541 lines
12 KiB
C
541 lines
12 KiB
C
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// SPDX-License-Identifier: GPL-2.0
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/*
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* (C) 2001 Clemson University and The University of Chicago
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*
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* See COPYING in top-level directory.
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*/
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#include "protocol.h"
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#include "orangefs-kernel.h"
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#include "orangefs-bufmap.h"
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struct slot_map {
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int c;
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wait_queue_head_t q;
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int count;
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unsigned long *map;
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};
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static struct slot_map rw_map = {
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.c = -1,
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.q = __WAIT_QUEUE_HEAD_INITIALIZER(rw_map.q)
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};
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static struct slot_map readdir_map = {
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.c = -1,
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.q = __WAIT_QUEUE_HEAD_INITIALIZER(readdir_map.q)
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};
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static void install(struct slot_map *m, int count, unsigned long *map)
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{
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spin_lock(&m->q.lock);
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m->c = m->count = count;
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m->map = map;
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wake_up_all_locked(&m->q);
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spin_unlock(&m->q.lock);
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}
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static void mark_killed(struct slot_map *m)
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{
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spin_lock(&m->q.lock);
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m->c -= m->count + 1;
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spin_unlock(&m->q.lock);
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}
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static void run_down(struct slot_map *m)
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{
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DEFINE_WAIT(wait);
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spin_lock(&m->q.lock);
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if (m->c != -1) {
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for (;;) {
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if (likely(list_empty(&wait.entry)))
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__add_wait_queue_entry_tail(&m->q, &wait);
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set_current_state(TASK_UNINTERRUPTIBLE);
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if (m->c == -1)
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break;
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spin_unlock(&m->q.lock);
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schedule();
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spin_lock(&m->q.lock);
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}
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__remove_wait_queue(&m->q, &wait);
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__set_current_state(TASK_RUNNING);
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}
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m->map = NULL;
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spin_unlock(&m->q.lock);
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}
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static void put(struct slot_map *m, int slot)
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{
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int v;
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spin_lock(&m->q.lock);
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__clear_bit(slot, m->map);
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v = ++m->c;
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if (v > 0)
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wake_up_locked(&m->q);
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if (unlikely(v == -1)) /* finished dying */
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wake_up_all_locked(&m->q);
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spin_unlock(&m->q.lock);
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}
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static int wait_for_free(struct slot_map *m)
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{
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long left = slot_timeout_secs * HZ;
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DEFINE_WAIT(wait);
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do {
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long n = left, t;
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if (likely(list_empty(&wait.entry)))
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__add_wait_queue_entry_tail_exclusive(&m->q, &wait);
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set_current_state(TASK_INTERRUPTIBLE);
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if (m->c > 0)
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break;
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if (m->c < 0) {
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/* we are waiting for map to be installed */
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/* it would better be there soon, or we go away */
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if (n > ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ)
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n = ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ;
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}
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spin_unlock(&m->q.lock);
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t = schedule_timeout(n);
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spin_lock(&m->q.lock);
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if (unlikely(!t) && n != left && m->c < 0)
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left = t;
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else
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left = t + (left - n);
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if (unlikely(signal_pending(current)))
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left = -EINTR;
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} while (left > 0);
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if (!list_empty(&wait.entry))
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list_del(&wait.entry);
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else if (left <= 0 && waitqueue_active(&m->q))
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__wake_up_locked_key(&m->q, TASK_INTERRUPTIBLE, NULL);
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__set_current_state(TASK_RUNNING);
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if (likely(left > 0))
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return 0;
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return left < 0 ? -EINTR : -ETIMEDOUT;
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}
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static int get(struct slot_map *m)
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{
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int res = 0;
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spin_lock(&m->q.lock);
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if (unlikely(m->c <= 0))
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res = wait_for_free(m);
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if (likely(!res)) {
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m->c--;
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res = find_first_zero_bit(m->map, m->count);
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__set_bit(res, m->map);
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}
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spin_unlock(&m->q.lock);
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return res;
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}
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/* used to describe mapped buffers */
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struct orangefs_bufmap_desc {
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void __user *uaddr; /* user space address pointer */
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struct page **page_array; /* array of mapped pages */
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int array_count; /* size of above arrays */
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struct list_head list_link;
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};
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static struct orangefs_bufmap {
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int desc_size;
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int desc_shift;
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int desc_count;
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int total_size;
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int page_count;
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struct page **page_array;
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struct orangefs_bufmap_desc *desc_array;
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/* array to track usage of buffer descriptors */
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unsigned long *buffer_index_array;
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/* array to track usage of buffer descriptors for readdir */
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#define N DIV_ROUND_UP(ORANGEFS_READDIR_DEFAULT_DESC_COUNT, BITS_PER_LONG)
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unsigned long readdir_index_array[N];
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#undef N
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} *__orangefs_bufmap;
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static DEFINE_SPINLOCK(orangefs_bufmap_lock);
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static void
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orangefs_bufmap_unmap(struct orangefs_bufmap *bufmap)
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{
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int i;
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for (i = 0; i < bufmap->page_count; i++)
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put_page(bufmap->page_array[i]);
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}
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static void
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orangefs_bufmap_free(struct orangefs_bufmap *bufmap)
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{
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kfree(bufmap->page_array);
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kfree(bufmap->desc_array);
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kfree(bufmap->buffer_index_array);
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kfree(bufmap);
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}
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/*
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* XXX: Can the size and shift change while the caller gives up the
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* XXX: lock between calling this and doing something useful?
