| Message ID | 20221117222557.2196195-2-anirudh.venkataramanan@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Remove uses of kmap_atomic() | expand |
On giovedì 17 novembre 2022 23:25:53 CET Anirudh Venkataramanan wrote: > kmap_atomic() is being deprecated in favor of kmap_local_page(). > Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() > and kunmap_local() respectively. > > Note that kmap_atomic() disables preemption and page-fault processing, > but kmap_local_page() doesn't. Converting the former to the latter is safe > only if there isn't an implicit dependency on preemption and page-fault > handling being disabled, which does appear to be the case here. > > Also note that the page being mapped is not allocated by the driver, > and so the driver doesn't know if the page is in normal memory. This is the > reason kmap_local_page() is used as opposed to page_address(). > > I don't have hardware, so this change has only been compile tested. > > Cc: Ayush Sawal <ayush.sawal@chelsio.com> > Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> > Cc: Rohit Maheshwari <rohitm@chelsio.com> > Cc: Ira Weiny <ira.weiny@intel.com> > Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> > Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> > --- > .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c index > da9973b..d95f230 100644 > --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct > chcr_ktls_info *tx_info, i++; > } > f = &record->frags[i]; > - vaddr = kmap_atomic(skb_frag_page(f)); > + vaddr = kmap_local_page(skb_frag_page(f)); > > data = vaddr + skb_frag_off(f) + remaining; > frag_delta = skb_frag_size(f) - remaining; > > if (frag_delta >= prior_data_len) { > memcpy(prior_data, data, prior_data_len); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); > } else { > memcpy(prior_data, data, frag_delta); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); > /* get the next page */ > f = &record->frags[i + 1]; > - vaddr = kmap_atomic(skb_frag_page(f)); > + vaddr = kmap_local_page(skb_frag_page(f)); > data = vaddr + skb_frag_off(f); > memcpy(prior_data + frag_delta, > data, (prior_data_len - frag_delta)); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); > } > /* reset tcp_seq as per the prior_data_required len */ > tcp_seq -= prior_data_len; > -- > 2.37.2 The last conversion could have been done with memcpy_from_page(). However, it's not that a big deal. Therefore... Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Thanks, Fabio
On 11/18/2022 12:14 AM, Fabio M. De Francesco wrote: > On giovedì 17 novembre 2022 23:25:53 CET Anirudh Venkataramanan wrote: >> kmap_atomic() is being deprecated in favor of kmap_local_page(). >> Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() >> and kunmap_local() respectively. >> >> Note that kmap_atomic() disables preemption and page-fault processing, >> but kmap_local_page() doesn't. Converting the former to the latter is safe >> only if there isn't an implicit dependency on preemption and page-fault >> handling being disabled, which does appear to be the case here. >> >> Also note that the page being mapped is not allocated by the driver, >> and so the driver doesn't know if the page is in normal memory. This is the >> reason kmap_local_page() is used as opposed to page_address(). >> >> I don't have hardware, so this change has only been compile tested. >> >> Cc: Ayush Sawal <ayush.sawal@chelsio.com> >> Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> >> Cc: Rohit Maheshwari <rohitm@chelsio.com> >> Cc: Ira Weiny <ira.weiny@intel.com> >> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> >> Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> >> --- >> .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- >> 1 file changed, 5 insertions(+), 5 deletions(-) >> >> diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c >> b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c index >> da9973b..d95f230 100644 >> --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c >> +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c >> @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct >> chcr_ktls_info *tx_info, i++; >> } >> f = &record->frags[i]; >> - vaddr = kmap_atomic(skb_frag_page(f)); >> + vaddr = kmap_local_page(skb_frag_page(f)); >> >> data = vaddr + skb_frag_off(f) + remaining; >> frag_delta = skb_frag_size(f) - remaining; >> >> if (frag_delta >= prior_data_len) { >> memcpy(prior_data, data, > prior_data_len); >> - kunmap_atomic(vaddr); >> + kunmap_local(vaddr); >> } else { >> memcpy(prior_data, data, frag_delta); >> - kunmap_atomic(vaddr); >> + kunmap_local(vaddr); >> /* get the next page */ >> f = &record->frags[i + 1]; >> - vaddr = kmap_atomic(skb_frag_page(f)); >> + vaddr = > kmap_local_page(skb_frag_page(f)); >> data = vaddr + skb_frag_off(f); >> memcpy(prior_data + frag_delta, >> data, (prior_data_len - > frag_delta)); >> - kunmap_atomic(vaddr); >> + kunmap_local(vaddr); >> } >> /* reset tcp_seq as per the prior_data_required > len */ >> tcp_seq -= prior_data_len; >> -- >> 2.37.2 > > The last conversion could have been done with memcpy_from_page(). However, > it's not that a big deal. Therefore... > > Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> Yeah, using memcpy_from_page() is cleaner. I'll update this patch, and probably 4/5 too. Thanks! Ani
On venerdì 18 novembre 2022 19:27:56 CET Anirudh Venkataramanan wrote: > On 11/18/2022 12:14 AM, Fabio M. De Francesco wrote: > > On giovedì 17 novembre 2022 23:25:53 CET Anirudh Venkataramanan wrote: > >> kmap_atomic() is being deprecated in favor of kmap_local_page(). > >> Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() > >> and kunmap_local() respectively. > >> > >> Note that kmap_atomic() disables preemption and page-fault processing, > >> but kmap_local_page() doesn't. Converting the former to the latter is safe > >> only if there isn't an implicit dependency on preemption and page-fault > >> handling being disabled, which does appear to be the case here. > >> > >> Also note that the page being mapped is not allocated by the driver, > >> and so the driver doesn't know if the page is in normal memory. This is the > >> reason kmap_local_page() is used as opposed to page_address(). > >> > >> I don't have hardware, so this change has only been compile tested. > >> > >> Cc: Ayush Sawal <ayush.sawal@chelsio.com> > >> Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> > >> Cc: Rohit Maheshwari <rohitm@chelsio.com> > >> Cc: Ira Weiny <ira.weiny@intel.com> > >> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> > >> Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> > >> --- > >> > >> .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- > >> 1 file changed, 5 insertions(+), 5 deletions(-) > >> > >> diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/ chcr_ktls.c > >> b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c index > >> da9973b..d95f230 100644 > >> --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > >> +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > >> @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct > >> chcr_ktls_info *tx_info, i++; > >> > >> } > >> f = &record->frags[i]; > >> > >> - vaddr = kmap_atomic(skb_frag_page(f)); > >> + vaddr = kmap_local_page(skb_frag_page(f)); > >> > >> data = vaddr + skb_frag_off(f) + remaining; > >> frag_delta = skb_frag_size(f) - remaining; > >> > >> if (frag_delta >= prior_data_len) { > >> > >> memcpy(prior_data, data, > > > > prior_data_len); > > > >> - kunmap_atomic(vaddr); > >> + kunmap_local(vaddr); > >> > >> } else { > >> > >> memcpy(prior_data, data, frag_delta); > >> > >> - kunmap_atomic(vaddr); > >> + kunmap_local(vaddr); > >> > >> /* get the next page */ > >> f = &record->frags[i + 1]; > >> > >> - vaddr = kmap_atomic(skb_frag_page(f)); > >> + vaddr = > > > > kmap_local_page(skb_frag_page(f)); > > > >> data = vaddr + skb_frag_off(f); > >> memcpy(prior_data + frag_delta, > >> > >> data, (prior_data_len - > > > > frag_delta)); > > > >> - kunmap_atomic(vaddr); > >> + kunmap_local(vaddr); > >> > >> } > >> /* reset tcp_seq as per the prior_data_required > > > > len */ > > > >> tcp_seq -= prior_data_len; > >> > >> -- > >> 2.37.2 > > > > The last conversion could have been done with memcpy_from_page(). However, > > it's not that a big deal. Therefore... > > > > Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> > > Yeah, using memcpy_from_page() is cleaner. I'll update this patch, and > probably 4/5 too. > > Thanks! > Ani Well, I didn't ask you for a second version. This is why you already see my "Reviewed-by:" tag. I'm OK with your changes. I just warned you that maintainers might ask, so I'd wait and see. However it's up to you. However, if you decide to send this patch with memcpy_from_page(), why you are not sure about 4/5? Since you decided to send 1/5 again, what does prevent you from updating also 4/5? Fabio
