[RFC][PATCH 2/3] Replace pid_t in autofs4 with struct pid reference
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. - Also rollback my earlier change to autofs_wait_queue (pid and tgid in the wait queue are just used to write to a userspace daemon's pipe). --- From: Sukadev Bhattiprolu <sukadev@us.ibm.com> Subject: Replace pid_t in autofs4 with struct pid reference. Make autofs4 container-friendly by caching struct pid reference rather than pid_t. 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/autofs4/autofs_i.h | 6 +++--- fs/autofs4/inode.c | 29 ++++++++++++++++++++--------- fs/autofs4/root.c | 3 ++- fs/autofs4/waitq.c | 4 ++-- 4 files changed, 27 insertions(+), 15 deletions(-) Index: lx26-20-rc4-mm1/fs/autofs4/autofs_i.h =================================================================== --- lx26-20-rc4-mm1.orig/fs/autofs4/autofs_i.h 2007-01-24 18:39:28.172066416 -0800 +++ lx26-20-rc4-mm1/fs/autofs4/autofs_i.h 2007-01-24 18:41:56.260553544 -0800 @@ -35,7 +35,7 @@ /* #define DEBUG */ #ifdef DEBUG -#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , current->pid , __FUNCTION__ , ##args); } while(0) +#define DPRINTK(fmt,args...) do { printk(KERN_DEBUG "pid %d: %s: " fmt "\n" , pid_nr(task_pid(current)), __FUNCTION__ , ##args); } while(0) #else #define DPRINTK(fmt,args...) do {} while(0) #endif @@ -96,7 +96,7 @@ struct autofs_sb_info { u32 magic; int pipefd; struct file *pipe; - pid_t oz_pgrp; + struct pid *oz_pgrp; int catatonic; int version; int sub_version; @@ -127,7 +127,7 @@ static inline struct autofs_info *autofs filesystem without "magic".) */ static inline int autofs4_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; } /* Does a dentry have some pending activity? */ Index: lx26-20-rc4-mm1/fs/autofs4/inode.c =================================================================== --- lx26-20-rc4-mm1.orig/fs/autofs4/inode.c 2007-01-24 18:39:28.173066264 -0800 +++ lx26-20-rc4-mm1/fs/autofs4/inode.c 2007-01-24 18:44:56.311181688 -0800 @@ -163,6 +163,8 @@ void autofs4_kill_sb(struct super_block if ( !sbi->catatonic ) autofs4_catatonic_mode(sbi); /* Free wait queues, close pipe */ + put_pid(sbi->oz_pgrp); + /* Clean up and release dangling references */ autofs4_force_release(sbi); @@ -181,7 +183,7 @@ static int autofs4_show_options(struct s return 0; seq_printf(m, ",fd=%d", sbi->pipefd); - seq_printf(m, ",pgrp=%d", sbi->oz_pgrp); + seq_printf(m, ",pgrp=%d", pid_nr(sbi->oz_pgrp)); seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); seq_printf(m, ",minproto=%d", sbi->min_proto); seq_printf(m, ",maxproto=%d", sbi->max_proto); @@ -218,16 +220,17 @@ static match_table_t tokens = { }; static int parse_options(char *options, int *pipefd, uid_t *uid, gid_t *gid, - pid_t *pgrp, unsigned int *type, + struct pid **pgrp, unsigned int *type, int *minproto, int *maxproto) { char *p; substring_t args[MAX_OPT_ARGS]; int option; + pid_t pgid; *uid = current->uid; *gid = current->gid; - *pgrp = process_group(current); + pgid = process_group(current); *minproto = AUTOFS_MIN_PROTO_VERSION; *maxproto = AUTOFS_MAX_PROTO_VERSION; @@ -261,7 +264,7 @@ static int parse_options(char *options, case Opt_pgrp: if (match_int(args, &option)) return 1; - *pgrp = option; + pgid = option; break; case Opt_minproto: if (match_int(args, &option)) @@ -286,7 +289,13 @@ static int parse_options(char *options, return 1; } } - return (*pipefd < 0); + + if (*pipefd < 0) + return 1; + + *pgrp = find_get_pid(pgid); + + return (*pgrp == NULL); } static struct autofs_info *autofs4_mkroot(struct autofs_sb_info *sbi) @@ -326,7 +335,7 @@ int autofs4_fill_super(struct super_bloc sbi->pipe = NULL; sbi->catatonic = 1; sbi->exp_timeout = 0; - sbi->oz_pgrp = process_group(current); + sbi->oz_pgrp = NULL; sbi->sb = s; sbi->version = 0; sbi->sub_version = 0; @@ -381,7 +390,7 @@ int autofs4_fill_super(struct super_bloc "daemon (%d, %d) kernel (%d, %d)\n", sbi->min_proto, sbi->max_proto, AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION); - goto fail_dput; + goto fail_put_pid; } /* Establish highest kernel protocol version */ @@ -391,12 +400,12 @@ int autofs4_fill_super(struct super_bloc sbi->version = sbi->max_proto; sbi->sub_version = AUTOFS_PROTO_SUBVERSION; - DPRINTK("pipe fd = %d, pgrp = %u", pipefd, sbi->oz_pgrp); + DPRINTK("pipe fd = %d, pgrp = %u", pipefd, pid_nr(sbi->oz_pgrp)); 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; @@ -417,6 +426,8 @@ fail_fput: printk("autofs: pipe file descriptor does not contain proper ops\n"); fput(pipe); /* fall through */ +fail_put_pid: + put_pid(sbi->oz_pgrp); fail_dput: dput(root); goto fail_free; Index: lx26-20-rc4-mm1/fs/autofs4/root.c =================================================================== --- lx26-20-rc4-mm1.orig/fs/autofs4/root.c 2007-01-24 18:39:28.173066264 -0800 +++ lx26-20-rc4-mm1/fs/autofs4/root.c 2007-01-24 18:44:56.310181840 -0800 @@ -495,7 +495,8 @@ static struct dentry *autofs4_lookup(str oz_mode = autofs4_oz_mode(sbi); DPRINTK("pid = %u, pgrp = %u, catatonic = %d, oz_mode = %d", - current->pid, process_group(current), sbi->catatonic, oz_mode); + pid_nr(task_pid(current)), process_group(current), + sbi->catatonic, oz_mode); /* * Mark the dentry incomplete, but add it. This is needed so Index: lx26-20-rc4-mm1/fs/autofs4/waitq.c =================================================================== --- lx26-20-rc4-mm1.orig/fs/autofs4/waitq.c 2007-01-24 18:39:28.173066264 -0800 +++ lx26-20-rc4-mm1/fs/autofs4/waitq.c 2007-01-24 18:41:56.262553240 -0800 @@ -292,8 +292,8 @@ int autofs4_wait(struct autofs_sb_info * wq->ino = autofs4_get_ino(sbi); wq->uid = current->uid; wq->gid = current->gid; - wq->pid = current->pid; - wq->tgid = current->tgid; + wq->pid = pid_nr(task_pid(current)); + wq->tgid = pid_nr(task_tgid(current)); wq->status = -EINTR; /* Status return if interrupted */ atomic_set(&wq->wait_ctr, 2); mutex_unlock(&sbi->wq_mutex); _______________________________________________ Containers mailing list Containers@lists.osdl.org https://lists.osdl.org/mailman/listinfo/containers