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*/
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int orangefs_bufmap_size_query(void)
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{
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struct orangefs_bufmap *bufmap;
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int size = 0;
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spin_lock(&orangefs_bufmap_lock);
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bufmap = __orangefs_bufmap;
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if (bufmap)
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size = bufmap->desc_size;
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spin_unlock(&orangefs_bufmap_lock);
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return size;
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}
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int orangefs_bufmap_shift_query(void)
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{
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struct orangefs_bufmap *bufmap;
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int shift = 0;
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spin_lock(&orangefs_bufmap_lock);
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bufmap = __orangefs_bufmap;
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if (bufmap)
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shift = bufmap->desc_shift;
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spin_unlock(&orangefs_bufmap_lock);
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return shift;
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}
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static DECLARE_WAIT_QUEUE_HEAD(bufmap_waitq);
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static DECLARE_WAIT_QUEUE_HEAD(readdir_waitq);
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static struct orangefs_bufmap *
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orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc)
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{
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struct orangefs_bufmap *bufmap;
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bufmap = kzalloc(sizeof(*bufmap), GFP_KERNEL);
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if (!bufmap)
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goto out;
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bufmap->total_size = user_desc->total_size;
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bufmap->desc_count = user_desc->count;
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bufmap->desc_size = user_desc->size;
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bufmap->desc_shift = ilog2(bufmap->desc_size);
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bufmap->buffer_index_array =
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kzalloc(DIV_ROUND_UP(bufmap->desc_count, BITS_PER_LONG), GFP_KERNEL);
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if (!bufmap->buffer_index_array)
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goto out_free_bufmap;
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bufmap->desc_array =
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kcalloc(bufmap->desc_count, sizeof(struct orangefs_bufmap_desc),
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GFP_KERNEL);
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if (!bufmap->desc_array)
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goto out_free_index_array;
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bufmap->page_count = bufmap->total_size / PAGE_SIZE;
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/* allocate storage to track our page mappings */
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bufmap->page_array =
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kcalloc(bufmap->page_count, sizeof(struct page *), GFP_KERNEL);
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if (!bufmap->page_array)
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goto out_free_desc_array;
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return bufmap;
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out_free_desc_array:
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kfree(bufmap->desc_array);
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out_free_index_array:
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kfree(bufmap->buffer_index_array);
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out_free_bufmap:
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kfree(bufmap);
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out:
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return NULL;
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}
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static int
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orangefs_bufmap_map(struct orangefs_bufmap *bufmap,
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struct ORANGEFS_dev_map_desc *user_desc)
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{
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||
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int pages_per_desc = bufmap->desc_size / PAGE_SIZE;
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int offset = 0, ret, i;
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/* map the pages */
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ret = get_user_pages_fast((unsigned long)user_desc->ptr,
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bufmap->page_count, 1, bufmap->page_array);
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if (ret < 0)
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return ret;
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if (ret != bufmap->page_count) {
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gossip_err("orangefs error: asked for %d pages, only got %d.\n",
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bufmap->page_count, ret);
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for (i = 0; i < ret; i++) {
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SetPageError(bufmap->page_array[i]);
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put_page(bufmap->page_array[i]);
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}
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return -ENOMEM;
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||
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}
|
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|
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/*
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* ideally we want to get kernel space pointers for each page, but
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* we can't kmap that many pages at once if highmem is being used.
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* so instead, we just kmap/kunmap the page address each time the
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* kaddr is needed.
