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author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-22 23:26:10 (GMT) |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-22 23:26:10 (GMT) |
commit | ab70a1d7c7fc6665d83f41b5ce790ff8376e0b81 (patch) | |
tree | dee8acafa2dfb87cde4ddba68eff5e1c75557469 /net | |
parent | 0adfc56ce8fdc5c17630434e49f30536ba7b8559 (diff) | |
parent | 68da9ba4eeadae86ad42e52b80822fbd56971267 (diff) | |
download | linux-ab70a1d7c7fc6665d83f41b5ce790ff8376e0b81.tar.xz |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
[net/9p]: Introduce basic flow-control for VirtIO transport.
9p: use the updated offset given by generic_write_checks
[net/9p] Don't re-pin pages on retrying virtqueue_add_buf().
[net/9p] Set the condition just before waking up.
[net/9p] unconditional wake_up to proc waiting for space on VirtIO ring
fs/9p: Add v9fs_dentry2v9ses
fs/9p: Attach writeback_fid on first open with WR flag
fs/9p: Open writeback fid in O_SYNC mode
fs/9p: Use truncate_setsize instead of vmtruncate
net/9p: Fix compile warning
net/9p: Convert the in the 9p rpc call path to GFP_NOFS
fs/9p: Fix race in initializing writeback fid
Diffstat (limited to 'net')
-rw-r--r-- | net/9p/client.c | 10 | ||||
-rw-r--r-- | net/9p/protocol.c | 6 | ||||
-rw-r--r-- | net/9p/trans_common.c | 10 | ||||
-rw-r--r-- | net/9p/trans_fd.c | 2 | ||||
-rw-r--r-- | net/9p/trans_rdma.c | 6 | ||||
-rw-r--r-- | net/9p/trans_virtio.c | 72 | ||||
-rw-r--r-- | net/9p/util.c | 2 |
7 files changed, 64 insertions, 44 deletions
diff --git a/net/9p/client.c b/net/9p/client.c index 347ec0c..2ccbf04 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -223,7 +223,7 @@ static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag) req = &c->reqs[row][col]; if (!req->tc) { - req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL); + req->wq = kmalloc(sizeof(wait_queue_head_t), GFP_NOFS); if (!req->wq) { printk(KERN_ERR "Couldn't grow tag array\n"); return ERR_PTR(-ENOMEM); @@ -233,17 +233,17 @@ static struct p9_req_t *p9_tag_alloc(struct p9_client *c, u16 tag) P9_TRANS_PREF_PAYLOAD_SEP) { int alloc_msize = min(c->msize, 4096); req->tc = kmalloc(sizeof(struct p9_fcall)+alloc_msize, - GFP_KERNEL); + GFP_NOFS); req->tc->capacity = alloc_msize; req->rc = kmalloc(sizeof(struct p9_fcall)+alloc_msize, - GFP_KERNEL); + GFP_NOFS); req->rc->capacity = alloc_msize; } else { req->tc = kmalloc(sizeof(struct p9_fcall)+c->msize, - GFP_KERNEL); + GFP_NOFS); req->tc->capacity = c->msize; req->rc = kmalloc(sizeof(struct p9_fcall)+c->msize, - GFP_KERNEL); + GFP_NOFS); req->rc->capacity = c->msize; } if ((!req->tc) || (!req->rc)) { diff --git a/net/9p/protocol.c b/net/9p/protocol.c index 2ce515b..8a4084f 100644 --- a/net/9p/protocol.c +++ b/net/9p/protocol.c @@ -205,7 +205,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt, if (errcode) break; - *sptr = kmalloc(len + 1, GFP_KERNEL); + *sptr = kmalloc(len + 1, GFP_NOFS); if (*sptr == NULL) { errcode = -EFAULT; break; @@ -273,7 +273,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt, if (!errcode) { *wnames = kmalloc(sizeof(char *) * *nwname, - GFP_KERNEL); + GFP_NOFS); if (!