From 8db0edc4acb1c654e4c115a3978fb2681c5bfb74 Mon Sep 17 00:00:00 2001 From: Michael Kelley Date: Thu, 11 Jan 2024 08:54:50 -0800 Subject: Drivers: hv: vmbus: Remove duplication and cleanup code in create_gpadl_header() create_gpadl_header() creates a message header, and one or more message bodies if the number of GPADL entries exceeds what fits in the header. Currently the code for creating the message header is duplicated in the two halves of the main "if" statement governing whether message bodies are created. Eliminate the duplication by making minor tweaks to the logic and associated comments. While here, simplify the handling of memory allocation errors, and use umin() instead of open coding it. For ease of review, the indentation of sizable chunks of code is *not* changed. A follow-on patch updates only the indentation. No functional change. Suggested-by: Dan Carpenter Signed-off-by: Michael Kelley Link: https://lore.kernel.org/r/20240111165451.269418-1-mhklinux@outlook.com Signed-off-by: Wei Liu Message-ID: <20240111165451.269418-1-mhklinux@outlook.com> --- drivers/hv/channel.c | 54 ++++++++++------------------------------------------ 1 file changed, 10 insertions(+), 44 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 56f7e06c673e..604f5aff8502 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -322,21 +322,17 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer, pagecount = hv_gpadl_size(type, size) >> HV_HYP_PAGE_SHIFT; - /* do we need a gpadl body msg */ pfnsize = MAX_SIZE_CHANNEL_MESSAGE - sizeof(struct vmbus_channel_gpadl_header) - sizeof(struct gpa_range); - pfncount = pfnsize / sizeof(u64); + pfncount = umin(pagecount, pfnsize / sizeof(u64)); - if (pagecount > pfncount) { - /* we need a gpadl body */ - /* fill in the header */ msgsize = sizeof(struct vmbus_channel_msginfo) + sizeof(struct vmbus_channel_gpadl_header) + sizeof(struct gpa_range) + pfncount * sizeof(u64); msgheader = kzalloc(msgsize, GFP_KERNEL); if (!msgheader) - goto nomem; + return -ENOMEM; INIT_LIST_HEAD(&msgheader->submsglist); msgheader->msgsize = msgsize; @@ -356,18 +352,17 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer, pfnsum = pfncount; pfnleft = pagecount - pfncount; - /* how many pfns can we fit */ + /* how many pfns can we fit in a body message */ pfnsize = MAX_SIZE_CHANNEL_MESSAGE - sizeof(struct vmbus_channel_gpadl_body); pfncount = pfnsize / sizeof(u64); - /* fill in the body */ + /* + * If pfnleft is zero, everything fits in the header and no body + * messages are needed + */ while (pfnleft) { - if (pfnleft > pfncount) - pfncurr = pfncount; - else - pfncurr = pfnleft; - + pfncurr = umin(pfncount, pfnleft); msgsize = sizeof(struct vmbus_channel_msginfo) + sizeof(struct vmbus_channel_gpadl_body) + pfncurr * sizeof(u64); @@ -386,8 +381,8 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer, list_del(&pos->msglistentry); kfree(pos); } - - goto nomem; + kfree(msgheader); + return -ENOMEM; } msgbody->msgsize = msgsize; @@ -410,37 +405,8 @@ static int create_gpadl_header(enum hv_gpadl_type type, void *kbuffer, pfnsum += pfncurr; pfnleft -= pfncurr; } - } else { - /* everything fits in a header */ - msgsize = sizeof(struct vmbus_channel_msginfo) + - sizeof(struct vmbus_channel_gpadl_header) + - sizeof(struct gpa_range) + pagecount * sizeof(u64); - msgheader = kzalloc(msgsize, GFP_KERNEL); - if (msgheader == NULL) - goto nomem; - - INIT_LIST_HEAD(&msgheader->submsglist); - msgheader->msgsize = msgsize; - - gpadl_header = (struct vmbus_channel_gpadl_header *) - msgheader->msg; - gpadl_header->rangecount = 1; - gpadl_header->range_buflen = sizeof(struct gpa_range) + - pagecount * sizeof(u64); - gpadl_header->range[0].byte_offset = 0; - gpadl_header->range[0].byte_count = hv_gpadl_size(type, size); - for (i = 0; i < pagecount; i++) - gpadl_header->range[0].pfn_array[i] = hv_gpadl_hvpfn( - type, kbuffer, size, send_offset, i); - - *msginfo = msgheader; - } return 0; -nomem: - kfree(msgheader); - kfree(msgbody); - return -ENOMEM; } /* -- cgit v1.2.3