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*/
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for (i = 0; i < bufmap->page_count; i++)
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flush_dcache_page(bufmap->page_array[i]);
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|
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/* build a list of available descriptors */
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for (offset = 0, i = 0; i < bufmap->desc_count; i++) {
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bufmap->desc_array[i].page_array = &bufmap->page_array[offset];
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bufmap->desc_array[i].array_count = pages_per_desc;
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bufmap->desc_array[i].uaddr =
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(user_desc->ptr + (i * pages_per_desc * PAGE_SIZE));
|
||
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offset += pages_per_desc;
|
||
|
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}
|
||
|
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|
||
|
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return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* orangefs_bufmap_initialize()
|
||
|
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*
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||
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* initializes the mapped buffer interface
|
||
|
|
*
|
||
|
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* returns 0 on success, -errno on failure
|
||
|
|
*/
|
||
|
|
int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc)
|
||
|
|
{
|
||
|
|
struct orangefs_bufmap *bufmap;
|
||
|
|
int ret = -EINVAL;
|
||
|
|
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG,
|
||
|
|
"orangefs_bufmap_initialize: called (ptr ("
|
||
|
|
"%p) sz (%d) cnt(%d).\n",
|
||
|
|
user_desc->ptr,
|
||
|
|
user_desc->size,
|
||
|
|
user_desc->count);
|
||
|
|
|
||
|
|
if (user_desc->total_size < 0 ||
|
||
|
|
user_desc->size < 0 ||
|
||
|
|
user_desc->count < 0)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* sanity check alignment and size of buffer that caller wants to
|
||
|
|
* work with
|
||
|
|
*/
|
||
|
|
if (PAGE_ALIGN((unsigned long)user_desc->ptr) !=
|
||
|
|
(unsigned long)user_desc->ptr) {
|
||
|
|
gossip_err("orangefs error: memory alignment (front). %p\n",
|
||
|
|
user_desc->ptr);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (PAGE_ALIGN(((unsigned long)user_desc->ptr + user_desc->total_size))
|
||
|
|
!= (unsigned long)(user_desc->ptr + user_desc->total_size)) {
|
||
|
|
gossip_err("orangefs error: memory alignment (back).(%p + %d)\n",
|
||
|
|
user_desc->ptr,
|
||
|
|
user_desc->total_size);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (user_desc->total_size != (user_desc->size * user_desc->count)) {
|
||
|
|
gossip_err("orangefs error: user provided an oddly sized buffer: (%d, %d, %d)\n",
|
||
|
|
user_desc->total_size,
|
||
|
|
user_desc->size,
|
||
|
|
user_desc->count);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((user_desc->size % PAGE_SIZE) != 0) {
|
||
|
|
gossip_err("orangefs error: bufmap size not page size divisible (%d).\n",
|
||
|
|
user_desc->size);
|
||
|
|
goto out;
|
||
|
|
}
|
||
|
|
|
||
|
|
ret = -ENOMEM;
|
||
|
|
bufmap = orangefs_bufmap_alloc(user_desc);
|
||
|
|
if (!bufmap)
|
||
|
|
goto out;
|
||
|
|
|
||
|
|
ret = orangefs_bufmap_map(bufmap, user_desc);
|
||
|
|
if (ret)
|
||
|
|
goto out_free_bufmap;
|
||
|
|
|
||
|
|
|
||
|
|
spin_lock(&orangefs_bufmap_lock);
|
||
|
|
if (__orangefs_bufmap) {
|
||
|
|
spin_unlock(&orangefs_bufmap_lock);
|
||
|
|
gossip_err("orangefs: error: bufmap already initialized.\n");
|
||
|
|
ret = -EINVAL;
|
||
|
|
goto out_unmap_bufmap;
|
||
|
|
}
|
||
|
|
__orangefs_bufmap = bufmap;
|
||
|
|
install(&rw_map,
|
||
|
|
bufmap->desc_count,
|
||
|
|
bufmap->buffer_index_array);
|
||
|
|
install(&readdir_map,
|
||
|
|
ORANGEFS_READDIR_DEFAULT_DESC_COUNT,
|
||
|
|
bufmap->readdir_index_array);
|
||
|
|
spin_unlock(&orangefs_bufmap_lock);
|
||
|
|
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG,
|
||
|
|
"orangefs_bufmap_initialize: exiting normally\n");
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
out_unmap_bufmap:
|
||
|
|
