summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
Diffstat (limited to 'fs')
-rw-r--r--fs/file.c42
-rw-r--r--fs/fs-writeback.c4
-rw-r--r--fs/proc/array.c16
-rw-r--r--fs/proc/base.c9
-rw-r--r--fs/proc/meminfo.c7
5 files changed, 58 insertions, 20 deletions
diff --git a/fs/file.c b/fs/file.c
index 6c672ad329e9..c6986dce0334 100644
--- a/fs/file.c
+++ b/fs/file.c
@@ -56,6 +56,9 @@ static void free_fdtable_rcu(struct rcu_head *rcu)
__free_fdtable(container_of(rcu, struct fdtable, rcu));
}
+#define BITBIT_NR(nr) BITS_TO_LONGS(BITS_TO_LONGS(nr))
+#define BITBIT_SIZE(nr) (BITBIT_NR(nr) * sizeof(long))
+
/*
* Expand the fdset in the files_struct. Called with the files spinlock
* held for write.
@@ -77,6 +80,11 @@ static void copy_fdtable(struct fdtable *nfdt, struct fdtable *ofdt)
memset((char *)(nfdt->open_fds) + cpy, 0, set);
memcpy(nfdt->close_on_exec, ofdt->close_on_exec, cpy);
memset((char *)(nfdt->close_on_exec) + cpy, 0, set);
+
+ cpy = BITBIT_SIZE(ofdt->max_fds);
+ set = BITBIT_SIZE(nfdt->max_fds) - cpy;
+ memcpy(nfdt->full_fds_bits, ofdt->full_fds_bits, cpy);
+ memset(cpy+(char *)nfdt->full_fds_bits, 0, set);
}
static struct fdtable * alloc_fdtable(unsigned int nr)
@@ -115,12 +123,14 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
fdt->fd = data;
data = alloc_fdmem(max_t(size_t,
- 2 * nr / BITS_PER_BYTE, L1_CACHE_BYTES));
+ 2 * nr / BITS_PER_BYTE + BITBIT_SIZE(nr), L1_CACHE_BYTES));
if (!data)
goto out_arr;
fdt->open_fds = data;
data += nr / BITS_PER_BYTE;
fdt->close_on_exec = data;
+ data += nr / BITS_PER_BYTE;
+ fdt->full_fds_bits = data;
return fdt;
@@ -226,17 +236,22 @@ static inline void __set_close_on_exec(int fd, struct fdtable *fdt)
static inline void __clear_close_on_exec(int fd, struct fdtable *fdt)
{
- __clear_bit(fd, fdt->close_on_exec);
+ if (test_bit(fd, fdt->close_on_exec))
+ __clear_bit(fd, fdt->close_on_exec);
}
-static inline void __set_open_fd(int fd, struct fdtable *fdt)
+static inline void __set_open_fd(unsigned int fd, struct fdtable *fdt)
{
__set_bit(fd, fdt->open_fds);
+ fd /= BITS_PER_LONG;
+ if (!~fdt->open_fds[fd])
+ __set_bit(fd, fdt->full_fds_bits);
}
-static inline void __clear_open_fd(int fd, struct fdtable *fdt)
+static inline void __clear_open_fd(unsigned int fd, struct fdtable *fdt)
{
__clear_bit(fd, fdt->open_fds);
+ __clear_bit(fd / BITS_PER_LONG, fdt->full_fds_bits);
}
static int count_open_files(struct fdtable *fdt)
@@ -280,6 +295,7 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
new_fdt->max_fds = NR_OPEN_DEFAULT;
new_fdt->close_on_exec = newf->close_on_exec_init;
new_fdt->open_fds = newf->open_fds_init;
+ new_fdt->full_fds_bits = newf->full_fds_bits_init;
new_fdt->fd = &newf->fd_array[0];
spin_lock(&oldf->file_lock);
@@ -323,6 +339,7 @@ struct files_struct *dup_fd(struct files_struct *oldf, int *errorp)
memcpy(new_fdt->open_fds, old_fdt->open_fds, open_files / 8);
memcpy(new_fdt->close_on_exec, old_fdt->close_on_exec, open_files / 8);
+ memcpy(new_fdt->full_fds_bits, old_fdt->full_fds_bits, BITBIT_SIZE(open_files));
for (i = open_files; i != 0; i--) {
struct file *f = *old_fds++;
@@ -454,10 +471,25 @@ struct files_struct init_files = {
.fd = &init_files.fd_array[0],
.close_on_exec = init_files.close_on_exec_init,
.open_fds = init_files.open_fds_init,
+ .full_fds_bits = init_files.full_fds_bits_init,
},
.file_lock = __SPIN_LOCK_UNLOCKED(init_files.file_lock),
};
+static unsigned long find_next_fd(struct fdtable *fdt, unsigned long start)
+{
+ unsigned long maxfd = fdt->max_fds;
+ unsigned long maxbit = maxfd / BITS_PER_LONG;
+ unsigned long bitbit = start / BITS_PER_LONG;
+
+ bitbit = find_next_zero_bit(fdt->full_fds_bits, maxbit, bitbit) * BITS_PER_LONG;
+ if (bitbit > maxfd)
+ return maxfd;
+ if (bitbit > start)
+ start = bitbit;
+ return find_next_zero_bit(fdt->open_fds, maxfd, start);
+}
+
/*
* allocate a file descriptor, mark it busy.