On 11/18/2022 12:18 PM, Fabio M. De Francesco wrote: > On venerdì 18 novembre 2022 19:27:56 CET Anirudh Venkataramanan wrote: >> On 11/18/2022 12:14 AM, Fabio M. De Francesco wrote: >>> On giovedì 17 novembre 2022 23:25:53 CET Anirudh Venkataramanan wrote: >>>> kmap_atomic() is being deprecated in favor of kmap_local_page(). >>>> Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() >>>> and kunmap_local() respectively. >>>> >>>> Note that kmap_atomic() disables preemption and page-fault processing, >>>> but kmap_local_page() doesn't. Converting the former to the latter is > safe >>>> only if there isn't an implicit dependency on preemption and page-fault >>>> handling being disabled, which does appear to be the case here. >>>> >>>> Also note that the page being mapped is not allocated by the driver, >>>> and so the driver doesn't know if the page is in normal memory. This is > the >>>> reason kmap_local_page() is used as opposed to page_address(). >>>> >>>> I don't have hardware, so this change has only been compile tested. >>>> >>>> Cc: Ayush Sawal <ayush.sawal@chelsio.com> >>>> Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> >>>> Cc: Rohit Maheshwari <rohitm@chelsio.com> >>>> Cc: Ira Weiny <ira.weiny@intel.com> >>>> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> >>>> Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> >>>> --- >>>> >>>> .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- >>>> 1 file changed, 5 insertions(+), 5 deletions(-) >>>> >>>> diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/ > chcr_ktls.c >>>> b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c index >>>> da9973b..d95f230 100644 >>>> --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c >>>> +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c >>>> @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct >>>> chcr_ktls_info *tx_info, i++; >>>> >>>> } >>>> f = &record->frags[i]; >>>> >>>> - vaddr = kmap_atomic(skb_frag_page(f)); >>>> + vaddr = kmap_local_page(skb_frag_page(f)); >>>> >>>> data = vaddr + skb_frag_off(f) + remaining; >>>> frag_delta = skb_frag_size(f) - remaining; >>>> >>>> if (frag_delta >= prior_data_len) { >>>> >>>> memcpy(prior_data, data, >>> >>> prior_data_len); >>> >>>> - kunmap_atomic(vaddr); >>>> + kunmap_local(vaddr); >>>> >>>> } else { >>>> >>>> memcpy(prior_data, data, frag_delta); >>>> >>>> - kunmap_atomic(vaddr); >>>> + kunmap_local(vaddr); >>>> >>>> /* get the next page */ >>>> f = &record->frags[i + 1]; >>>> >>>> - vaddr = kmap_atomic(skb_frag_page(f)); >>>> + vaddr = >>> >>> kmap_local_page(skb_frag_page(f)); >>> >>>> data = vaddr + skb_frag_off(f); >>>> memcpy(prior_data + frag_delta, >>>> >>>> data, (prior_data_len - >>> >>> frag_delta)); >>> >>>> - kunmap_atomic(vaddr); >>>> + kunmap_local(vaddr); >>>> >>>> } >>>> /* reset tcp_seq as per the prior_data_required >>> >>> len */ >>> >>>> tcp_seq -= prior_data_len; >>>> >>>> -- >>>> 2.37.2 >>> >>> The last conversion could have been done with memcpy_from_page(). However, >>> it's not that a big deal. Therefore... >>> >>> Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com> >> >> Yeah, using memcpy_from_page() is cleaner. I'll update this patch, and >> probably 4/5 too. >> >> Thanks! >> Ani > > Well, I didn't ask you for a second version. This is why you already see my > "Reviewed-by:" tag. I'm OK with your changes. I just warned you that > maintainers might ask, so I'd wait and see. However it's up to you. I understand and appreciate your "Reviewed-by", but that doesn't mean further improvements aren't possible. I believe using memcpy_from_page() is better, and plan to do this in v2. > > However, if you decide to send this patch with memcpy_from_page(), why you > are not sure about 4/5? Since you decided to send 1/5 again, what does prevent > you from updating also 4/5? I hadn't seen patch 4/5 when I replied to you. Since then I have, and so I'll be updating 4/5 to use memcpy_from_page() as well. Ani