orangefs_bufmap_unmap(bufmap);
|
||
|
|
out_free_bufmap:
|
||
|
|
orangefs_bufmap_free(bufmap);
|
||
|
|
out:
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* orangefs_bufmap_finalize()
|
||
|
|
*
|
||
|
|
* shuts down the mapped buffer interface and releases any resources
|
||
|
|
* associated with it
|
||
|
|
*
|
||
|
|
* no return value
|
||
|
|
*/
|
||
|
|
void orangefs_bufmap_finalize(void)
|
||
|
|
{
|
||
|
|
struct orangefs_bufmap *bufmap = __orangefs_bufmap;
|
||
|
|
if (!bufmap)
|
||
|
|
return;
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG, "orangefs_bufmap_finalize: called\n");
|
||
|
|
mark_killed(&rw_map);
|
||
|
|
mark_killed(&readdir_map);
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG,
|
||
|
|
"orangefs_bufmap_finalize: exiting normally\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
void orangefs_bufmap_run_down(void)
|
||
|
|
{
|
||
|
|
struct orangefs_bufmap *bufmap = __orangefs_bufmap;
|
||
|
|
if (!bufmap)
|
||
|
|
return;
|
||
|
|
run_down(&rw_map);
|
||
|
|
run_down(&readdir_map);
|
||
|
|
spin_lock(&orangefs_bufmap_lock);
|
||
|
|
__orangefs_bufmap = NULL;
|
||
|
|
spin_unlock(&orangefs_bufmap_lock);
|
||
|
|
orangefs_bufmap_unmap(bufmap);
|
||
|
|
orangefs_bufmap_free(bufmap);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* orangefs_bufmap_get()
|
||
|
|
*
|
||
|
|
* gets a free mapped buffer descriptor, will sleep until one becomes
|
||
|
|
* available if necessary
|
||
|
|
*
|
||
|
|
* returns slot on success, -errno on failure
|
||
|
|
*/
|
||
|
|
int orangefs_bufmap_get(void)
|
||
|
|
{
|
||
|
|
return get(&rw_map);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* orangefs_bufmap_put()
|
||
|
|
*
|
||
|
|
* returns a mapped buffer descriptor to the collection
|
||
|
|
*
|
||
|
|
* no return value
|
||
|
|
*/
|
||
|
|
void orangefs_bufmap_put(int buffer_index)
|
||
|
|
{
|
||
|
|
put(&rw_map, buffer_index);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* orangefs_readdir_index_get()
|
||
|
|
*
|
||
|
|
* gets a free descriptor, will sleep until one becomes
|
||
|
|
* available if necessary.
|
||
|
|
* Although the readdir buffers are not mapped into kernel space
|
||
|
|
* we could do that at a later point of time. Regardless, these
|
||
|
|
* indices are used by the client-core.
|
||
|
|
*
|
||
|
|
* returns slot on success, -errno on failure
|
||
|
|
*/
|
||
|
|
int orangefs_readdir_index_get(void)
|
||
|
|
{
|
||
|
|
return get(&readdir_map);
|
||
|
|
}
|
||
|
|
|
||
|
|
void orangefs_readdir_index_put(int buffer_index)
|
||
|
|
{
|
||
|
|
put(&readdir_map, buffer_index);
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* we've been handed an iovec, we need to copy it to
|
||
|
|
* the shared memory descriptor at "buffer_index".
|
||
|
|
*/
|
||
|
|
int orangefs_bufmap_copy_from_iovec(struct iov_iter *iter,
|
||
|
|
int buffer_index,
|
||
|
|
size_t size)
|
||
|
|
{
|
||
|
|
struct orangefs_bufmap_desc *to;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG,
|
||
|
|
"%s: buffer_index:%d: size:%zu:\n",
|
||
|
|
__func__, buffer_index, size);
|
||
|
|
|
||
|
|
to = &__orangefs_bufmap->desc_array[buffer_index];
|
||
|
|
for (i = 0; size; i++) {
|
||
|
|
struct page *page = to->page_array[i];
|
||
|
|
size_t n = size;
|
||
|
|
if (n > PAGE_SIZE)
|
||
|
|
n = PAGE_SIZE;
|
||
|
|
if (copy_page_from_iter(page, 0, n, iter) != n)
|
||
|
|
return -EFAULT;
|
||
|
|
size -= n;
|
||
|
|
}
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* we've been handed an iovec, we need to fill it from
|
||
|
|
* the shared memory descriptor at "buffer_index".
|
||
|
|
*/
|
||
|
|
int orangefs_bufmap_copy_to_iovec(struct iov_iter *iter,
|
||
|
|
int buffer_index,
|
||
|
|
size_t size)
|
||
|
|
{
|
||
|
|
struct orangefs_bufmap_desc *from;
|
||
|
|
int i;
|
||
|
|
|
||
|
|
from = &__orangefs_bufmap->desc_array[buffer_index];
|
||
|
|
gossip_debug(GOSSIP_BUFMAP_DEBUG,
|
||
|
|
"%s: buffer_index:%d: size:%zu:\n",
|
||
|
|
__func__, buffer_index, size);
|
||
|
|
|
||
|
|
|
||
|
|
for (i = 0; size; i++) {
|
||
|
|
struct page *page = from->page_array[i];
|
||
|
|
size_t n = size;
|
||
|
|
if (n > PAGE_SIZE)
|
||
|
|
n = PAGE_SIZE;
|
||
|
|
n = copy_page_to_iter(page, 0, n, iter);
|
||
|
|
if (!n)
|
||
|
|
return -EFAULT;
|
||
|
|
size -= n;
|
||
|
|
}
|
||
|
|
return 0;
|
||
|
|
}
|