autofs/inode.c 2007-02-16 15:43:14.000000000 -0800 +++ lx26-20-mm1/fs/autofs/inode.c 2007-02-16 15:44:24.000000000 -0800 @@ -37,6 +37,8 @@ void autofs_kill_sb(struct super_block * if (!sbi->catatonic) autofs_catatonic_mode(sbi); /* Free wait queues, close pipe */ + put_pid(sbi->oz_pgrp); + autofs_hash_nuke(sbi); for (n = 0 ; n < AUTOFS_MAX_SYMLINKS ; n++) { if (test_bit(n, sbi->symlink_bitmap)) @@ -139,6 +141,7 @@ int autofs_fill_super(struct super_block int pipefd; struct autofs_sb_info *sbi; int minproto, maxproto; + pid_t pgid; sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); if (!sbi) @@ -150,7 +153,6 @@ int autofs_fill_super(struct super_block sbi->pipe = NULL; sbi->catatonic = 1; sbi->exp_timeout = 0; - sbi->oz_pgrp = process_group(current); autofs_initialize_hash(&sbi->dirhash); sbi->queues = NULL; memset(sbi->symlink_bitmap, 0, sizeof(long)*AUTOFS_SYMLINK_BITMAP_LEN); @@ -171,7 +173,7 @@ int autofs_fill_super(struct super_block /* Can this call block? - WTF cares? s is locked. */ if (parse_options(data, &pipefd, &root_inode->i_uid, - &root_inode->i_gid, &sbi->oz_pgrp, &minproto, + &root_inode->i_gid, &pgid, &minproto, &maxproto)) { printk("autofs: called with bogus options\n"); goto fail_dput; @@ -184,13 +186,21 @@ int autofs_fill_super(struct super_block goto fail_dput; } - DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, sbi->oz_pgrp)); + DPRINTK(("autofs: pipe fd = %d, pgrp = %u\n", pipefd, pgid)); + sbi->oz_pgrp = find_get_pid(pgid); + + if (!sbi->oz_pgrp) { + printk("autofs: could not find process group %d\n", pgid); + goto fail_dput; + } + pipe = fget(pipefd); if (!pipe) { printk("autofs: could not open pipe file descriptor\n"); - goto fail_dput; + goto fail_put_pid; } + if (!pipe->f_op || !pipe->f_op->write) goto fail_fput; sbi->pipe = pipe; @@ -205,6 +215,8 @@ int autofs_fill_super(struct super_block fail_fput: printk("autofs: pipe file descriptor does not contain proper ops\n"); fput(pipe); +fail_put_pid: + put_pid(sbi->oz_pgrp); fail_dput: dput(root); goto fail_free; Index: lx26-20-mm1/fs/autofs/root.c =================================================================== --- lx26-20-mm1.orig/fs/autofs/root.c 2007-02-16 15:43:14.000000000 -0800 +++ lx26-20-mm1/fs/autofs/root.c 2007-02-16 15:44:24.000000000 -0800 @@ -213,8 +213,10 @@ static struct dentry *autofs_root_lookup sbi = autofs_sbi(dir->i_sb); oz_mode = autofs_oz_mode(sbi); - DPRINTK(("autofs_lookup: pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d\n", - current->pid, process_group(current), sbi->catatonic, oz_mode)); + DPRINTK(("autofs_lookup: pid = %u, pgrp = %u, catatonic = %d, " + "oz_mode = %d\n", pid_nr(task_pid(current)), + process_group(current), sbi->catatonic, + oz_mode)); /* * Mark the dentry incomplete, but add it. This is needed so _______________________________________________ Containers mailing list Containers@lists.osdl.org https://lists.osdl.org/mailman/listinfo/containers