*wnames) errcode = -ENOMEM; } @@ -317,7 +317,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt, *wqids = kmalloc(*nwqid * sizeof(struct p9_qid), - GFP_KERNEL); + GFP_NOFS); if (*wqids == NULL) errcode = -ENOMEM; } diff --git a/net/9p/trans_common.c b/net/9p/trans_common.c index d62b9aa..9172ab7 100644 --- a/net/9p/trans_common.c +++ b/net/9p/trans_common.c @@ -41,9 +41,9 @@ EXPORT_SYMBOL(p9_release_req_pages); int p9_nr_pages(struct p9_req_t *req) { - int start_page, end_page; - start_page = (unsigned long long)req->tc->pubuf >> PAGE_SHIFT; - end_page = ((unsigned long long)req->tc->pubuf + req->tc->pbuf_size + + unsigned long start_page, end_page; + start_page = (unsigned long)req->tc->pubuf >> PAGE_SHIFT; + end_page = ((unsigned long)req->tc->pubuf + req->tc->pbuf_size + PAGE_SIZE - 1) >> PAGE_SHIFT; return end_page - start_page; } @@ -69,8 +69,8 @@ p9_payload_gup(struct p9_req_t *req, size_t *pdata_off, int *pdata_len, *pdata_off = (size_t)req->tc->pubuf & (PAGE_SIZE-1); if (*pdata_off) - first_page_bytes = min((PAGE_SIZE - *pdata_off), - req->tc->pbuf_size); + first_page_bytes = min(((size_t)PAGE_SIZE - *pdata_off), + req->tc->pbuf_size); rpinfo = req->tc->private; pdata_mapped_pages = get_user_pages_fast((unsigned long)req->tc->pubuf, diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c index a30471e..aa5672b 100644 --- a/net/9p/trans_fd.c +++ b/net/9p/trans_fd.c @@ -350,7 +350,7 @@ static void p9_read_work(struct work_struct *work) if (m->req->rc == NULL) { m->req->rc = kmalloc(sizeof(struct p9_fcall) + - m->client->msize, GFP_KERNEL); + m->client->msize, GFP_NOFS); if (!m->req->rc) { m->req = NULL; err = -ENOMEM; diff --git a/net/9p/trans_rdma.c b/net/9p/trans_rdma.c index 29a54cc..150e0c4 100644 --- a/net/9p/trans_rdma.c +++ b/net/9p/trans_rdma.c @@ -424,7 +424,7 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req) struct p9_rdma_context *rpl_context = NULL; /* Allocate an fcall for the reply */ - rpl_context = kmalloc(sizeof *rpl_context, GFP_KERNEL); + rpl_context = kmalloc(sizeof *rpl_context, GFP_NOFS); if (!rpl_context) { err = -ENOMEM; goto err_close; @@ -437,7 +437,7 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req) */ if (!req->rc) { req->rc = kmalloc(sizeof(struct p9_fcall)+client->msize, - GFP_KERNEL); + GFP_NOFS); if (req->rc) { req->rc->sdata = (char *) req->rc + sizeof(struct p9_fcall); @@ -468,7 +468,7 @@ static int rdma_request(struct p9_client *client, struct p9_req_t *req) req->rc = NULL; /* Post the request */ - c = kmalloc(sizeof *c, GFP_KERNEL); + c = kmalloc(sizeof *c, GFP_NOFS); if (!c) { err = -ENOMEM; goto err_free1; diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 9b550ed..e8f046b 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -43,6 +43,7 @@ #include <net/9p/client.h> #include <net/9p/transport.h> #include <linux/scatterlist.h> +#include <linux/swap.h> #include <linux/virtio.h> #include <linux/virtio_9p.h> #include "trans_common.h" @@ -51,6 +52,8 @@ /* a single mutex to manage channel initialization and attachment */ static DEFINE_MUTEX(virtio_9p_lock); +static DECLARE_WAIT_QUEUE_HEAD(vp_wq); +static atomic_t vp_pinned = ATOMIC_INIT(0); /** * struct virtio_chan - per-instance transport information @@ -78,7 +81,10 @@ struct virtio_chan { struct virtqueue *vq; int ring_bufs_avail; wait_queue_head_t *vc_wq; - + /* This is global limit. Since we don't have a global structure, + * will be placing it in each channel. + */ + int p9_max_pages; /* Scatterlist: can be too big for stack. */ struct scatterlist sg[VIRTQUEUE_NUM]; @@ -141,34 +147,36 @@ static void req_done(struct