From 98f531b10d23e3c28e8d34c0e88822a81231b3c2 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Fri, 2 Sep 2016 05:58:19 -0700 Subject: [PATCH] Drivers: hv: cleanup vmbus_open() for wrap around mappings In preparation for doing wrap around mappings for ring buffers cleanup vmbus_open() function: - check that ring sizes are PAGE_SIZE aligned (they are for all in-kernel drivers now); - kfree(open_info) on error only after we kzalloc() it (not an issue as it is valid to call kfree(NULL); - rename poorly named labels; - use alloc_pages() instead of __get_free_pages() as we need struct page pointer for future. Signed-off-by: Vitaly Kuznetsov Tested-by: Dexuan Cui Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- drivers/hv/channel.c | 41 ++++++++++++++++++++++------------------- 1 file changed, 22 insertions(+), 19 deletions(-) diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 884cebf5f9b9..15e833004fc3 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -80,6 +80,10 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, int ret, err = 0; struct page *page; + if (send_ringbuffer_size % PAGE_SIZE || + recv_ringbuffer_size % PAGE_SIZE) + return -EINVAL; + spin_lock_irqsave(&newchannel->lock, flags); if (newchannel->state == CHANNEL_OPEN_STATE) { newchannel->state = CHANNEL_OPENING_STATE; @@ -99,17 +103,16 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, recv_ringbuffer_size)); if (!page) - out = (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, - get_order(send_ringbuffer_size + - recv_ringbuffer_size)); - else - out = (void *)page_address(page); + page = alloc_pages(GFP_KERNEL|__GFP_ZERO, + get_order(send_ringbuffer_size + + recv_ringbuffer_size)); - if (!out) { + if (!page) { err = -ENOMEM; - goto error0; + goto error_set_chnstate; } + out = page_address(page); in = (void *)((unsigned long)out + send_ringbuffer_size); newchannel->ringbuffer_pages = out; @@ -121,14 +124,14 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, if (ret != 0) { err = ret; - goto error0; + goto error_free_pages; } ret = hv_ringbuffer_init( &newchannel->inbound, in, recv_ringbuffer_size); if (ret != 0) { err = ret; - goto error0; + goto error_free_pages; } @@ -143,7 +146,7 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, if (ret != 0) { err = ret; - goto error0; + goto error_free_pages; } /* Create and init the channel open message */ @@ -152,7 +155,7 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, GFP_KERNEL); if (!open_info) { err = -ENOMEM; - goto error_gpadl; + goto error_free_gpadl; } init_completion(&open_info->waitevent); @@ -168,7 +171,7 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, if (userdatalen > MAX_USER_DEFINED_BYTES) { err = -EINVAL; - goto error_gpadl; + goto error_free_gpadl; } if (userdatalen) @@ -184,7 +187,7 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, if (ret != 0) { err = ret; - goto error1; + goto error_clean_msglist; } wait_for_completion(&open_info->waitevent); @@ -195,25 +198,25 @@ int vmbus_open(struct vmbus_channel *newchannel, u32 send_ringbuffer_size, if (open_info->response.open_result.status) { err = -EAGAIN; - goto error_gpadl; + goto error_free_gpadl; } newchannel->state = CHANNEL_OPENED_STATE; kfree(open_info); return 0; -error1: +error_clean_msglist: spin_lock_irqsave(&vmbus_connection.channelmsg_lock, flags); list_del(&open_info->msglistentry); spin_unlock_irqrestore(&vmbus_connection.channelmsg_lock, flags); -error_gpadl: +error_free_gpadl: vmbus_teardown_gpadl(newchannel, newchannel->ringbuffer_gpadlhandle); - -error0: + kfree(open_info); +error_free_pages: free_pages((unsigned long)out, get_order(send_ringbuffer_size + recv_ringbuffer_size)); - kfree(open_info); +error_set_chnstate: newchannel->state = CHANNEL_OPEN_STATE; return err; } -- 2.20.1