*/
@@ -476,7 +508,7 @@ repeat:
fd = files->next_fd;
if (fd < fdt->max_fds)
- fd = find_next_zero_bit(fdt->open_fds, fdt->max_fds, fd);
+ fd = find_next_fd(fdt, fd);
/*
* N.B. For clone tasks sharing a files structure, this test
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 29e4599f6fc1..7378169e90be 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -779,8 +779,8 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi,
bool skip_if_busy)
{
struct bdi_writeback *last_wb = NULL;
- struct bdi_writeback *wb = list_entry_rcu(&bdi->wb_list,
- struct bdi_writeback, bdi_node);
+ struct bdi_writeback *wb = list_entry(&bdi->wb_list,
+ struct bdi_writeback, bdi_node);
might_sleep();
restart:
diff --git a/fs/proc/array.c b/fs/proc/array.c
index f60f0121e331..eed2050db9be 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -375,7 +375,7 @@ int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
struct pid *pid, struct task_struct *task, int whole)
{
- unsigned long vsize, eip, esp, wchan = ~0UL;
+ unsigned long vsize, eip, esp, wchan = 0;
int priority, nice;
int tty_pgrp = -1, tty_nr = 0;
sigset_t sigign, sigcatch;
@@ -507,7 +507,19 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
seq_put_decimal_ull(m, ' ', task->blocked.sig[0] & 0x7fffffffUL);
seq_put_decimal_ull(m, ' ', sigign.sig[0] & 0x7fffffffUL);
seq_put_decimal_ull(m, ' ', sigcatch.sig[0] & 0x7fffffffUL);
- seq_put_decimal_ull(m, ' ', wchan);
+
+ /*
+ * We used to output the absolute kernel address, but that's an
+ * information leak - so instead we show a 0/1 flag here, to signal
+ * to user-space whether there's a wchan field in /proc/PID/wchan.
+ *
+ * This works with older implementations of procps as well.
+ */
+ if (wchan)
+ seq_puts(m, " 1");
+ else
+ seq_puts(m, " 0");
+
seq_put_decimal_ull(m, ' ', 0);
seq_put_decimal_ull(m, ' ', 0);
seq_put_decimal_ll(m, ' ', task->exit_signal);
diff --git a/fs/proc/base.c b/fs/proc/base.c
index b25eee4cead5..29595af32866 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -430,13 +430,10 @@ static int proc_pid_wchan(struct seq_file *m, struct pid_namespace *ns,
wchan = get_wchan(task);
- if (lookup_symbol_name(wchan, symname) < 0) {
- if (!ptrace_may_access(task, PTRACE_MODE_READ))
- return 0;
- seq_printf(m, "%lu", wchan);
- } else {
+ if (wchan && ptrace_may_access(task, PTRACE_MODE_READ) && !lookup_symbol_name(wchan, symname))
seq_printf(m, "%s", symname);
- }
+ else
+ seq_putc(m, '0');
return 0;
}
diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c
index d3ebf2e61853..9155a5a0d3b9 100644
--- a/fs/proc/meminfo.c
+++ b/fs/proc/meminfo.c
@@ -27,7 +27,6 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
{
struct sysinfo i;
unsigned long committed;
- struct vmalloc_info vmi;
long cached;
long available;
unsigned long pagecache;
@@ -49,8 +48,6 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
if (cached < 0)
cached = 0;
- get_vmalloc_info(&vmi);
-
for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++)
pages[lru] = global_page_state(NR_LRU_BASE + lru);
@@ -191,8 +188,8 @@ static int meminfo_proc_show(struct seq_file *m, void *v)
K(vm_commit_limit()),
K(committed),
(unsigned long)VMALLOC_TOTAL >> 10,
- vmi.used >> 10,
- vmi.largest_chunk >> 10
+ 0ul, // used to be vmalloc 'used'
+ 0ul // used to be vmalloc 'largest_chunk'
#ifdef CONFIG_MEMORY_FAILURE
, atomic_long_read(&num_poisoned_pages) << (PAGE_SHIFT - 10)
#endif