virtqueue *vq) P9_DPRINTK(P9_DEBUG_TRANS, ": request done\n"); - do { + while (1) { spin_lock_irqsave(&chan->lock, flags); rc = virtqueue_get_buf(chan->vq, &len); - if (rc != NULL) { - if (!chan->ring_bufs_avail) { - chan->ring_bufs_avail = 1; - wake_up(chan->vc_wq); - } - spin_unlock_irqrestore(&chan->lock, flags); - P9_DPRINTK(P9_DEBUG_TRANS, ": rc %p\n", rc); - P9_DPRINTK(P9_DEBUG_TRANS, ": lookup tag %d\n", - rc->tag); - req = p9_tag_lookup(chan->client, rc->tag); - req->status = REQ_STATUS_RCVD; - if (req->tc->private) { - struct trans_rpage_info *rp = req->tc->private; - /*Release pages */ - p9_release_req_pages(rp); - if (rp->rp_alloc) - kfree(rp); - req->tc->private = NULL; - } - p9_client_cb(chan->client, req); - } else { + if (rc == NULL) { spin_unlock_irqrestore(&chan->lock, flags); + break; + } + + chan->ring_bufs_avail = 1; + spin_unlock_irqrestore(&chan->lock, flags); + /* Wakeup if anyone waiting for VirtIO ring space. */ + wake_up(chan->vc_wq); + P9_DPRINTK(P9_DEBUG_TRANS, ": rc %p\n", rc); + P9_DPRINTK(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag); + req = p9_tag_lookup(chan->client, rc->tag); + if (req->tc->private) { + struct trans_rpage_info *rp = req->tc->private; + int p = rp->rp_nr_pages; + /*Release pages */ + p9_release_req_pages(rp); + atomic_sub(p, &vp_pinned); + wake_up(&vp_wq); + if (rp->rp_alloc) + kfree(rp); + req->tc->private = NULL; } - } while (rc != NULL); + req->status = REQ_STATUS_RCVD; + p9_client_cb(chan->client, req); + } } /** @@ -263,7 +271,6 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req) P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio request\n"); -req_retry: req->status = REQ_STATUS_SENT; if (req->tc->pbuf_size && (req->tc->pubuf && P9_IS_USER_CONTEXT)) { @@ -271,6 +278,14 @@ req_retry: int rpinfo_size = sizeof(struct trans_rpage_info) + sizeof(struct page *) * nr_pages; + if (atomic_read(&vp_pinned) >= chan->p9_max_pages) { + err = wait_event_interruptible(vp_wq, + atomic_read(&vp_pinned) < chan->p9_max_pages); + if (err == -ERESTARTSYS) + return err; + P9_DPRINTK(P9_DEBUG_TRANS, "9p: May gup pages now.\n"); + } + if (rpinfo_size <= (req->tc->capacity - req->tc->size)) { /* We can use sdata */ req->tc->private = req->tc->sdata + req->tc->size; @@ -293,9 +308,12 @@ req_retry: if (rpinfo->rp_alloc) kfree(rpinfo); return err; + } else { + atomic_add(rpinfo->rp_nr_pages, &vp_pinned); } } +req_retry_pinned: spin_lock_irqsave(&chan->lock, flags); /* Handle out VirtIO ring buffers */ @@ -356,7 +374,7 @@ req_retry: return err; P9_DPRINTK(P9_DEBUG_TRANS, "9p:Retry virtio request\n"); - goto req_retry; + goto req_retry_pinned; } else { spin_unlock_irqrestore(&chan->lock, flags); P9_DPRINTK(P9_DEBUG_TRANS, @@ -453,6 +471,8 @@ static int p9_virtio_probe(struct virtio_device *vdev) } init_waitqueue_head(chan->vc_wq); chan->ring_bufs_avail = 1; + /* Ceiling limit to avoid denial of service attacks */ + chan->p9_max_pages = nr_free_buffer_pages()/4; mutex_lock(&virtio_9p_lock); list_add_tail(&chan->chan_list, &virtio_chan_list); diff --git a/net/9p/util.c b/net/9p/util.c index e048701..b84619b 100644 --- a/net/9p/util.c +++ b/net/9p/util.c @@ -92,7 +92,7 @@ int p9_idpool_get(struct p9_idpool *p) unsigned long flags; retry: - if (idr_pre_get(&p->pool, GFP_KERNEL) == 0) + if (idr_pre_get(&p->pool, GFP_NOFS) == 0) return 0; spin_lock_irqsave(&p->lock, flags); |