On Thu, Nov 17, 2022 at 02:25:53PM -0800, Venkataramanan, Anirudh wrote: > kmap_atomic() is being deprecated in favor of kmap_local_page(). > Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() > and kunmap_local() respectively. > > Note that kmap_atomic() disables preemption and page-fault processing, > but kmap_local_page() doesn't. Converting the former to the latter is safe > only if there isn't an implicit dependency on preemption and page-fault > handling being disabled, which does appear to be the case here. does not? Also, say 'is not the case here'. Appearances are not enough. But we know that this code is safe doing only memcpy's. > > Also note that the page being mapped is not allocated by the driver, > and so the driver doesn't know if the page is in normal memory. This is the > reason kmap_local_page() is used as opposed to page_address(). > > I don't have hardware, so this change has only been compile tested. > > Cc: Ayush Sawal <ayush.sawal@chelsio.com> > Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> > Cc: Rohit Maheshwari <rohitm@chelsio.com> > Cc: Ira Weiny <ira.weiny@intel.com> > Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> > Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> > --- > .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > index da9973b..d95f230 100644 > --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c > @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct chcr_ktls_info *tx_info, > i++; > } > f = &record->frags[i]; > - vaddr = kmap_atomic(skb_frag_page(f)); > + vaddr = kmap_local_page(skb_frag_page(f)); > > data = vaddr + skb_frag_off(f) + remaining; > frag_delta = skb_frag_size(f) - remaining; > > if (frag_delta >= prior_data_len) { > memcpy(prior_data, data, prior_data_len); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); > } else { > memcpy(prior_data, data, frag_delta); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); > /* get the next page */ > f = &record->frags[i + 1]; > - vaddr = kmap_atomic(skb_frag_page(f)); > + vaddr = kmap_local_page(skb_frag_page(f)); > data = vaddr + skb_frag_off(f); > memcpy(prior_data + frag_delta, > data, (prior_data_len - frag_delta)); > - kunmap_atomic(vaddr); > + kunmap_local(vaddr); Agree with Fabio that this needs to be memcpy_from_page(). We should be consistent in using it. Ira > } > /* reset tcp_seq as per the prior_data_required len */ > tcp_seq -= prior_data_len; > -- > 2.37.2 >
diff --git a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c index da9973b..d95f230 100644 --- a/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c +++ b/drivers/net/ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c @@ -1853,24 +1853,24 @@ static int chcr_short_record_handler(struct chcr_ktls_info *tx_info, i++; } f = &record->frags[i]; - vaddr = kmap_atomic(skb_frag_page(f)); + vaddr = kmap_local_page(skb_frag_page(f)); data = vaddr + skb_frag_off(f) + remaining; frag_delta = skb_frag_size(f) - remaining; if (frag_delta >= prior_data_len) { memcpy(prior_data, data, prior_data_len); - kunmap_atomic(vaddr); + kunmap_local(vaddr); } else { memcpy(prior_data, data, frag_delta); - kunmap_atomic(vaddr); + kunmap_local(vaddr); /* get the next page */ f = &record->frags[i + 1]; - vaddr = kmap_atomic(skb_frag_page(f)); + vaddr = kmap_local_page(skb_frag_page(f)); data = vaddr + skb_frag_off(f); memcpy(prior_data + frag_delta, data, (prior_data_len - frag_delta)); - kunmap_atomic(vaddr); + kunmap_local(vaddr); } /* reset tcp_seq as per the prior_data_required len */ tcp_seq -= prior_data_len;
kmap_atomic() is being deprecated in favor of kmap_local_page(). Replace kmap_atomic() and kunmap_atomic() with kmap_local_page() and kunmap_local() respectively. Note that kmap_atomic() disables preemption and page-fault processing, but kmap_local_page() doesn't. Converting the former to the latter is safe only if there isn't an implicit dependency on preemption and page-fault handling being disabled, which does appear to be the case here. Also note that the page being mapped is not allocated by the driver, and so the driver doesn't know if the page is in normal memory. This is the reason kmap_local_page() is used as opposed to page_address(). I don't have hardware, so this change has only been compile tested. Cc: Ayush Sawal <ayush.sawal@chelsio.com> Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com> Cc: Rohit Maheshwari <rohitm@chelsio.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com> Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com> --- .../ethernet/chelsio/inline_crypto/ch_ktls/chcr_ktls.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)