diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index dec9945..9b390d7 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -989,6 +989,14 @@ nr_inodes Denotes the number of inodes the system has allocated. This number will grow and shrink dynamically. +nr_open +------- + +Denotes the maximum number of file-handles a process can +allocate. Default value is 1024*1024 (1048576) which should be +enough for most machines. Actual limit depends on RLIMIT_NOFILE +resource limit. + nr_free_inodes -------------- diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt index aa986a3..f992543 100644 --- a/Documentation/sysctl/fs.txt +++ b/Documentation/sysctl/fs.txt @@ -23,6 +23,7 @@ Currently, these files are in /proc/sys/fs: - inode-max - inode-nr - inode-state +- nr_open - overflowuid - overflowgid - suid_dumpable @@ -91,6 +92,15 @@ usage of file handles and you don't need to increase the maximum. ============================================================== +nr_open: + +This denotes the maximum number of file-handles a process can +allocate. Default value is 1024*1024 (1048576) which should be +enough for most machines. Actual limit depends on RLIMIT_NOFILE +resource limit. + +============================================================== + inode-max, inode-nr & inode-state: As with file handles, the kernel allocates the inode structures diff --git a/fs/file.c b/fs/file.c index c5575de..5110acb 100644 --- a/fs/file.c +++ b/fs/file.c @@ -24,6 +24,8 @@ struct fdtable_defer { struct fdtable *next; }; +int sysctl_nr_open __read_mostly = 1024*1024; + /* * We use this list to defer free fdtables that have vmalloced * sets/arrays. By keeping a per-cpu list, we avoid having to embed @@ -147,8 +149,8 @@ static struct fdtable * alloc_fdtable(unsigned int nr) nr /= (1024 / sizeof(struct file *)); nr = roundup_pow_of_two(nr + 1); nr *= (1024 / sizeof(struct file *)); - if (nr > NR_OPEN) - nr = NR_OPEN; + if (nr > sysctl_nr_open) + nr = sysctl_nr_open; fdt = kmalloc(sizeof(struct fdtable), GFP_KERNEL); if (!fdt) @@ -233,7 +235,7 @@ int expand_files(struct files_struct *files, int nr) if (nr < fdt->max_fds) return 0; /* Can we expand? */ - if (nr >= NR_OPEN) + if (nr >= sysctl_nr_open) return -EMFILE; /* All good, so we try */ diff --git a/include/linux/fs.h b/include/linux/fs.h index b3ec4a4..1cda287 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -21,7 +21,7 @@ /* Fixed constants first: */ #undef NR_OPEN -#define NR_OPEN (1024*1024) /* Absolute upper limit on fd num */ +extern int sysctl_nr_open; #define INR_OPEN 1024 /* Initial setting for nfile rlimits */ #define BLOCK_SIZE_BITS 10 diff --git a/kernel/sys.c b/kernel/sys.c index d1fe71e..99c6ce1 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1472,7 +1472,7 @@ asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim) if ((new_rlim.rlim_max > old_rlim->rlim_max) && !capable(CAP_SYS_RESOURCE)) return -EPERM; - if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > NR_OPEN) + if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) return -EPERM; retval = security_task_setrlimit(resource, &new_rlim); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 0deed82..de22f7b 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1127,6 +1127,14 @@ static struct ctl_table fs_table[] = { .proc_handler = &proc_dointvec, }, { + .ctl_name = CTL_UNNUMBERED, + .procname = "nr_open", + .data = &sysctl_nr_open, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { .ctl_name = FS_DENTRY, .procname = "dentry-state", .data = &dentry_stat,